成都网站关键词优化,菜鸟教程网站怎么做,北京市网站建设公司排名,python文章发布wordpress1.传入日期跨度#xff0c;选择上架日期时#xff0c;自动显示下架日期 2.手动选择上架日期和下架日期(图中下架日期自动填了只需CalendarDateRangePicker在initState方法中使用_startDate widget.initialStartDate; _endDate widget.initialEndDate;#xff0c;而不直接…1.传入日期跨度选择上架日期时自动显示下架日期 2.手动选择上架日期和下架日期(图中下架日期自动填了只需CalendarDateRangePicker在initState方法中使用_startDate widget.initialStartDate; _endDate widget.initialEndDate;而不直接引用widget.initialStartDate、widget.initialEndDate;利用initState方法只在初始化时调用一次的特性) 从flutter源码中找到一个组件showDateRangePicker它的效果是这样的主体功能一样只是有些不同。要通过它来实现上图中的功能只能进行微改。 先把需要的的日历部分功能从源码中抽出来是flutter2.10.5的环境所以抽出来以后改了一点点late、?、的语法差异
import package:jade/customWidget/JadeDateRange/FocusedDate.dart;
import package:flutter/material.dart;
import package:flutter/services.dart;class CalendarKeyboardNavigator extends StatefulWidget {const CalendarKeyboardNavigator({Key key,this.child,this.firstDate,this.lastDate,this.initialFocusedDay,}) : super(key: key);final Widget child;final DateTime firstDate;final DateTime lastDate;final DateTime initialFocusedDay;override_CalendarKeyboardNavigatorState createState() _CalendarKeyboardNavigatorState();
}class _CalendarKeyboardNavigatorState extends StateCalendarKeyboardNavigator {final MapShortcutActivator, Intent _shortcutMap const ShortcutActivator, Intent{SingleActivator(LogicalKeyboardKey.arrowLeft): DirectionalFocusIntent(TraversalDirection.left),SingleActivator(LogicalKeyboardKey.arrowRight): DirectionalFocusIntent(TraversalDirection.right),SingleActivator(LogicalKeyboardKey.arrowDown): DirectionalFocusIntent(TraversalDirection.down),SingleActivator(LogicalKeyboardKey.arrowUp): DirectionalFocusIntent(TraversalDirection.up),};MapType, ActionIntent _actionMap;FocusNode _dayGridFocus;TraversalDirection _dayTraversalDirection;DateTime _focusedDay;overridevoid initState() {super.initState();_actionMap Type, ActionIntent{NextFocusIntent: CallbackActionNextFocusIntent(onInvoke: _handleGridNextFocus),PreviousFocusIntent: CallbackActionPreviousFocusIntent(onInvoke: _handleGridPreviousFocus),DirectionalFocusIntent: CallbackActionDirectionalFocusIntent(onInvoke: _handleDirectionFocus),};_dayGridFocus FocusNode(debugLabel: Day Grid);}overridevoid dispose() {_dayGridFocus.dispose();super.dispose();}void _handleGridFocusChange(bool focused) {setState(() {if (focused) {_focusedDay ?? widget.initialFocusedDay;}});}/// Move focus to the next element after the day grid.void _handleGridNextFocus(NextFocusIntent intent) {_dayGridFocus.requestFocus();_dayGridFocus.nextFocus();}/// Move focus to the previous element before the day grid.void _handleGridPreviousFocus(PreviousFocusIntent intent) {_dayGridFocus.requestFocus();_dayGridFocus.previousFocus();}/// Move the internal focus date in the direction of the given intent.////// This will attempt to move the focused day to the next selectable day in/// the given direction. If the new date is not in the current month, then/// the page view will be scrolled to show the new dates month.////// For horizontal directions, it will move forward or backward a day (depending/// on the current [TextDirection]). For vertical directions it will move up and/// down a week at a time.void _handleDirectionFocus(DirectionalFocusIntent intent) {assert(_focusedDay ! null);setState(() {final DateTime nextDate _nextDateInDirection(_focusedDay, intent.direction);if (nextDate ! null) {_focusedDay nextDate;_dayTraversalDirection intent.direction;}});}static const MapTraversalDirection, int _directionOffset TraversalDirection, int{TraversalDirection.up: -DateTime.daysPerWeek,TraversalDirection.right: 1,TraversalDirection.down: DateTime.daysPerWeek,TraversalDirection.left: -1,};int _dayDirectionOffset(TraversalDirection traversalDirection, TextDirection textDirection) {// Swap left and right if the text direction if RTLif (textDirection TextDirection.rtl) {if (traversalDirection TraversalDirection.left)traversalDirection TraversalDirection.right;else if (traversalDirection TraversalDirection.right)traversalDirection TraversalDirection.left;}return _directionOffset[traversalDirection];}DateTime _nextDateInDirection(DateTime date, TraversalDirection direction) {final TextDirection textDirection Directionality.of(context);final DateTime nextDate DateUtils.addDaysToDate(date, _dayDirectionOffset(direction, textDirection));if (!nextDate.isBefore(widget.firstDate) !nextDate.isAfter(widget.lastDate)) {return nextDate;}return null;}overrideWidget build(BuildContext context) {return FocusableActionDetector(shortcuts: _shortcutMap,actions: _actionMap,focusNode: _dayGridFocus,onFocusChange: _handleGridFocusChange,child: FocusedDate(date: _dayGridFocus.hasFocus ? _focusedDay : null,scrollDirection: _dayGridFocus.hasFocus ? _dayTraversalDirection : null,child: widget.child,),);}
}import package:jade/customWidget/JadeDateRange/MonthItemGridDelegate.dart;
import package:flutter/material.dart;class DayHeaders extends StatelessWidget {/// Builds widgets showing abbreviated days of week. The first widget in the/// returned list corresponds to the first day of week for the current locale.////// Examples:////// /// ┌ Sunday is the first day of week in the US (en_US)/// |/// S M T W T F S -- the returned list contains these widgets/// _ _ _ _ _ 1 2/// 3 4 5 6 7 8 9////// ┌ But its Monday in the UK (en_GB)/// |/// M T W T F S S -- the returned list contains these widgets/// _ _ _ _ 1 2 3/// 4 5 6 7 8 9 10/// ListWidget _getDayHeaders(TextStyle headerStyle, MaterialLocalizations localizations) {final ListWidget result Widget[];for (int i localizations.firstDayOfWeekIndex; true; i (i 1) % 7) {final String weekday localizations.narrowWeekdays[i];result.add(ExcludeSemantics(child: Center(child: Text(weekday, style: headerStyle)),));if (i (localizations.firstDayOfWeekIndex - 1) % 7)break;}return result;}overrideWidget build(BuildContext context) {final ThemeData themeData Theme.of(context);final ColorScheme colorScheme themeData.colorScheme;final TextStyle textStyle themeData.textTheme.subtitle2.apply(color: colorScheme.onSurface);final MaterialLocalizations localizations MaterialLocalizations.of(context);final ListWidget labels _getDayHeaders(textStyle, localizations);// Add leading and trailing containers for edges of the custom grid layout.labels.insert(0, Container());labels.add(Container());return Container(constraints: BoxConstraints(maxWidth: MediaQuery.of(context).orientation Orientation.landscape? 384.0: 480.0,maxHeight: 42.0,),child: GridView.custom(shrinkWrap: true,gridDelegate: const MonthItemGridDelegate(),childrenDelegate: SliverChildListDelegate(labels,addRepaintBoundaries: false,),),);}
}import package:flutter/material.dart;class FocusedDate extends InheritedWidget {const FocusedDate({Key key,Widget child,this.date,this.scrollDirection,}) : super(key: key, child: child);final DateTime date;final TraversalDirection scrollDirection;overridebool updateShouldNotify(FocusedDate oldWidget) {return !DateUtils.isSameDay(date, oldWidget.date) || scrollDirection ! oldWidget.scrollDirection;}static FocusedDate of(BuildContext context) {return context.dependOnInheritedWidgetOfExactTypeFocusedDate();}
}import package:flutter/material.dart;enum HighlightPainterStyle {/// Paints nothing.none,/// Paints a rectangle that occupies the leading half of the space.highlightLeading,/// Paints a rectangle that occupies the trailing half of the space.highlightTrailing,/// Paints a rectangle that occupies all available space.highlightAll,
}class HighlightPainter extends CustomPainter {HighlightPainter({this.color,this.style HighlightPainterStyle.none,this.textDirection,});final Color color;final HighlightPainterStyle style;final TextDirection textDirection;overridevoid paint(Canvas canvas, Size size) {if (style HighlightPainterStyle.none) {return;}final Paint paint Paint()..color color..style PaintingStyle.fill;final Rect rectLeft Rect.fromLTWH(0, 0, size.width / 2, size.height);final Rect rectRight Rect.fromLTWH(size.width / 2, 0, size.width / 2, size.height);switch (style) {case HighlightPainterStyle.highlightTrailing:canvas.drawRect(textDirection TextDirection.ltr ? rectRight : rectLeft,paint,);break;case HighlightPainterStyle.highlightLeading:canvas.drawRect(textDirection TextDirection.ltr ? rectLeft : rectRight,paint,);break;case HighlightPainterStyle.highlightAll:canvas.drawRect(Rect.fromLTWH(0, 0, size.width, size.height),paint,);break;case HighlightPainterStyle.none:break;}}overridebool shouldRepaint(CustomPainter oldDelegate) false;
}import package:jade/customWidget/JadeDateRange/FocusedDate.dart;
import package:jade/customWidget/JadeDateRange/HighlightPainter.dart;
import package:jade/customWidget/JadeDateRange/MonthItemGridDelegate.dart;
import package:jade/utils/JadeColors.dart;
import package:flutter/gestures.dart;
import package:flutter/material.dart;
import dart:math as math;const Duration _monthScrollDuration Duration(milliseconds: 200);
const double _monthItemHeaderHeight 58.0;
const double _monthItemFooterHeight 12.0;
const double _monthItemRowHeight 42.0;
const double _monthItemSpaceBetweenRows 8.0;
const double _maxCalendarWidthLandscape 384.0;
const double _maxCalendarWidthPortrait 480.0;class MonthItem extends StatefulWidget {/// Creates a month item.MonthItem({Key key,this.selectedDateStart,this.selectedDateEnd,this.currentDate,this.onChanged,this.firstDate,this.lastDate,this.displayedMonth,this.blackoutDateTimes,this.isAllDisabled,this.dragStartBehavior DragStartBehavior.start,}) : assert(firstDate ! null),assert(lastDate ! null),assert(!firstDate.isAfter(lastDate)),assert(selectedDateStart null || !selectedDateStart.isBefore(firstDate)),assert(selectedDateEnd null || !selectedDateEnd.isBefore(firstDate)),assert(selectedDateStart null || !selectedDateStart.isAfter(lastDate)),assert(selectedDateEnd null || !selectedDateEnd.isAfter(lastDate)),assert(selectedDateStart null || selectedDateEnd null || !selectedDateStart.isAfter(selectedDateEnd)),assert(currentDate ! null),assert(onChanged ! null),assert(displayedMonth ! null),assert(dragStartBehavior ! null),super(key: key);/// The currently selected start date.////// This date is highlighted in the picker.final DateTime selectedDateStart;/// The currently selected end date.////// This date is highlighted in the picker.final DateTime selectedDateEnd;/// The current date at the time the picker is displayed.final DateTime currentDate;/// Called when the user picks a day.final ValueChangedDateTime onChanged;/// The earliest date the user is permitted to pick.final DateTime firstDate;/// The latest date the user is permitted to pick.final DateTime lastDate;/// The month whose days are displayed by this picker.final DateTime displayedMonth;//传入的设置失效的日期置灰、禁用不可点击final ListDateTime blackoutDateTimes;///日期是否可以点击final bool isAllDisabled;/// Determines the way that drag start behavior is handled.////// If set to [DragStartBehavior.start], the drag gesture used to scroll a/// date picker wheel will begin at the position where the drag gesture won/// the arena. If set to [DragStartBehavior.down] it will begin at the position/// where a down event is first detected.////// In general, setting this to [DragStartBehavior.start] will make drag/// animation smoother and setting it to [DragStartBehavior.down] will make/// drag behavior feel slightly more reactive.////// By default, the drag start behavior is [DragStartBehavior.start].////// See also:////// * [DragGestureRecognizer.dragStartBehavior], which gives an example for/// the different behaviors.final DragStartBehavior dragStartBehavior;override_MonthItemState createState() _MonthItemState();
}class _MonthItemState extends StateMonthItem {/// List of [FocusNode]s, one for each day of the month.ListFocusNode _dayFocusNodes;overridevoid initState() {super.initState();final int daysInMonth DateUtils.getDaysInMonth(widget.displayedMonth.year, widget.displayedMonth.month);_dayFocusNodes ListFocusNode.generate(daysInMonth,(int index) FocusNode(skipTraversal: true, debugLabel: Day ${index 1}),);}overridevoid didChangeDependencies() {super.didChangeDependencies();// Check to see if the focused date is in this month, if so focus it.final DateTime focusedDate FocusedDate.of(context)?.date;if (focusedDate ! null DateUtils.isSameMonth(widget.displayedMonth, focusedDate)) {_dayFocusNodes[focusedDate.day - 1].requestFocus();}}overridevoid dispose() {for (final FocusNode node in _dayFocusNodes) {node.dispose();}super.dispose();}Color _highlightColor(BuildContext context) {return Theme.of(context).colorScheme.primary.withOpacity(0.12);}void _dayFocusChanged(bool focused) {if (focused) {final TraversalDirection focusDirection FocusedDate.of(context)?.scrollDirection;if (focusDirection ! null) {ScrollPositionAlignmentPolicy policy ScrollPositionAlignmentPolicy.explicit;switch (focusDirection) {case TraversalDirection.up:case TraversalDirection.left:policy ScrollPositionAlignmentPolicy.keepVisibleAtStart;break;case TraversalDirection.right:case TraversalDirection.down:policy ScrollPositionAlignmentPolicy.keepVisibleAtEnd;break;}Scrollable.ensureVisible(primaryFocus.context,duration: _monthScrollDuration,alignmentPolicy: policy,);}}}Widget _buildDayItem(BuildContext context, DateTime dayToBuild, int firstDayOffset, int daysInMonth) {final ThemeData theme Theme.of(context);final ColorScheme colorScheme theme.colorScheme;final TextTheme textTheme theme.textTheme;final MaterialLocalizations localizations MaterialLocalizations.of(context);final TextDirection textDirection Directionality.of(context);final Color highlightColor _highlightColor(context);final int day dayToBuild.day;final bool isDisabled dayToBuild.isAfter(widget.lastDate) || dayToBuild.isBefore(widget.firstDate) || widget.blackoutDateTimes.contains(dayToBuild) || widget.isAllDisabled;BoxDecoration decoration;TextStyle itemStyle textTheme.bodyText2;final bool isRangeSelected widget.selectedDateStart ! null widget.selectedDateEnd ! null;final bool isSelectedDayStart widget.selectedDateStart ! null dayToBuild.isAtSameMomentAs(widget.selectedDateStart);final bool isSelectedDayEnd widget.selectedDateEnd ! null dayToBuild.isAtSameMomentAs(widget.selectedDateEnd);final bool isInRange isRangeSelected dayToBuild.isAfter(widget.selectedDateStart) dayToBuild.isBefore(widget.selectedDateEnd);HighlightPainter highlightPainter;if (isSelectedDayStart || isSelectedDayEnd) {// The selected start and end dates gets a circle background// highlight, and a contrasting text color.itemStyle textTheme.bodyText2?.apply(color: colorScheme.onPrimary);decoration BoxDecoration(// color: colorScheme.primary,color: JadeColors.blue_2,// shape: BoxShape.circle,borderRadius: BorderRadius.only(topLeft: Radius.circular(isSelectedDayStart ? 5 : 0),bottomLeft: Radius.circular(isSelectedDayStart ? 5 : 0),topRight: Radius.circular(isSelectedDayEnd ? 5 : 0),bottomRight: Radius.circular(isSelectedDayEnd ? 5 : 0)));if (isRangeSelected widget.selectedDateStart ! widget.selectedDateEnd) {final HighlightPainterStyle style isSelectedDayStart? HighlightPainterStyle.highlightTrailing: HighlightPainterStyle.highlightLeading;highlightPainter HighlightPainter(color: highlightColor,style: style,textDirection: textDirection,);}} else if (isInRange) {// The days within the range get a light background highlight.highlightPainter HighlightPainter(color: highlightColor,style: HighlightPainterStyle.highlightAll,textDirection: textDirection,);} else if (isDisabled) {itemStyle textTheme.bodyText2?.apply(color: colorScheme.onSurface.withOpacity(0.38));} else if (DateUtils.isSameDay(widget.currentDate, dayToBuild)) {// The current day gets a different text color and a circle stroke// border.itemStyle textTheme.bodyText2?.apply(color: colorScheme.primary);decoration BoxDecoration(border: Border.all(color: colorScheme.primary),shape: BoxShape.circle,);}// We want the day of month to be spoken first irrespective of the// locale-specific preferences or TextDirection. This is because// an accessibility user is more likely to be interested in the// day of month before the rest of the date, as they are looking// for the day of month. To do that we prepend day of month to the// formatted full date.String semanticLabel ${localizations.formatDecimal(day)}, ${localizations.formatFullDate(dayToBuild)};if (isSelectedDayStart) {semanticLabel localizations.dateRangeStartDateSemanticLabel(semanticLabel);} else if (isSelectedDayEnd) {semanticLabel localizations.dateRangeEndDateSemanticLabel(semanticLabel);}Widget dayWidget Container(decoration: decoration,child: Center(child: Semantics(label: semanticLabel,selected: isSelectedDayStart || isSelectedDayEnd,child: ExcludeSemantics(child: isSelectedDayStart ?Column(mainAxisAlignment: MainAxisAlignment.center,children: [Text(localizations.formatDecimal(day), style: itemStyle),Text(上架日期, style: TextStyle(color: Colors.white,fontSize: 9.0))],) : isSelectedDayEnd ?Column(mainAxisAlignment: MainAxisAlignment.center,children: [Text(localizations.formatDecimal(day), style: itemStyle),Text(下架日期, style: TextStyle(color: Colors.white,fontSize: 9.0))],) : Text(localizations.formatDecimal(day), style: itemStyle),),),),);if (highlightPainter ! null) {dayWidget CustomPaint(painter: highlightPainter,child: dayWidget,);}if (!isDisabled) {dayWidget InkResponse(focusNode: _dayFocusNodes[day - 1],// onTap: () widget.onChanged(dayToBuild),onTap: () {widget.onChanged(dayToBuild);print(点击天》);},radius: _monthItemRowHeight / 2 4,splashColor: colorScheme.primary.withOpacity(0.38),onFocusChange: _dayFocusChanged,child: dayWidget,);}return dayWidget;}Widget _buildEdgeContainer(BuildContext context, bool isHighlighted) {return Container(color: isHighlighted ? _highlightColor(context) : null);}overrideWidget build(BuildContext context) {final ThemeData themeData Theme.of(context);final TextTheme textTheme themeData.textTheme;final MaterialLocalizations localizations MaterialLocalizations.of(context);final int year widget.displayedMonth.year;final int month widget.displayedMonth.month;final int daysInMonth DateUtils.getDaysInMonth(year, month);final int dayOffset DateUtils.firstDayOffset(year, month, localizations);final int weeks ((daysInMonth dayOffset) / DateTime.daysPerWeek).ceil();final double gridHeight weeks * _monthItemRowHeight (weeks - 1) * _monthItemSpaceBetweenRows;final ListWidget dayItems Widget[];for (int i 0; true; i 1) {// 1-based day of month, e.g. 1-31 for January, and 1-29 for February on// a leap year.final int day i - dayOffset 1;if (day daysInMonth)break;if (day 1) {dayItems.add(Container());} else {final DateTime dayToBuild DateTime(year, month, day);final Widget dayItem _buildDayItem(context,dayToBuild,dayOffset,daysInMonth,);dayItems.add(dayItem);}}// Add the leading/trailing edge containers to each week in order to// correctly extend the range highlight.final ListWidget paddedDayItems Widget[];for (int i 0; i weeks; i) {final int start i * DateTime.daysPerWeek;final int end math.min(start DateTime.daysPerWeek,dayItems.length,);final ListWidget weekList dayItems.sublist(start, end);final DateTime dateAfterLeadingPadding DateTime(year, month, start - dayOffset 1);// Only color the edge container if it is after the start date and// on/before the end date.final bool isLeadingInRange !(dayOffset 0 i 0) widget.selectedDateStart ! null widget.selectedDateEnd ! null dateAfterLeadingPadding.isAfter(widget.selectedDateStart) !dateAfterLeadingPadding.isAfter(widget.selectedDateEnd);weekList.insert(0, _buildEdgeContainer(context, isLeadingInRange));// Only add a trailing edge container if it is for a full week and not a// partial week.if (end dayItems.length || (end dayItems.length dayItems.length % DateTime.daysPerWeek 0)) {final DateTime dateBeforeTrailingPadding DateTime(year, month, end - dayOffset);// Only color the edge container if it is on/after the start date and// before the end date.final bool isTrailingInRange widget.selectedDateStart ! null widget.selectedDateEnd ! null !dateBeforeTrailingPadding.isBefore(widget.selectedDateStart) dateBeforeTrailingPadding.isBefore(widget.selectedDateEnd);weekList.add(_buildEdgeContainer(context, isTrailingInRange));}paddedDayItems.addAll(weekList);}final double maxWidth MediaQuery.of(context).orientation Orientation.landscape? _maxCalendarWidthLandscape: _maxCalendarWidthPortrait;return Column(children: Widget[Container(constraints: BoxConstraints(maxWidth: maxWidth),height: _monthItemHeaderHeight,padding: const EdgeInsets.symmetric(horizontal: 16),alignment: AlignmentDirectional.center,child: ExcludeSemantics(child: Text(localizations.formatMonthYear(widget.displayedMonth),style: textTheme.bodyText2.apply(color: themeData.colorScheme.onSurface),),),),Container(height: 0.5,color: Colors.grey[200]),Container(constraints: BoxConstraints(maxWidth: maxWidth,maxHeight: gridHeight,),child: GridView.custom(physics: const NeverScrollableScrollPhysics(),gridDelegate: const MonthItemGridDelegate(),childrenDelegate: SliverChildListDelegate(paddedDayItems,addRepaintBoundaries: false,),),),const SizedBox(height: _monthItemFooterHeight),],);}
}import package:flutter/rendering.dart;
import dart:math as math;const double _monthItemRowHeight 42.0;
const double _monthItemSpaceBetweenRows 8.0;
const double _horizontalPadding 8.0;class MonthItemGridDelegate extends SliverGridDelegate {const MonthItemGridDelegate();overrideSliverGridLayout getLayout(SliverConstraints constraints) {final double tileWidth (constraints.crossAxisExtent - 2 * _horizontalPadding) / DateTime.daysPerWeek;return _MonthSliverGridLayout(crossAxisCount: DateTime.daysPerWeek 2,dayChildWidth: tileWidth,edgeChildWidth: _horizontalPadding,reverseCrossAxis: axisDirectionIsReversed(constraints.crossAxisDirection),);}overridebool shouldRelayout(MonthItemGridDelegate oldDelegate) false;
}class _MonthSliverGridLayout extends SliverGridLayout {/// Creates a layout that uses equally sized and spaced tiles for each day of/// the week and an additional edge tile for padding at the start and end of/// each row.////// This is necessary to facilitate the painting of the range highlight/// correctly.const _MonthSliverGridLayout({this.crossAxisCount,this.dayChildWidth,this.edgeChildWidth,this.reverseCrossAxis,}) : assert(crossAxisCount ! null crossAxisCount 0),assert(dayChildWidth ! null dayChildWidth 0),assert(edgeChildWidth ! null edgeChildWidth 0),assert(reverseCrossAxis ! null);/// The number of children in the cross axis.final int crossAxisCount;/// The width in logical pixels of the day child widgets.final double dayChildWidth;/// The width in logical pixels of the edge child widgets.final double edgeChildWidth;/// Whether the children should be placed in the opposite order of increasing/// coordinates in the cross axis.////// For example, if the cross axis is horizontal, the children are placed from/// left to right when [reverseCrossAxis] is false and from right to left when/// [reverseCrossAxis] is true.////// Typically set to the return value of [axisDirectionIsReversed] applied to/// the [SliverConstraints.crossAxisDirection].final bool reverseCrossAxis;/// The number of logical pixels from the leading edge of one row to the/// leading edge of the next row.double get _rowHeight {return _monthItemRowHeight _monthItemSpaceBetweenRows;}/// The height in logical pixels of the children widgets.double get _childHeight {return _monthItemRowHeight;}overrideint getMinChildIndexForScrollOffset(double scrollOffset) {return crossAxisCount * (scrollOffset ~/ _rowHeight);}overrideint getMaxChildIndexForScrollOffset(double scrollOffset) {final int mainAxisCount (scrollOffset / _rowHeight).ceil();return math.max(0, crossAxisCount * mainAxisCount - 1);}double _getCrossAxisOffset(double crossAxisStart, bool isPadding) {if (reverseCrossAxis) {return((crossAxisCount - 2) * dayChildWidth 2 * edgeChildWidth) -crossAxisStart -(isPadding ? edgeChildWidth : dayChildWidth);}return crossAxisStart;}overrideSliverGridGeometry getGeometryForChildIndex(int index) {final int adjustedIndex index % crossAxisCount;final bool isEdge adjustedIndex 0 || adjustedIndex crossAxisCount - 1;final double crossAxisStart math.max(0, (adjustedIndex - 1) * dayChildWidth edgeChildWidth);return SliverGridGeometry(scrollOffset: (index ~/ crossAxisCount) * _rowHeight,crossAxisOffset: _getCrossAxisOffset(crossAxisStart, isEdge),mainAxisExtent: _childHeight,crossAxisExtent: isEdge ? edgeChildWidth : dayChildWidth,);}overridedouble computeMaxScrollOffset(int childCount) {assert(childCount 0);final int mainAxisCount ((childCount - 1) ~/ crossAxisCount) 1;final double mainAxisSpacing _rowHeight - _childHeight;return _rowHeight * mainAxisCount - mainAxisSpacing;}
}gif图1效果选择器
import package:jade/customWidget/JadeDateRange/CalendarKeyboardNavigator.dart;
import package:jade/customWidget/JadeDateRange/DayHeaders.dart;
import package:jade/customWidget/JadeDateRange/MonthItem.dart;
import package:flutter/material.dart;
import package:flutter/services.dart;class CalendarDateRangePicker2 extends StatefulWidget {/// Creates a scrollable calendar grid for picking date ranges.CalendarDateRangePicker2({Key key,DateTime initialStartDate,DateTime initialEndDate,DateTime firstDate,DateTime lastDate,DateTime currentDate,bool isAllDisabled,this.blackoutDateTimes,this.onStartDateChanged,this.onEndDateChanged,}) : initialStartDate initialStartDate ! null ? DateUtils.dateOnly(initialStartDate) : null,initialEndDate initialEndDate ! null ? DateUtils.dateOnly(initialEndDate) : null,assert(firstDate ! null),assert(lastDate ! null),firstDate DateUtils.dateOnly(firstDate),lastDate DateUtils.dateOnly(lastDate),currentDate DateUtils.dateOnly(currentDate ?? DateTime.now()),isAllDisabled isAllDisabled ! null ? isAllDisabled : false,super(key: key) {assert(this.initialStartDate null || this.initialEndDate null || !this.initialStartDate.isAfter(initialEndDate),initialStartDate must be on or before initialEndDate.,);assert(!this.lastDate.isBefore(this.firstDate),firstDate must be on or before lastDate.,);}/// The [DateTime] that represents the start of the initial date range selection.DateTime initialStartDate;/// The [DateTime] that represents the end of the initial date range selection.DateTime initialEndDate;/// The earliest allowable [DateTime] that the user can select.final DateTime firstDate;/// The latest allowable [DateTime] that the user can select.final DateTime lastDate;/// The [DateTime] representing today. It will be highlighted in the day grid.final DateTime currentDate;///传入的设置失效的日期置灰、禁用不可点击final ListDateTime blackoutDateTimes;//传入设置日期是否全部禁用bool isAllDisabled;/// Called when the user changes the start date of the selected range.final ValueChangedDateTime onStartDateChanged;/// Called when the user changes the end date of the selected range.final ValueChangedDateTime onEndDateChanged;override_CalendarDateRangePickerState createState() _CalendarDateRangePickerState();
}class _CalendarDateRangePickerState extends StateCalendarDateRangePicker2 {final GlobalKey _scrollViewKey GlobalKey();// DateTime _startDate;// DateTime _endDate;int _initialMonthIndex 0;ScrollController _controller;bool _showWeekBottomDivider;ListDateTime _blackoutDateTimes;overridevoid initState() {super.initState();_controller ScrollController();_controller.addListener(_scrollListener);//利用initState只在初始化时调用一次的特性_startDate、_endDate赋值后不会再次赋值//直接引用widget.initialStartDate、widget.initialEndDate外部传入的参数刷新后对应的相关引用也刷新// _startDate widget.initialStartDate;// _endDate widget.initialEndDate;// Calculate the index for the initially displayed month. This is needed to// divide the list of months into two SliverLists.final DateTime initialDate widget.initialStartDate ?? widget.currentDate;if (!initialDate.isBefore(widget.firstDate) !initialDate.isAfter(widget.lastDate)) {_initialMonthIndex DateUtils.monthDelta(widget.firstDate, initialDate);}_showWeekBottomDivider _initialMonthIndex ! 0;_blackoutDateTimes widget.blackoutDateTimes??[];}overridevoid dispose() {_controller.dispose();super.dispose();}void _scrollListener() {if (_controller.offset _controller.position.minScrollExtent) {setState(() {_showWeekBottomDivider false;});} else if (!_showWeekBottomDivider) {setState(() {_showWeekBottomDivider true;});}}int get _numberOfMonths DateUtils.monthDelta(widget.firstDate, widget.lastDate) 1;void _vibrate() {switch (Theme.of(context).platform) {case TargetPlatform.android:case TargetPlatform.fuchsia:HapticFeedback.vibrate();break;case TargetPlatform.iOS:case TargetPlatform.linux:case TargetPlatform.macOS:case TargetPlatform.windows:break;}}// This updates the selected date range using this logic://// * From the unselected state, selecting one date creates the start date.// * If the next selection is before the start date, reset date range and// set the start date to that selection.// * If the next selection is on or after the start date, set the end date// to that selection.// * After both start and end dates are selected, any subsequent selection// resets the date range and sets start date to that selection.void _updateSelection(DateTime date) {_vibrate();setState(() {if (widget.initialStartDate ! null widget.initialStartDate null !date.isBefore(widget.initialStartDate)) {widget.initialEndDate date;widget.onEndDateChanged?.call(widget.initialEndDate);} else {widget.initialStartDate date;widget.onStartDateChanged?.call(widget.initialStartDate);if (widget.initialStartDate ! null) {widget.initialEndDate null;widget.onEndDateChanged?.call(widget.initialEndDate);}}});}Widget _buildMonthItem(BuildContext context, int index, bool beforeInitialMonth) {final int monthIndex beforeInitialMonth? _initialMonthIndex - index - 1: _initialMonthIndex index;final DateTime month DateUtils.addMonthsToMonthDate(widget.firstDate, monthIndex);return Stack(alignment: Alignment.center,children: [Text(${month.month},style: TextStyle(fontSize: 200,color: Colors.grey.withOpacity(0.1)),),MonthItem(selectedDateStart: widget.initialStartDate,selectedDateEnd: widget.initialEndDate,currentDate: widget.currentDate,firstDate: widget.firstDate,lastDate: widget.lastDate,displayedMonth: month,blackoutDateTimes: _blackoutDateTimes,isAllDisabled: widget.isAllDisabled,onChanged: _updateSelection,)],);}overrideWidget build(BuildContext context) {const Key sliverAfterKey Key(sliverAfterKey);return Column(children: Widget[DayHeaders(),if (_showWeekBottomDivider) const Divider(height: 0),Expanded(child: CalendarKeyboardNavigator(firstDate: widget.firstDate,lastDate: widget.lastDate,initialFocusedDay: widget.initialStartDate ?? widget.initialStartDate ?? widget.currentDate,// In order to prevent performance issues when displaying the// correct initial month, 2 SliverLists are used to split the// months. The first item in the second SliverList is the initial// month to be displayed.child: CustomScrollView(key: _scrollViewKey,controller: _controller,center: sliverAfterKey,slivers: Widget[SliverList(delegate: SliverChildBuilderDelegate((BuildContext context, int index) _buildMonthItem(context, index, true),childCount: _initialMonthIndex,),),SliverList(key: sliverAfterKey,delegate: SliverChildBuilderDelegate((BuildContext context, int index) _buildMonthItem(context, index, false),childCount: _numberOfMonths - _initialMonthIndex,),),],),),),],);}
}gif图2效果选择器
import package:jade/customWidget/JadeDateRange/CalendarKeyboardNavigator.dart;
import package:jade/customWidget/JadeDateRange/DayHeaders.dart;
import package:jade/customWidget/JadeDateRange/MonthItem.dart;
import package:flutter/material.dart;
import package:flutter/rendering.dart;
import package:flutter/services.dart;class CalendarDateRangePicker3 extends StatefulWidget {/// Creates a scrollable calendar grid for picking date ranges.CalendarDateRangePicker3({Key key,DateTime initialStartDate,DateTime initialEndDate,DateTime firstDate,DateTime lastDate,DateTime currentDate,this.onStartDateChanged,this.onEndDateChanged,}) : initialStartDate initialStartDate ! null ? DateUtils.dateOnly(initialStartDate) : null,initialEndDate initialEndDate ! null ? DateUtils.dateOnly(initialEndDate) : null,assert(firstDate ! null),assert(lastDate ! null),firstDate DateUtils.dateOnly(firstDate),lastDate DateUtils.dateOnly(lastDate),currentDate DateUtils.dateOnly(currentDate ?? DateTime.now()),super(key: key) {assert(this.initialStartDate null || this.initialEndDate null || !this.initialStartDate.isAfter(initialEndDate),initialStartDate must be on or before initialEndDate.,);assert(!this.lastDate.isBefore(this.firstDate),firstDate must be on or before lastDate.,);}/// The [DateTime] that represents the start of the initial date range selection.final DateTime initialStartDate;/// The [DateTime] that represents the end of the initial date range selection.final DateTime initialEndDate;/// The earliest allowable [DateTime] that the user can select.final DateTime firstDate;/// The latest allowable [DateTime] that the user can select.final DateTime lastDate;/// The [DateTime] representing today. It will be highlighted in the day grid.final DateTime currentDate;/// Called when the user changes the start date of the selected range.final ValueChangedDateTime onStartDateChanged;/// Called when the user changes the end date of the selected range.final ValueChangedDateTime onEndDateChanged;override_CalendarDateRangePickerState createState() _CalendarDateRangePickerState();
}class _CalendarDateRangePickerState extends StateCalendarDateRangePicker3 {final GlobalKey _scrollViewKey GlobalKey();DateTime _startDate;DateTime _endDate;int _initialMonthIndex 0;ScrollController _controller;bool _showWeekBottomDivider;overridevoid initState() {super.initState();_controller ScrollController();_controller.addListener(_scrollListener);_startDate widget.initialStartDate;_endDate widget.initialEndDate;// Calculate the index for the initially displayed month. This is needed to// divide the list of months into two SliverLists.final DateTime initialDate widget.initialStartDate ?? widget.currentDate;if (!initialDate.isBefore(widget.firstDate) !initialDate.isAfter(widget.lastDate)) {_initialMonthIndex DateUtils.monthDelta(widget.firstDate, initialDate);}_showWeekBottomDivider _initialMonthIndex ! 0;}overridevoid dispose() {_controller.dispose();super.dispose();}void _scrollListener() {if (_controller.offset _controller.position.minScrollExtent) {setState(() {_showWeekBottomDivider false;});} else if (!_showWeekBottomDivider) {setState(() {_showWeekBottomDivider true;});}}int get _numberOfMonths DateUtils.monthDelta(widget.firstDate, widget.lastDate) 1;void _vibrate() {switch (Theme.of(context).platform) {case TargetPlatform.android:case TargetPlatform.fuchsia:HapticFeedback.vibrate();break;case TargetPlatform.iOS:case TargetPlatform.linux:case TargetPlatform.macOS:case TargetPlatform.windows:break;}}// This updates the selected date range using this logic://// * From the unselected state, selecting one date creates the start date.// * If the next selection is before the start date, reset date range and// set the start date to that selection.// * If the next selection is on or after the start date, set the end date// to that selection.// * After both start and end dates are selected, any subsequent selection// resets the date range and sets start date to that selection.void _updateSelection(DateTime date) {_vibrate();setState(() {if (_startDate ! null _endDate null !date.isBefore(_startDate)) {_endDate date;widget.onEndDateChanged?.call(_endDate);} else {_startDate date;widget.onStartDateChanged?.call(_startDate);if (_endDate ! null) {_endDate null;widget.onEndDateChanged?.call(_endDate);}}});}Widget _buildMonthItem(BuildContext context, int index, bool beforeInitialMonth) {final int monthIndex beforeInitialMonth? _initialMonthIndex - index - 1: _initialMonthIndex index;final DateTime month DateUtils.addMonthsToMonthDate(widget.firstDate, monthIndex);return Stack(alignment: Alignment.center,children: [Text(${month.month},style: TextStyle(fontSize: 200,color: Colors.grey.withOpacity(0.1)),),MonthItem(selectedDateStart: _startDate,selectedDateEnd: _endDate,currentDate: widget.currentDate,firstDate: widget.firstDate,lastDate: widget.lastDate,displayedMonth: month,onChanged: _updateSelection,)],);}overrideWidget build(BuildContext context) {const Key sliverAfterKey Key(sliverAfterKey);print(initialEndDate${_endDate.toString()});return Column(children: Widget[DayHeaders(),if (_showWeekBottomDivider) const Divider(height: 0),Expanded(child: CalendarKeyboardNavigator(firstDate: widget.firstDate,lastDate: widget.lastDate,initialFocusedDay: _startDate ?? widget.initialStartDate ?? widget.currentDate,// In order to prevent performance issues when displaying the// correct initial month, 2 SliverLists are used to split the// months. The first item in the second SliverList is the initial// month to be displayed.child: CustomScrollView(key: _scrollViewKey,controller: _controller,center: sliverAfterKey,slivers: Widget[SliverList(delegate: SliverChildBuilderDelegate((BuildContext context, int index) _buildMonthItem(context, index, true),childCount: _initialMonthIndex,),),SliverList(key: sliverAfterKey,delegate: SliverChildBuilderDelegate((BuildContext context, int index) _buildMonthItem(context, index, false),childCount: _numberOfMonths - _initialMonthIndex,),),],),),),],);}
}引用
import package:jade/customWidget/JadeDateRange/JadeDateRangePicker2.dart;
import package:jade/customWidget/JadeDateRange/JadeDateRangePicker3.dart;
import package:jade/utils/JadeColors.dart;
import package:jade/utils/Utils.dart;
import package:widget/custom_appbar.dart;
import package:flutter/material.dart;
import package:flutter_screenutil/flutter_screenutil.dart;class TestSS extends StatefulWidget{overrideStateStatefulWidget createState() {// TODO: implement createStatereturn _SelectTypeDateRange();}
}class _SelectTypeDateRange extends StateTestSS{DateTime _time DateTime.now();DateTime _startDate;DateTime _endDate;DateTimeRange _initDateTimeRange;overridevoid initState() {// TODO: implement initStatesuper.initState();_initDateTimeRange DateTimeRange(start: DateTime(_time.year, 6, 7),end: DateTime(_time.year, 6, 18));}overrideWidget build(BuildContext context) {// TODO: implement buildreturn Scaffold(backgroundColor: Colors.white,appBar: CustomAppBar(backgroundColor: Colors.white,elevation: 0,leading: GestureDetector(onTap: () {Navigator.of(context).pop();},child: Icon(Icons.arrow_back_ios,color: Color(0xff3c3c3c),),),title: Text(选择类型、时间,style: TextStyle(color: Color(0xff333333)),),centerTitle: true,),body: _body());}_body(){return Column(children: [_selectTypeView(),Container(height: 20.w,color: JadeColors.lightGrey),_showDateRangeView(),Expanded(child: _dateRangePickerView()),_btnView()],);}_selectTypeView(){return GestureDetector(child: Container(width: double.infinity,height: 100.w,padding: EdgeInsets.symmetric(horizontal: 30.w),child: Row(children: [Text(选择服务类型,style: TextStyle(fontSize: 28.sp,color: JadeColors.grey_3)),Expanded(child: Text(按月付费类型1个月,style: TextStyle(color: JadeColors.blue_2,fontSize: 28.sp,fontWeight: FontWeight.w600),textAlign: TextAlign.right)),Container(margin: EdgeInsets.only(left: 20.w),child: Image.asset(images/want/yulan_jiantou.png,height: 18.w)),])),onTap: (){});}_showDateRangeView(){return Container(width: double.infinity,height: 100.w,padding: EdgeInsets.only(left: 30.w,right: 40.w),child: Row(children: [Expanded(child: Text(上下架日期,style: TextStyle(fontSize: 28.sp,color: JadeColors.grey_3))),Container(width: 120.w,alignment: Alignment.center,child: Text(_startDate null?上架日期 : ${_startDate.month10?0${_startDate.month}: _startDate.month}.${_startDate.day10?0${_startDate.day}:_startDate.day},style: TextStyle(color: _startDate null ? JadeColors.grey : JadeColors.blue_2,fontSize: 28.sp,fontWeight: FontWeight.w600)),),Container(width: 24.w,height: 4.w,color: JadeColors.grey_7,margin: EdgeInsets.symmetric(horizontal: 30.w)),Container(width: 120.w,alignment: Alignment.center,child: Text(_endDate null?下架日期 : ${_endDate.month10?0${_endDate.month}:_endDate.month}.${_endDate.day10?0${_endDate.day}:_endDate.day},style: TextStyle(color: _endDate null ? JadeColors.grey : JadeColors.blue_2,fontSize: 28.sp,fontWeight: FontWeight.w600)),),]));}_btnView(){return Column(children: [Container(height: 1,color: JadeColors.lightGrey,margin: EdgeInsets.only(bottom: 15.w)),Text(选择上架日期时请确保有充分的时间将样品寄送至体验秀,style: TextStyle(color: JadeColors.grey_3,fontSize: 20.sp),),GestureDetector(child: Container(height: 80.w,width: Utils().screenWidth(context) / 2,alignment: Alignment.center,margin: EdgeInsets.only(top: 15.w,bottom: 60.w),decoration: BoxDecoration(color: JadeColors.blue_2,borderRadius: BorderRadius.circular(50)),child: Text(确认,style: TextStyle(color: Colors.white,fontSize: 32.sp,fontWeight: FontWeight.w600)),),)],);}_dateRangePickerView(){return CalendarDateRangePicker2(// 开始日期firstDate: DateTime(_time.year, _time.month, _time.day),// 结束日期lastDate: DateTime(_time.year 1, 12, 30),// 当前日期currentDate: DateTime.now(),initialStartDate: _initDateTimeRange.start,initialEndDate: _initDateTimeRange.end,blackoutDateTimes: [DateTime(2024, 6, 25),DateTime(2024, 6, 26),DateTime(2024, 6, 28)],isAllDisabled: true,onStartDateChanged: (dateValue) {print(startDate${dateValue.toString()});_startDate dateValue;_endDate _startDate.add(Duration(days: 30));_initDateTimeRange DateTimeRange(start: _startDate,end: _startDate.add(Duration(days: 30)));setState(() {});},onEndDateChanged: (dateValue) {print(endDate${dateValue.toString()});// setState(() {// _endDate dateValue;// });});}
}抽出后未改动的可运行代码 flutter2.10.5环境
// Copyright 2014 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.import dart:math as math;import package:flutter/gestures.dart show DragStartBehavior;
import package:flutter/material.dart;
import package:flutter/rendering.dart;
import package:flutter/services.dart;
import package:flutter/widgets.dart;const Size _calendarPortraitDialogSize Size(330.0, 518.0);
const Size _calendarLandscapeDialogSize Size(496.0, 346.0);
const Size _inputPortraitDialogSize Size(330.0, 270.0);
const Size _inputLandscapeDialogSize Size(496, 160.0);
const Size _inputRangeLandscapeDialogSize Size(496, 164.0);
const Duration _dialogSizeAnimationDuration Duration(milliseconds: 200);
const double _inputFormPortraitHeight 98.0;
const double _inputFormLandscapeHeight 108.0;/// Shows a dialog containing a Material Design date picker.
///
/// The returned [Future] resolves to the date selected by the user when the
/// user confirms the dialog. If the user cancels the dialog, null is returned.
///
/// When the date picker is first displayed, it will show the month of
/// [initialDate], with [initialDate] selected.
///
/// The [firstDate] is the earliest allowable date. The [lastDate] is the latest
/// allowable date. [initialDate] must either fall between these dates,
/// or be equal to one of them. For each of these [DateTime] parameters, only
/// their dates are considered. Their time fields are ignored. They must all
/// be non-null.
///
/// The [currentDate] represents the current day (i.e. today). This
/// date will be highlighted in the day grid. If null, the date of
/// DateTime.now() will be used.
///
/// An optional [initialEntryMode] argument can be used to display the date
/// picker in the [DatePickerEntryMode.calendar] (a calendar month grid)
/// or [DatePickerEntryMode.input] (a text input field) mode.
/// It defaults to [DatePickerEntryMode.calendar] and must be non-null.
///
/// An optional [selectableDayPredicate] function can be passed in to only allow
/// certain days for selection. If provided, only the days that
/// [selectableDayPredicate] returns true for will be selectable. For example,
/// this can be used to only allow weekdays for selection. If provided, it must
/// return true for [initialDate].
///
/// The following optional string parameters allow you to override the default
/// text used for various parts of the dialog:
///
/// * [helpText], label displayed at the top of the dialog.
/// * [cancelText], label on the cancel button.
/// * [confirmText], label on the ok button.
/// * [errorFormatText], message used when the input text isnt in a proper date format.
/// * [errorInvalidText], message used when the input text isnt a selectable date.
/// * [fieldHintText], text used to prompt the user when no text has been entered in the field.
/// * [fieldLabelText], label for the date text input field.
///
/// An optional [locale] argument can be used to set the locale for the date
/// picker. It defaults to the ambient locale provided by [Localizations].
///
/// An optional [textDirection] argument can be used to set the text direction
/// ([TextDirection.ltr] or [TextDirection.rtl]) for the date picker. It
/// defaults to the ambient text direction provided by [Directionality]. If both
/// [locale] and [textDirection] are non-null, [textDirection] overrides the
/// direction chosen for the [locale].
///
/// The [context], [useRootNavigator] and [routeSettings] arguments are passed to
/// [showDialog], the documentation for which discusses how it is used. [context]
/// and [useRootNavigator] must be non-null.
///
/// The [builder] parameter can be used to wrap the dialog widget
/// to add inherited widgets like [Theme].
///
/// An optional [initialDatePickerMode] argument can be used to have the
/// calendar date picker initially appear in the [DatePickerMode.year] or
/// [DatePickerMode.day] mode. It defaults to [DatePickerMode.day], and
/// must be non-null.
///
/// ### State Restoration
///
/// Using this method will not enable state restoration for the date picker.
/// In order to enable state restoration for a date picker, use
/// [Navigator.restorablePush] or [Navigator.restorablePushNamed] with
/// [DatePickerDialog].
///
/// For more information about state restoration, see [RestorationManager].
///
/// {macro flutter.widgets.RestorationManager}
///
/// {tool sample}
/// This sample demonstrates how to create a restorable Material date picker.
/// This is accomplished by enabling state restoration by specifying
/// [MaterialApp.restorationScopeId] and using [Navigator.restorablePush] to
/// push [DatePickerDialog] when the button is tapped.
///
/// ** See code in examples/api/lib/material/date_picker/show_date_picker.0.dart **
/// {end-tool}
///
/// See also:
///
/// * [showDateRangePicker], which shows a material design date range picker
/// used to select a range of dates.
/// * [CalendarDatePicker], which provides the calendar grid used by the date picker dialog.
/// * [InputDatePickerFormField], which provides a text input field for entering dates.
/// * [showTimePicker], which shows a dialog that contains a material design time picker.
///
FutureDateTime showDatePicker({BuildContext context,DateTime initialDate,DateTime firstDate,DateTime lastDate,DateTime currentDate,DatePickerEntryMode initialEntryMode DatePickerEntryMode.calendar,SelectableDayPredicate selectableDayPredicate,String helpText,String cancelText,String confirmText,Locale locale,bool useRootNavigator true,RouteSettings routeSettings,TextDirection textDirection,TransitionBuilder builder,DatePickerMode initialDatePickerMode DatePickerMode.day,String errorFormatText,String errorInvalidText,String fieldHintText,String fieldLabelText,
}) async {assert(context ! null);assert(initialDate ! null);assert(firstDate ! null);assert(lastDate ! null);initialDate DateUtils.dateOnly(initialDate);firstDate DateUtils.dateOnly(firstDate);lastDate DateUtils.dateOnly(lastDate);assert(!lastDate.isBefore(firstDate),lastDate $lastDate must be on or after firstDate $firstDate.,);assert(!initialDate.isBefore(firstDate),initialDate $initialDate must be on or after firstDate $firstDate.,);assert(!initialDate.isAfter(lastDate),initialDate $initialDate must be on or before lastDate $lastDate.,);assert(selectableDayPredicate null || selectableDayPredicate(initialDate),Provided initialDate $initialDate must satisfy provided selectableDayPredicate.,);assert(initialEntryMode ! null);assert(useRootNavigator ! null);assert(initialDatePickerMode ! null);assert(debugCheckHasMaterialLocalizations(context));Widget dialog DatePickerDialog(initialDate: initialDate,firstDate: firstDate,lastDate: lastDate,currentDate: currentDate,initialEntryMode: initialEntryMode,selectableDayPredicate: selectableDayPredicate,helpText: helpText,cancelText: cancelText,confirmText: confirmText,initialCalendarMode: initialDatePickerMode,errorFormatText: errorFormatText,errorInvalidText: errorInvalidText,fieldHintText: fieldHintText,fieldLabelText: fieldLabelText,);if (textDirection ! null) {dialog Directionality(textDirection: textDirection,child: dialog,);}if (locale ! null) {dialog Localizations.override(context: context,locale: locale,child: dialog,);}return showDialogDateTime(context: context,useRootNavigator: useRootNavigator,routeSettings: routeSettings,builder: (BuildContext context) {return builder null ? dialog : builder(context, dialog);},);
}/// A Material-style date picker dialog.
///
/// It is used internally by [showDatePicker] or can be directly pushed
/// onto the [Navigator] stack to enable state restoration. See
/// [showDatePicker] for a state restoration app example.
///
/// See also:
///
/// * [showDatePicker], which is a way to display the date picker.
class DatePickerDialog extends StatefulWidget {/// A Material-style date picker dialog.DatePickerDialog({Key key,DateTime initialDate,DateTime firstDate,DateTime lastDate,DateTime currentDate,this.initialEntryMode DatePickerEntryMode.calendar,this.selectableDayPredicate,this.cancelText,this.confirmText,this.helpText,this.initialCalendarMode DatePickerMode.day,this.errorFormatText,this.errorInvalidText,this.fieldHintText,this.fieldLabelText,this.restorationId,}) : assert(initialDate ! null),assert(firstDate ! null),assert(lastDate ! null),initialDate DateUtils.dateOnly(initialDate),firstDate DateUtils.dateOnly(firstDate),lastDate DateUtils.dateOnly(lastDate),currentDate DateUtils.dateOnly(currentDate ?? DateTime.now()),assert(initialEntryMode ! null),assert(initialCalendarMode ! null),super(key: key) {assert(!this.lastDate.isBefore(this.firstDate),lastDate ${this.lastDate} must be on or after firstDate ${this.firstDate}.,);assert(!this.initialDate.isBefore(this.firstDate),initialDate ${this.initialDate} must be on or after firstDate ${this.firstDate}.,);assert(!this.initialDate.isAfter(this.lastDate),initialDate ${this.initialDate} must be on or before lastDate ${this.lastDate}.,);assert(selectableDayPredicate null || selectableDayPredicate(this.initialDate),Provided initialDate ${this.initialDate} must satisfy provided selectableDayPredicate,);}/// The initially selected [DateTime] that the picker should display.final DateTime initialDate;/// The earliest allowable [DateTime] that the user can select.final DateTime firstDate;/// The latest allowable [DateTime] that the user can select.final DateTime lastDate;/// The [DateTime] representing today. It will be highlighted in the day grid.final DateTime currentDate;/// The initial mode of date entry method for the date picker dialog.////// See [DatePickerEntryMode] for more details on the different data entry/// modes available.final DatePickerEntryMode initialEntryMode;/// Function to provide full control over which [DateTime] can be selected.final SelectableDayPredicate selectableDayPredicate;/// The text that is displayed on the cancel button.final String cancelText;/// The text that is displayed on the confirm button.final String confirmText;/// The text that is displayed at the top of the header.////// This is used to indicate to the user what they are selecting a date for.final String helpText;/// The initial display of the calendar picker.final DatePickerMode initialCalendarMode;/// The error text displayed if the entered date is not in the correct format.final String errorFormatText;/// The error text displayed if the date is not valid.////// A date is not valid if it is earlier than [firstDate], later than/// [lastDate], or doesnt pass the [selectableDayPredicate].final String errorInvalidText;/// The hint text displayed in the [TextField].////// If this is null, it will default to the date format string. For example,/// mm/dd/yyyy for en_US.final String fieldHintText;/// The label text displayed in the [TextField].////// If this is null, it will default to the words representing the date format/// string. For example, Month, Day, Year for en_US.final String fieldLabelText;/// Restoration ID to save and restore the state of the [DatePickerDialog].////// If it is non-null, the date picker will persist and restore the/// date selected on the dialog.////// The state of this widget is persisted in a [RestorationBucket] claimed/// from the surrounding [RestorationScope] using the provided restoration ID.////// See also:////// * [RestorationManager], which explains how state restoration works in/// Flutter.final String restorationId;overrideStateDatePickerDialog createState() _DatePickerDialogState();
}class _DatePickerDialogState extends StateDatePickerDialog with RestorationMixin {RestorableDateTime _selectedDate;_RestorableDatePickerEntryMode _entryMode;final _RestorableAutovalidateMode _autovalidateMode _RestorableAutovalidateMode(AutovalidateMode.disabled);overrideString get restorationId widget.restorationId;overridevoid initState() {// TODO: implement initStatesuper.initState();_selectedDate RestorableDateTime(widget.initialDate);_entryMode _RestorableDatePickerEntryMode(widget.initialEntryMode);}overridevoid restoreState(RestorationBucket oldBucket, bool initialRestore) {registerForRestoration(_selectedDate, selected_date);registerForRestoration(_autovalidateMode, autovalidateMode);registerForRestoration(_entryMode, calendar_entry_mode);}final GlobalKey _calendarPickerKey GlobalKey();final GlobalKeyFormState _formKey GlobalKeyFormState();void _handleOk() {if (_entryMode.value DatePickerEntryMode.input || _entryMode.value DatePickerEntryMode.inputOnly) {final FormState form _formKey.currentState;if (!form.validate()) {setState(() _autovalidateMode.value AutovalidateMode.always);return;}form.save();}Navigator.pop(context, _selectedDate.value);}void _handleCancel() {Navigator.pop(context);}void _handleEntryModeToggle() {setState(() {switch (_entryMode.value) {case DatePickerEntryMode.calendar:_autovalidateMode.value AutovalidateMode.disabled;_entryMode.value DatePickerEntryMode.input;break;case DatePickerEntryMode.input:_formKey.currentState.save();_entryMode.value DatePickerEntryMode.calendar;break;case DatePickerEntryMode.calendarOnly:case DatePickerEntryMode.inputOnly:assert(false, Can not change entry mode from _entryMode);break;}});}void _handleDateChanged(DateTime date) {setState(() {_selectedDate.value date;});}Size _dialogSize(BuildContext context) {final Orientation orientation MediaQuery.of(context).orientation;switch (_entryMode.value) {case DatePickerEntryMode.calendar:case DatePickerEntryMode.calendarOnly:switch (orientation) {case Orientation.portrait:return _calendarPortraitDialogSize;case Orientation.landscape:return _calendarLandscapeDialogSize;}break;case DatePickerEntryMode.input:case DatePickerEntryMode.inputOnly:switch (orientation) {case Orientation.portrait:return _inputPortraitDialogSize;case Orientation.landscape:return _inputLandscapeDialogSize;}}}static const MapShortcutActivator, Intent _formShortcutMap ShortcutActivator, Intent{// Pressing enter on the field will move focus to the next field or control.SingleActivator(LogicalKeyboardKey.enter): NextFocusIntent(),};overrideWidget build(BuildContext context) {final ThemeData theme Theme.of(context);final ColorScheme colorScheme theme.colorScheme;final MaterialLocalizations localizations MaterialLocalizations.of(context);final Orientation orientation MediaQuery.of(context).orientation;final TextTheme textTheme theme.textTheme;// Constrain the textScaleFactor to the largest supported value to prevent// layout issues.final double textScaleFactor math.min(MediaQuery.of(context).textScaleFactor, 1.3);final String dateText localizations.formatMediumDate(_selectedDate.value);final Color onPrimarySurface colorScheme.brightness Brightness.light? colorScheme.onPrimary: colorScheme.onSurface;final TextStyle dateStyle orientation Orientation.landscape? textTheme.headline5?.copyWith(color: onPrimarySurface): textTheme.headline4?.copyWith(color: onPrimarySurface);final Widget actions Container(alignment: AlignmentDirectional.centerEnd,constraints: const BoxConstraints(minHeight: 52.0),padding: const EdgeInsets.symmetric(horizontal: 8),child: OverflowBar(spacing: 8,children: Widget[TextButton(onPressed: _handleCancel,child: Text(widget.cancelText ?? localizations.cancelButtonLabel),),TextButton(onPressed: _handleOk,child: Text(widget.confirmText ?? localizations.okButtonLabel),),],),);CalendarDatePicker calendarDatePicker() {return CalendarDatePicker(key: _calendarPickerKey,initialDate: _selectedDate.value,firstDate: widget.firstDate,lastDate: widget.lastDate,currentDate: widget.currentDate,onDateChanged: _handleDateChanged,selectableDayPredicate: widget.selectableDayPredicate,initialCalendarMode: widget.initialCalendarMode,);}Form inputDatePicker() {return Form(key: _formKey,autovalidateMode: _autovalidateMode.value,child: Container(padding: const EdgeInsets.symmetric(horizontal: 24),height: orientation Orientation.portrait ? _inputFormPortraitHeight : _inputFormLandscapeHeight,child: Shortcuts(shortcuts: _formShortcutMap,child: Column(children: Widget[const Spacer(),InputDatePickerFormField(initialDate: _selectedDate.value,firstDate: widget.firstDate,lastDate: widget.lastDate,onDateSubmitted: _handleDateChanged,onDateSaved: _handleDateChanged,selectableDayPredicate: widget.selectableDayPredicate,errorFormatText: widget.errorFormatText,errorInvalidText: widget.errorInvalidText,fieldHintText: widget.fieldHintText,fieldLabelText: widget.fieldLabelText,autofocus: true,),const Spacer(),],),),),);}Widget picker;Widget entryModeButton;switch (_entryMode.value) {case DatePickerEntryMode.calendar:picker calendarDatePicker();entryModeButton IconButton(icon: const Icon(Icons.edit),color: onPrimarySurface,tooltip: localizations.inputDateModeButtonLabel,onPressed: _handleEntryModeToggle,);break;case DatePickerEntryMode.calendarOnly:picker calendarDatePicker();entryModeButton null;break;case DatePickerEntryMode.input:picker inputDatePicker();entryModeButton IconButton(icon: const Icon(Icons.calendar_today),color: onPrimarySurface,tooltip: localizations.calendarModeButtonLabel,onPressed: _handleEntryModeToggle,);break;case DatePickerEntryMode.inputOnly:picker inputDatePicker();entryModeButton null;break;}final Widget header _DatePickerHeader(helpText: widget.helpText ?? localizations.datePickerHelpText,titleText: dateText,titleStyle: dateStyle,orientation: orientation,isShort: orientation Orientation.landscape,entryModeButton: entryModeButton,);final Size dialogSize _dialogSize(context) * textScaleFactor;return Dialog(insetPadding: const EdgeInsets.symmetric(horizontal: 16.0, vertical: 24.0),clipBehavior: Clip.antiAlias,child: AnimatedContainer(width: dialogSize.width,height: dialogSize.height,duration: _dialogSizeAnimationDuration,curve: Curves.easeIn,child: MediaQuery(data: MediaQuery.of(context).copyWith(textScaleFactor: textScaleFactor,),child: Builder(builder: (BuildContext context) {switch (orientation) {case Orientation.portrait:return Column(mainAxisSize: MainAxisSize.min,crossAxisAlignment: CrossAxisAlignment.stretch,children: Widget[header,Expanded(child: picker),actions,],);case Orientation.landscape:return Row(mainAxisSize: MainAxisSize.min,crossAxisAlignment: CrossAxisAlignment.stretch,children: Widget[header,Flexible(child: Column(mainAxisSize: MainAxisSize.min,crossAxisAlignment: CrossAxisAlignment.stretch,children: Widget[Expanded(child: picker),actions,],),),],);}}),),),);}
}// A restorable [DatePickerEntryMode] value.
//
// This serializes each entry as a unique int value.
class _RestorableDatePickerEntryMode extends RestorableValueDatePickerEntryMode {_RestorableDatePickerEntryMode(DatePickerEntryMode defaultValue,) : _defaultValue defaultValue;final DatePickerEntryMode _defaultValue;overrideDatePickerEntryMode createDefaultValue() _defaultValue;overridevoid didUpdateValue(DatePickerEntryMode oldValue) {assert(debugIsSerializableForRestoration(value.index));notifyListeners();}overrideDatePickerEntryMode fromPrimitives(Object data) DatePickerEntryMode.values[data as int];overrideObject toPrimitives() value.index;
}// A restorable [AutovalidateMode] value.
//
// This serializes each entry as a unique int value.
class _RestorableAutovalidateMode extends RestorableValueAutovalidateMode {_RestorableAutovalidateMode(AutovalidateMode defaultValue,) : _defaultValue defaultValue;final AutovalidateMode _defaultValue;overrideAutovalidateMode createDefaultValue() _defaultValue;overridevoid didUpdateValue(AutovalidateMode oldValue) {assert(debugIsSerializableForRestoration(value.index));notifyListeners();}overrideAutovalidateMode fromPrimitives(Object data) AutovalidateMode.values[data as int];overrideObject toPrimitives() value.index;
}/// Re-usable widget that displays the selected date (in large font) and the
/// help text above it.
///
/// These types include:
///
/// * Single Date picker with calendar mode.
/// * Single Date picker with text input mode.
/// * Date Range picker with text input mode.
///
/// [helpText], [orientation], [icon], [onIconPressed] are required and must be
/// non-null.
class _DatePickerHeader extends StatelessWidget {/// Creates a header for use in a date picker dialog.const _DatePickerHeader({Key key,this.helpText,this.titleText,this.titleSemanticsLabel,this.titleStyle,this.orientation,this.isShort false,this.entryModeButton,}) : assert(helpText ! null),assert(orientation ! null),assert(isShort ! null),super(key: key);static const double _datePickerHeaderLandscapeWidth 152.0;static const double _datePickerHeaderPortraitHeight 120.0;static const double _headerPaddingLandscape 16.0;/// The text that is displayed at the top of the header.////// This is used to indicate to the user what they are selecting a date for.final String helpText;/// The text that is displayed at the center of the header.final String titleText;/// The semantic label associated with the [titleText].final String titleSemanticsLabel;/// The [TextStyle] that the title text is displayed with.final TextStyle titleStyle;/// The orientation is used to decide how to layout its children.final Orientation orientation;/// Indicates the header is being displayed in a shorter/narrower context.////// This will be used to tighten up the space between the help text and date/// text if true. Additionally, it will use a smaller typography style if/// true.////// This is necessary for displaying the manual input mode in/// landscape orientation, in order to account for the keyboard height.final bool isShort;final Widget entryModeButton;overrideWidget build(BuildContext context) {final ThemeData theme Theme.of(context);final ColorScheme colorScheme theme.colorScheme;final TextTheme textTheme theme.textTheme;// The header should use the primary color in light themes and surface color in darkfinal bool isDark colorScheme.brightness Brightness.dark;final Color primarySurfaceColor isDark ? colorScheme.surface : colorScheme.primary;final Color onPrimarySurfaceColor isDark ? colorScheme.onSurface : colorScheme.onPrimary;final TextStyle helpStyle textTheme.overline?.copyWith(color: onPrimarySurfaceColor,);final Text help Text(helpText,style: helpStyle,maxLines: 1,overflow: TextOverflow.ellipsis,);final Text title Text(titleText,semanticsLabel: titleSemanticsLabel ?? titleText,style: titleStyle,maxLines: orientation Orientation.portrait ? 1 : 2,overflow: TextOverflow.ellipsis,);switch (orientation) {case Orientation.portrait:return SizedBox(height: _datePickerHeaderPortraitHeight,child: Material(color: primarySurfaceColor,child: Padding(padding: const EdgeInsetsDirectional.only(start: 24,end: 12,),child: Column(crossAxisAlignment: CrossAxisAlignment.start,children: Widget[const SizedBox(height: 16),help,const Flexible(child: SizedBox(height: 38)),Row(children: Widget[Expanded(child: title),if (entryModeButton ! null)entryModeButton,],),],),),),);case Orientation.landscape:return SizedBox(width: _datePickerHeaderLandscapeWidth,child: Material(color: primarySurfaceColor,child: Column(crossAxisAlignment: CrossAxisAlignment.start,children: Widget[const SizedBox(height: 16),Padding(padding: const EdgeInsets.symmetric(horizontal: _headerPaddingLandscape,),child: help,),SizedBox(height: isShort ? 16 : 56),Expanded(child: Padding(padding: const EdgeInsets.symmetric(horizontal: _headerPaddingLandscape,),child: title,),),if (entryModeButton ! null)Padding(padding: const EdgeInsets.symmetric(horizontal: 4),child: entryModeButton,),],),),);}}
}/// Shows a full screen modal dialog containing a Material Design date range
/// picker.
///
/// The returned [Future] resolves to the [DateTimeRange] selected by the user
/// when the user saves their selection. If the user cancels the dialog, null is
/// returned.
///
/// If [initialDateRange] is non-null, then it will be used as the initially
/// selected date range. If it is provided, initialDateRange.start must be
/// before or on initialDateRange.end.
///
/// The [firstDate] is the earliest allowable date. The [lastDate] is the latest
/// allowable date. Both must be non-null.
///
/// If an initial date range is provided, initialDateRange.start
/// and initialDateRange.end must both fall between or on [firstDate] and
/// [lastDate]. For all of these [DateTime] values, only their dates are
/// considered. Their time fields are ignored.
///
/// The [currentDate] represents the current day (i.e. today). This
/// date will be highlighted in the day grid. If null, the date of
/// DateTime.now() will be used.
///
/// An optional [initialEntryMode] argument can be used to display the date
/// picker in the [DatePickerEntryMode.calendar] (a scrollable calendar month
/// grid) or [DatePickerEntryMode.input] (two text input fields) mode.
/// It defaults to [DatePickerEntryMode.calendar] and must be non-null.
///
/// The following optional string parameters allow you to override the default
/// text used for various parts of the dialog:
///
/// * [helpText], the label displayed at the top of the dialog.
/// * [cancelText], the label on the cancel button for the text input mode.
/// * [confirmText],the label on the ok button for the text input mode.
/// * [saveText], the label on the save button for the fullscreen calendar
/// mode.
/// * [errorFormatText], the message used when an input text isnt in a proper
/// date format.
/// * [errorInvalidText], the message used when an input text isnt a
/// selectable date.
/// * [errorInvalidRangeText], the message used when the date range is
/// invalid (e.g. start date is after end date).
/// * [fieldStartHintText], the text used to prompt the user when no text has
/// been entered in the start field.
/// * [fieldEndHintText], the text used to prompt the user when no text has
/// been entered in the end field.
/// * [fieldStartLabelText], the label for the start date text input field.
/// * [fieldEndLabelText], the label for the end date text input field.
///
/// An optional [locale] argument can be used to set the locale for the date
/// picker. It defaults to the ambient locale provided by [Localizations].
///
/// An optional [textDirection] argument can be used to set the text direction
/// ([TextDirection.ltr] or [TextDirection.rtl]) for the date picker. It
/// defaults to the ambient text direction provided by [Directionality]. If both
/// [locale] and [textDirection] are non-null, [textDirection] overrides the
/// direction chosen for the [locale].
///
/// The [context], [useRootNavigator] and [routeSettings] arguments are passed
/// to [showDialog], the documentation for which discusses how it is used.
/// [context] and [useRootNavigator] must be non-null.
///
/// The [builder] parameter can be used to wrap the dialog widget
/// to add inherited widgets like [Theme].
///
/// ### State Restoration
///
/// Using this method will not enable state restoration for the date range picker.
/// In order to enable state restoration for a date range picker, use
/// [Navigator.restorablePush] or [Navigator.restorablePushNamed] with
/// [DateRangePickerDialog].
///
/// For more information about state restoration, see [RestorationManager].
///
/// {macro flutter.widgets.RestorationManager}
///
/// {tool sample}
/// This sample demonstrates how to create a restorable Material date range picker.
/// This is accomplished by enabling state restoration by specifying
/// [MaterialApp.restorationScopeId] and using [Navigator.restorablePush] to
/// push [DateRangePickerDialog] when the button is tapped.
///
/// ** See code in examples/api/lib/material/date_picker/show_date_range_picker.0.dart **
/// {end-tool}
///
/// See also:
///
/// * [showDatePicker], which shows a material design date picker used to
/// select a single date.
/// * [DateTimeRange], which is used to describe a date range.
///
FutureDateTimeRange showDateRangePickerA({BuildContext context,DateTimeRange initialDateRange,DateTime firstDate,DateTime lastDate,DateTime currentDate,DatePickerEntryMode initialEntryMode DatePickerEntryMode.calendar,String helpText,String cancelText,String confirmText,String saveText,String errorFormatText,String errorInvalidText,String errorInvalidRangeText,String fieldStartHintText,String fieldEndHintText,String fieldStartLabelText,String fieldEndLabelText,Locale locale,bool useRootNavigator true,RouteSettings routeSettings,TextDirection textDirection,TransitionBuilder builder,
}) async {assert(context ! null);assert(initialDateRange null || (initialDateRange.start ! null initialDateRange.end ! null),initialDateRange must be null or have non-null start and end dates.,);assert(initialDateRange null || !initialDateRange.start.isAfter(initialDateRange.end),initialDateRanges start date must not be after its end date.,);initialDateRange initialDateRange null ? null : DateUtils.datesOnly(initialDateRange);assert(firstDate ! null);firstDate DateUtils.dateOnly(firstDate);assert(lastDate ! null);lastDate DateUtils.dateOnly(lastDate);assert(!lastDate.isBefore(firstDate),lastDate $lastDate must be on or after firstDate $firstDate.,);assert(initialDateRange null || !initialDateRange.start.isBefore(firstDate),initialDateRanges start date must be on or after firstDate $firstDate.,);assert(initialDateRange null || !initialDateRange.end.isBefore(firstDate),initialDateRanges end date must be on or after firstDate $firstDate.,);assert(initialDateRange null || !initialDateRange.start.isAfter(lastDate),initialDateRanges start date must be on or before lastDate $lastDate.,);assert(initialDateRange null || !initialDateRange.end.isAfter(lastDate),initialDateRanges end date must be on or before lastDate $lastDate.,);currentDate DateUtils.dateOnly(currentDate ?? DateTime.now());assert(initialEntryMode ! null);assert(useRootNavigator ! null);assert(debugCheckHasMaterialLocalizations(context));Widget dialog DateRangePickerDialog(initialDateRange: initialDateRange,firstDate: firstDate,lastDate: lastDate,currentDate: currentDate,initialEntryMode: initialEntryMode,helpText: helpText,cancelText: cancelText,confirmText: confirmText,saveText: saveText,errorFormatText: errorFormatText,errorInvalidText: errorInvalidText,errorInvalidRangeText: errorInvalidRangeText,fieldStartHintText: fieldStartHintText,fieldEndHintText: fieldEndHintText,fieldStartLabelText: fieldStartLabelText,fieldEndLabelText: fieldEndLabelText,);if (textDirection ! null) {dialog Directionality(textDirection: textDirection,child: dialog,);}if (locale ! null) {dialog Localizations.override(context: context,locale: locale,child: dialog,);}return showDialogDateTimeRange(context: context,useRootNavigator: useRootNavigator,routeSettings: routeSettings,useSafeArea: false,builder: (BuildContext context) {return builder null ? dialog : builder(context, dialog);},);
}/// Returns a locale-appropriate string to describe the start of a date range.
///
/// If startDate is null, then it defaults to Start Date, otherwise if it
/// is in the same year as the endDate then it will use the short month
/// day format (i.e. Jan 21). Otherwise it will return the short date format
/// (i.e. Jan 21, 2020).
String _formatRangeStartDate(MaterialLocalizations localizations, DateTime startDate, DateTime endDate) {return startDate null? localizations.dateRangeStartLabel: (endDate null || startDate.year endDate.year)? localizations.formatShortMonthDay(startDate): localizations.formatShortDate(startDate);
}/// Returns an locale-appropriate string to describe the end of a date range.
///
/// If endDate is null, then it defaults to End Date, otherwise if it
/// is in the same year as the startDate and the currentDate then it will
/// just use the short month day format (i.e. Jan 21), otherwise it will
/// include the year (i.e. Jan 21, 2020).
String _formatRangeEndDate(MaterialLocalizations localizations, DateTime startDate, DateTime endDate, DateTime currentDate) {return endDate null? localizations.dateRangeEndLabel: (startDate ! null startDate.year endDate.year startDate.year currentDate.year)? localizations.formatShortMonthDay(endDate): localizations.formatShortDate(endDate);
}/// A Material-style date range picker dialog.
///
/// It is used internally by [showDateRangePicker] or can be directly pushed
/// onto the [Navigator] stack to enable state restoration. See
/// [showDateRangePicker] for a state restoration app example.
///
/// See also:
///
/// * [showDateRangePicker], which is a way to display the date picker.
class DateRangePickerDialog extends StatefulWidget {/// A Material-style date range picker dialog.const DateRangePickerDialog({Key key,this.initialDateRange,this.firstDate,this.lastDate,this.currentDate,this.initialEntryMode DatePickerEntryMode.calendar,this.helpText,this.cancelText,this.confirmText,this.saveText,this.errorInvalidRangeText,this.errorFormatText,this.errorInvalidText,this.fieldStartHintText,this.fieldEndHintText,this.fieldStartLabelText,this.fieldEndLabelText,this.restorationId,}) : super(key: key);/// The date range that the date range picker starts with when it opens.////// If an initial date range is provided, initialDateRange.start/// and initialDateRange.end must both fall between or on [firstDate] and/// [lastDate]. For all of these [DateTime] values, only their dates are/// considered. Their time fields are ignored.////// If [initialDateRange] is non-null, then it will be used as the initially/// selected date range. If it is provided, initialDateRange.start must be/// before or on initialDateRange.end.final DateTimeRange initialDateRange;/// The earliest allowable date on the date range.final DateTime firstDate;/// The latest allowable date on the date range.final DateTime lastDate;/// The [currentDate] represents the current day (i.e. today).////// This date will be highlighted in the day grid.////// If null, the date of DateTime.now() will be used.final DateTime currentDate;/// The initial date range picker entry mode.////// The date range has two main modes: [DatePickerEntryMode.calendar] (a/// scrollable calendar month grid) or [DatePickerEntryMode.input] (two text/// input fields) mode.////// It defaults to [DatePickerEntryMode.calendar] and must be non-null.final DatePickerEntryMode initialEntryMode;/// The label on the cancel button for the text input mode.////// If null, the localized value of/// [MaterialLocalizations.cancelButtonLabel] is used.final String cancelText;/// The label on the OK button for the text input mode.////// If null, the localized value of/// [MaterialLocalizations.okButtonLabel] is used.final String confirmText;/// The label on the save button for the fullscreen calendar mode.////// If null, the localized value of/// [MaterialLocalizations.saveButtonLabel] is used.final String saveText;/// The label displayed at the top of the dialog.////// If null, the localized value of/// [MaterialLocalizations.dateRangePickerHelpText] is used.final String helpText;/// The message used when the date range is invalid (e.g. start date is after/// end date).////// If null, the localized value of/// [MaterialLocalizations.invalidDateRangeLabel] is used.final String errorInvalidRangeText;/// The message used when an input text isnt in a proper date format.////// If null, the localized value of/// [MaterialLocalizations.invalidDateFormatLabel] is used.final String errorFormatText;/// The message used when an input text isnt a selectable date.////// If null, the localized value of/// [MaterialLocalizations.dateOutOfRangeLabel] is used.final String errorInvalidText;/// The text used to prompt the user when no text has been entered in the/// start field.////// If null, the localized value of/// [MaterialLocalizations.dateHelpText] is used.final String fieldStartHintText;/// The text used to prompt the user when no text has been entered in the/// end field.////// If null, the localized value of [MaterialLocalizations.dateHelpText] is/// used.final String fieldEndHintText;/// The label for the start date text input field.////// If null, the localized value of [MaterialLocalizations.dateRangeStartLabel]/// is used.final String fieldStartLabelText;/// The label for the end date text input field.////// If null, the localized value of [MaterialLocalizations.dateRangeEndLabel]/// is used.final String fieldEndLabelText;/// Restoration ID to save and restore the state of the [DateRangePickerDialog].////// If it is non-null, the date range picker will persist and restore the/// date range selected on the dialog.////// The state of this widget is persisted in a [RestorationBucket] claimed/// from the surrounding [RestorationScope] using the provided restoration ID.////// See also:////// * [RestorationManager], which explains how state restoration works in/// Flutter.final String restorationId;overrideStateDateRangePickerDialog createState() _DateRangePickerDialogState();
}class _DateRangePickerDialogState extends StateDateRangePickerDialog with RestorationMixin {_RestorableDatePickerEntryMode _entryMode;RestorableDateTimeN _selectedStart;RestorableDateTimeN _selectedEnd;final RestorableBool _autoValidate RestorableBool(false);final GlobalKey _calendarPickerKey GlobalKey();final GlobalKey_InputDateRangePickerState _inputPickerKey GlobalKey_InputDateRangePickerState();overridevoid initState() {// TODO: implement initStatesuper.initState();_entryMode _RestorableDatePickerEntryMode(widget.initialEntryMode);_selectedStart RestorableDateTimeN(widget.initialDateRange?.start);_selectedEnd RestorableDateTimeN(widget.initialDateRange?.end);}overrideString get restorationId widget.restorationId;overridevoid restoreState(RestorationBucket oldBucket, bool initialRestore) {registerForRestoration(_entryMode, entry_mode);registerForRestoration(_selectedStart, selected_start);registerForRestoration(_selectedEnd, selected_end);registerForRestoration(_autoValidate, autovalidate);}void _handleOk() {if (_entryMode.value DatePickerEntryMode.input || _entryMode.value DatePickerEntryMode.inputOnly) {final _InputDateRangePickerState picker _inputPickerKey.currentState;if (!picker.validate()) {setState(() {_autoValidate.value true;});return;}}final DateTimeRange selectedRange _hasSelectedDateRange? DateTimeRange(start: _selectedStart.value, end: _selectedEnd.value): null;Navigator.pop(context, selectedRange);}void _handleCancel() {Navigator.pop(context);}void _handleEntryModeToggle() {setState(() {switch (_entryMode.value) {case DatePickerEntryMode.calendar:_autoValidate.value false;_entryMode.value DatePickerEntryMode.input;break;case DatePickerEntryMode.input:// Validate the range datesif (_selectedStart.value ! null (_selectedStart.value.isBefore(widget.firstDate) || _selectedStart.value.isAfter(widget.lastDate))) {_selectedStart.value null;// With no valid start date, having an end date makes no sense for the UI._selectedEnd.value null;}if (_selectedEnd.value ! null (_selectedEnd.value.isBefore(widget.firstDate) || _selectedEnd.value.isAfter(widget.lastDate))) {_selectedEnd.value null;}// If invalid range (start after end), then just use the start dateif (_selectedStart.value ! null _selectedEnd.value ! null _selectedStart.value.isAfter(_selectedEnd.value)) {_selectedEnd.value null;}_entryMode.value DatePickerEntryMode.calendar;break;case DatePickerEntryMode.calendarOnly:case DatePickerEntryMode.inputOnly:assert(false, Can not change entry mode from $_entryMode);break;}});}void _handleStartDateChanged(DateTime date) {setState(() _selectedStart.value date);}void _handleEndDateChanged(DateTime date) {setState(() _selectedEnd.value date);}bool get _hasSelectedDateRange _selectedStart.value ! null _selectedEnd.value ! null;overrideWidget build(BuildContext context) {final MediaQueryData mediaQuery MediaQuery.of(context);final Orientation orientation mediaQuery.orientation;final double textScaleFactor math.min(mediaQuery.textScaleFactor, 1.3);final MaterialLocalizations localizations MaterialLocalizations.of(context);final ColorScheme colors Theme.of(context).colorScheme;final Color onPrimarySurface colors.brightness Brightness.light? colors.onPrimary: colors.onSurface;Widget contents;Size size;ShapeBorder shape;double elevation;EdgeInsets insetPadding;final bool showEntryModeButton _entryMode.value DatePickerEntryMode.calendar ||_entryMode.value DatePickerEntryMode.input;switch (_entryMode.value) {case DatePickerEntryMode.calendar:case DatePickerEntryMode.calendarOnly:contents _CalendarRangePickerDialog(key: _calendarPickerKey,selectedStartDate: _selectedStart.value,selectedEndDate: _selectedEnd.value,firstDate: widget.firstDate,lastDate: widget.lastDate,currentDate: widget.currentDate,onStartDateChanged: _handleStartDateChanged,onEndDateChanged: _handleEndDateChanged,onConfirm: _hasSelectedDateRange ? _handleOk : null,onCancel: _handleCancel,entryModeButton: showEntryModeButton? IconButton(icon: const Icon(Icons.edit),padding: EdgeInsets.zero,color: onPrimarySurface,tooltip: localizations.inputDateModeButtonLabel,onPressed: _handleEntryModeToggle,): null,confirmText: widget.saveText ?? localizations.saveButtonLabel,helpText: widget.helpText ?? localizations.dateRangePickerHelpText,);size mediaQuery.size;insetPadding EdgeInsets.zero;shape const RoundedRectangleBorder();elevation 0;break;case DatePickerEntryMode.input:case DatePickerEntryMode.inputOnly:contents _InputDateRangePickerDialog(selectedStartDate: _selectedStart.value,selectedEndDate: _selectedEnd.value,currentDate: widget.currentDate,picker: Container(padding: const EdgeInsets.symmetric(horizontal: 24),height: orientation Orientation.portrait? _inputFormPortraitHeight: _inputFormLandscapeHeight,child: Column(children: Widget[const Spacer(),_InputDateRangePicker(key: _inputPickerKey,initialStartDate: _selectedStart.value,initialEndDate: _selectedEnd.value,firstDate: widget.firstDate,lastDate: widget.lastDate,onStartDateChanged: _handleStartDateChanged,onEndDateChanged: _handleEndDateChanged,autofocus: true,autovalidate: _autoValidate.value,helpText: widget.helpText,errorInvalidRangeText: widget.errorInvalidRangeText,errorFormatText: widget.errorFormatText,errorInvalidText: widget.errorInvalidText,fieldStartHintText: widget.fieldStartHintText,fieldEndHintText: widget.fieldEndHintText,fieldStartLabelText: widget.fieldStartLabelText,fieldEndLabelText: widget.fieldEndLabelText,),const Spacer(),],),),onConfirm: _handleOk,onCancel: _handleCancel,entryModeButton: showEntryModeButton? IconButton(icon: const Icon(Icons.calendar_today),padding: EdgeInsets.zero,color: onPrimarySurface,tooltip: localizations.calendarModeButtonLabel,onPressed: _handleEntryModeToggle,): null,confirmText: widget.confirmText ?? localizations.okButtonLabel,cancelText: widget.cancelText ?? localizations.cancelButtonLabel,helpText: widget.helpText ?? localizations.dateRangePickerHelpText,);final DialogTheme dialogTheme Theme.of(context).dialogTheme;size orientation Orientation.portrait ? _inputPortraitDialogSize : _inputRangeLandscapeDialogSize;insetPadding const EdgeInsets.symmetric(horizontal: 16.0, vertical: 24.0);shape dialogTheme.shape;elevation dialogTheme.elevation ?? 24;break;}return Dialog(insetPadding: insetPadding,shape: shape,elevation: elevation,clipBehavior: Clip.antiAlias,child: AnimatedContainer(width: size.width,height: size.height,duration: _dialogSizeAnimationDuration,curve: Curves.easeIn,child: MediaQuery(data: MediaQuery.of(context).copyWith(textScaleFactor: textScaleFactor,),child: Builder(builder: (BuildContext context) {return contents;}),),),);}
}class _CalendarRangePickerDialog extends StatelessWidget {const _CalendarRangePickerDialog({Key key,this.selectedStartDate,this.selectedEndDate,this.firstDate,this.lastDate,this.currentDate,this.onStartDateChanged,this.onEndDateChanged,this.onConfirm,this.onCancel,this.confirmText,this.helpText,this.entryModeButton,}) : super(key: key);final DateTime selectedStartDate;final DateTime selectedEndDate;final DateTime firstDate;final DateTime lastDate;final DateTime currentDate;final ValueChangedDateTime onStartDateChanged;final ValueChangedDateTime onEndDateChanged;final VoidCallback onConfirm;final VoidCallback onCancel;final String confirmText;final String helpText;final Widget entryModeButton;overrideWidget build(BuildContext context) {final ThemeData theme Theme.of(context);final ColorScheme colorScheme theme.colorScheme;final MaterialLocalizations localizations MaterialLocalizations.of(context);final Orientation orientation MediaQuery.of(context).orientation;final TextTheme textTheme theme.textTheme;final Color headerForeground colorScheme.brightness Brightness.light? colorScheme.onPrimary: colorScheme.onSurface;final Color headerDisabledForeground headerForeground.withOpacity(0.38);final String startDateText _formatRangeStartDate(localizations, selectedStartDate, selectedEndDate);final String endDateText _formatRangeEndDate(localizations, selectedStartDate, selectedEndDate, DateTime.now());final TextStyle headlineStyle textTheme.headline5;final TextStyle startDateStyle headlineStyle?.apply(color: selectedStartDate ! null ? headerForeground : headerDisabledForeground,);final TextStyle endDateStyle headlineStyle?.apply(color: selectedEndDate ! null ? headerForeground : headerDisabledForeground,);final TextStyle saveButtonStyle textTheme.button.apply(color: onConfirm ! null ? headerForeground : headerDisabledForeground,);return SafeArea(top: false,left: false,right: false,child: Scaffold(appBar: AppBar(leading: CloseButton(onPressed: onCancel,),actions: Widget[if (orientation Orientation.landscape entryModeButton ! null)entryModeButton,TextButton(onPressed: onConfirm,child: Text(confirmText, style: saveButtonStyle),),const SizedBox(width: 8),],bottom: PreferredSize(preferredSize: const Size(double.infinity, 64),child: Row(children: Widget[SizedBox(width: MediaQuery.of(context).size.width 360 ? 42 : 72),Expanded(child: Semantics(label: $helpText $startDateText to $endDateText,excludeSemantics: true,child: Column(crossAxisAlignment: CrossAxisAlignment.start,children: Widget[Text(helpText,style: textTheme.overline.apply(color: headerForeground,),),const SizedBox(height: 8),Row(children: Widget[Text(startDateText,style: startDateStyle,maxLines: 1,overflow: TextOverflow.ellipsis,),Text( – , style: startDateStyle,),Flexible(child: Text(endDateText,style: endDateStyle,maxLines: 1,overflow: TextOverflow.ellipsis,),),],),const SizedBox(height: 16),],),),),if (orientation Orientation.portrait entryModeButton ! null)Padding(padding: const EdgeInsets.symmetric(horizontal: 8.0),child: entryModeButton,),]),),),body: _CalendarDateRangePicker(initialStartDate: selectedStartDate,initialEndDate: selectedEndDate,firstDate: firstDate,lastDate: lastDate,currentDate: currentDate,onStartDateChanged: onStartDateChanged,onEndDateChanged: onEndDateChanged,),),);}
}const Duration _monthScrollDuration Duration(milliseconds: 200);const double _monthItemHeaderHeight 58.0;
const double _monthItemFooterHeight 12.0;
const double _monthItemRowHeight 42.0;
const double _monthItemSpaceBetweenRows 8.0;
const double _horizontalPadding 8.0;
const double _maxCalendarWidthLandscape 384.0;
const double _maxCalendarWidthPortrait 480.0;/// Displays a scrollable calendar grid that allows a user to select a range
/// of dates.
class _CalendarDateRangePicker extends StatefulWidget {/// Creates a scrollable calendar grid for picking date ranges._CalendarDateRangePicker({Key key,DateTime initialStartDate,DateTime initialEndDate,DateTime firstDate,DateTime lastDate,DateTime currentDate,this.onStartDateChanged,this.onEndDateChanged,}) : initialStartDate initialStartDate ! null ? DateUtils.dateOnly(initialStartDate) : null,initialEndDate initialEndDate ! null ? DateUtils.dateOnly(initialEndDate) : null,assert(firstDate ! null),assert(lastDate ! null),firstDate DateUtils.dateOnly(firstDate),lastDate DateUtils.dateOnly(lastDate),currentDate DateUtils.dateOnly(currentDate ?? DateTime.now()),super(key: key) {assert(this.initialStartDate null || this.initialEndDate null || !this.initialStartDate.isAfter(initialEndDate),initialStartDate must be on or before initialEndDate.,);assert(!this.lastDate.isBefore(this.firstDate),firstDate must be on or before lastDate.,);}/// The [DateTime] that represents the start of the initial date range selection.final DateTime initialStartDate;/// The [DateTime] that represents the end of the initial date range selection.final DateTime initialEndDate;/// The earliest allowable [DateTime] that the user can select.final DateTime firstDate;/// The latest allowable [DateTime] that the user can select.final DateTime lastDate;/// The [DateTime] representing today. It will be highlighted in the day grid.final DateTime currentDate;/// Called when the user changes the start date of the selected range.final ValueChangedDateTime onStartDateChanged;/// Called when the user changes the end date of the selected range.final ValueChangedDateTime onEndDateChanged;override_CalendarDateRangePickerState createState() _CalendarDateRangePickerState();
}class _CalendarDateRangePickerState extends State_CalendarDateRangePicker {final GlobalKey _scrollViewKey GlobalKey();DateTime _startDate;DateTime _endDate;int _initialMonthIndex 0;ScrollController _controller;bool _showWeekBottomDivider;overridevoid initState() {super.initState();_controller ScrollController();_controller.addListener(_scrollListener);_startDate widget.initialStartDate;_endDate widget.initialEndDate;// Calculate the index for the initially displayed month. This is needed to// divide the list of months into two SliverLists.final DateTime initialDate widget.initialStartDate ?? widget.currentDate;if (!initialDate.isBefore(widget.firstDate) !initialDate.isAfter(widget.lastDate)) {_initialMonthIndex DateUtils.monthDelta(widget.firstDate, initialDate);}_showWeekBottomDivider _initialMonthIndex ! 0;}overridevoid dispose() {_controller.dispose();super.dispose();}void _scrollListener() {if (_controller.offset _controller.position.minScrollExtent) {setState(() {_showWeekBottomDivider false;});} else if (!_showWeekBottomDivider) {setState(() {_showWeekBottomDivider true;});}}int get _numberOfMonths DateUtils.monthDelta(widget.firstDate, widget.lastDate) 1;void _vibrate() {switch (Theme.of(context).platform) {case TargetPlatform.android:case TargetPlatform.fuchsia:HapticFeedback.vibrate();break;case TargetPlatform.iOS:case TargetPlatform.linux:case TargetPlatform.macOS:case TargetPlatform.windows:break;}}// This updates the selected date range using this logic://// * From the unselected state, selecting one date creates the start date.// * If the next selection is before the start date, reset date range and// set the start date to that selection.// * If the next selection is on or after the start date, set the end date// to that selection.// * After both start and end dates are selected, any subsequent selection// resets the date range and sets start date to that selection.void _updateSelection(DateTime date) {_vibrate();setState(() {if (_startDate ! null _endDate null !date.isBefore(_startDate)) {_endDate date;widget.onEndDateChanged?.call(_endDate);} else {_startDate date;widget.onStartDateChanged?.call(_startDate);if (_endDate ! null) {_endDate null;widget.onEndDateChanged?.call(_endDate);}}});}Widget _buildMonthItem(BuildContext context, int index, bool beforeInitialMonth) {final int monthIndex beforeInitialMonth? _initialMonthIndex - index - 1: _initialMonthIndex index;final DateTime month DateUtils.addMonthsToMonthDate(widget.firstDate, monthIndex);return Stack(alignment: Alignment.center,children: [Text(${month.month},style: TextStyle(fontSize: 200,color: Colors.grey.withOpacity(0.1)),),_MonthItem(selectedDateStart: _startDate,selectedDateEnd: _endDate,currentDate: widget.currentDate,firstDate: widget.firstDate,lastDate: widget.lastDate,displayedMonth: month,onChanged: _updateSelection,)],);;}overrideWidget build(BuildContext context) {const Key sliverAfterKey Key(sliverAfterKey);return Column(children: Widget[_DayHeaders(),if (_showWeekBottomDivider) const Divider(height: 0),Expanded(child: _CalendarKeyboardNavigator(firstDate: widget.firstDate,lastDate: widget.lastDate,initialFocusedDay: _startDate ?? widget.initialStartDate ?? widget.currentDate,// In order to prevent performance issues when displaying the// correct initial month, 2 SliverLists are used to split the// months. The first item in the second SliverList is the initial// month to be displayed.child: CustomScrollView(key: _scrollViewKey,controller: _controller,center: sliverAfterKey,slivers: Widget[SliverList(delegate: SliverChildBuilderDelegate((BuildContext context, int index) _buildMonthItem(context, index, true),childCount: _initialMonthIndex,),),SliverList(key: sliverAfterKey,delegate: SliverChildBuilderDelegate((BuildContext context, int index) _buildMonthItem(context, index, false),childCount: _numberOfMonths - _initialMonthIndex,),),],),),),],);}
}class _CalendarKeyboardNavigator extends StatefulWidget {const _CalendarKeyboardNavigator({Key key,this.child,this.firstDate,this.lastDate,this.initialFocusedDay,}) : super(key: key);final Widget child;final DateTime firstDate;final DateTime lastDate;final DateTime initialFocusedDay;override_CalendarKeyboardNavigatorState createState() _CalendarKeyboardNavigatorState();
}class _CalendarKeyboardNavigatorState extends State_CalendarKeyboardNavigator {final MapShortcutActivator, Intent _shortcutMap const ShortcutActivator, Intent{SingleActivator(LogicalKeyboardKey.arrowLeft): DirectionalFocusIntent(TraversalDirection.left),SingleActivator(LogicalKeyboardKey.arrowRight): DirectionalFocusIntent(TraversalDirection.right),SingleActivator(LogicalKeyboardKey.arrowDown): DirectionalFocusIntent(TraversalDirection.down),SingleActivator(LogicalKeyboardKey.arrowUp): DirectionalFocusIntent(TraversalDirection.up),};MapType, ActionIntent _actionMap;FocusNode _dayGridFocus;TraversalDirection _dayTraversalDirection;DateTime _focusedDay;overridevoid initState() {super.initState();_actionMap Type, ActionIntent{NextFocusIntent: CallbackActionNextFocusIntent(onInvoke: _handleGridNextFocus),PreviousFocusIntent: CallbackActionPreviousFocusIntent(onInvoke: _handleGridPreviousFocus),DirectionalFocusIntent: CallbackActionDirectionalFocusIntent(onInvoke: _handleDirectionFocus),};_dayGridFocus FocusNode(debugLabel: Day Grid);}overridevoid dispose() {_dayGridFocus.dispose();super.dispose();}void _handleGridFocusChange(bool focused) {setState(() {if (focused) {_focusedDay ?? widget.initialFocusedDay;}});}/// Move focus to the next element after the day grid.void _handleGridNextFocus(NextFocusIntent intent) {_dayGridFocus.requestFocus();_dayGridFocus.nextFocus();}/// Move focus to the previous element before the day grid.void _handleGridPreviousFocus(PreviousFocusIntent intent) {_dayGridFocus.requestFocus();_dayGridFocus.previousFocus();}/// Move the internal focus date in the direction of the given intent.////// This will attempt to move the focused day to the next selectable day in/// the given direction. If the new date is not in the current month, then/// the page view will be scrolled to show the new dates month.////// For horizontal directions, it will move forward or backward a day (depending/// on the current [TextDirection]). For vertical directions it will move up and/// down a week at a time.void _handleDirectionFocus(DirectionalFocusIntent intent) {assert(_focusedDay ! null);setState(() {final DateTime nextDate _nextDateInDirection(_focusedDay, intent.direction);if (nextDate ! null) {_focusedDay nextDate;_dayTraversalDirection intent.direction;}});}static const MapTraversalDirection, int _directionOffset TraversalDirection, int{TraversalDirection.up: -DateTime.daysPerWeek,TraversalDirection.right: 1,TraversalDirection.down: DateTime.daysPerWeek,TraversalDirection.left: -1,};int _dayDirectionOffset(TraversalDirection traversalDirection, TextDirection textDirection) {// Swap left and right if the text direction if RTLif (textDirection TextDirection.rtl) {if (traversalDirection TraversalDirection.left)traversalDirection TraversalDirection.right;else if (traversalDirection TraversalDirection.right)traversalDirection TraversalDirection.left;}return _directionOffset[traversalDirection];}DateTime _nextDateInDirection(DateTime date, TraversalDirection direction) {final TextDirection textDirection Directionality.of(context);final DateTime nextDate DateUtils.addDaysToDate(date, _dayDirectionOffset(direction, textDirection));if (!nextDate.isBefore(widget.firstDate) !nextDate.isAfter(widget.lastDate)) {return nextDate;}return null;}overrideWidget build(BuildContext context) {return FocusableActionDetector(shortcuts: _shortcutMap,actions: _actionMap,focusNode: _dayGridFocus,onFocusChange: _handleGridFocusChange,child: _FocusedDate(date: _dayGridFocus.hasFocus ? _focusedDay : null,scrollDirection: _dayGridFocus.hasFocus ? _dayTraversalDirection : null,child: widget.child,),);}
}/// InheritedWidget indicating what the current focused date is for its children.
///
/// This is used by the [_MonthPicker] to let its children [_DayPicker]s know
/// what the currently focused date (if any) should be.
class _FocusedDate extends InheritedWidget {const _FocusedDate({Key key,Widget child,this.date,this.scrollDirection,}) : super(key: key, child: child);final DateTime date;final TraversalDirection scrollDirection;overridebool updateShouldNotify(_FocusedDate oldWidget) {return !DateUtils.isSameDay(date, oldWidget.date) || scrollDirection ! oldWidget.scrollDirection;}static _FocusedDate of(BuildContext context) {return context.dependOnInheritedWidgetOfExactType_FocusedDate();}
}class _DayHeaders extends StatelessWidget {/// Builds widgets showing abbreviated days of week. The first widget in the/// returned list corresponds to the first day of week for the current locale.////// Examples:////// /// ┌ Sunday is the first day of week in the US (en_US)/// |/// S M T W T F S -- the returned list contains these widgets/// _ _ _ _ _ 1 2/// 3 4 5 6 7 8 9////// ┌ But its Monday in the UK (en_GB)/// |/// M T W T F S S -- the returned list contains these widgets/// _ _ _ _ 1 2 3/// 4 5 6 7 8 9 10/// ListWidget _getDayHeaders(TextStyle headerStyle, MaterialLocalizations localizations) {final ListWidget result Widget[];for (int i localizations.firstDayOfWeekIndex; true; i (i 1) % 7) {final String weekday localizations.narrowWeekdays[i];result.add(ExcludeSemantics(child: Center(child: Text(weekday, style: headerStyle)),));if (i (localizations.firstDayOfWeekIndex - 1) % 7)break;}return result;}overrideWidget build(BuildContext context) {final ThemeData themeData Theme.of(context);final ColorScheme colorScheme themeData.colorScheme;final TextStyle textStyle themeData.textTheme.subtitle2.apply(color: colorScheme.onSurface);final MaterialLocalizations localizations MaterialLocalizations.of(context);final ListWidget labels _getDayHeaders(textStyle, localizations);// Add leading and trailing containers for edges of the custom grid layout.labels.insert(0, Container());labels.add(Container());return Container(constraints: BoxConstraints(maxWidth: MediaQuery.of(context).orientation Orientation.landscape? _maxCalendarWidthLandscape: _maxCalendarWidthPortrait,maxHeight: _monthItemRowHeight,),child: GridView.custom(shrinkWrap: true,gridDelegate: _monthItemGridDelegate,childrenDelegate: SliverChildListDelegate(labels,addRepaintBoundaries: false,),),);}
}class _MonthItemGridDelegate extends SliverGridDelegate {const _MonthItemGridDelegate();overrideSliverGridLayout getLayout(SliverConstraints constraints) {final double tileWidth (constraints.crossAxisExtent - 2 * _horizontalPadding) / DateTime.daysPerWeek;return _MonthSliverGridLayout(crossAxisCount: DateTime.daysPerWeek 2,dayChildWidth: tileWidth,edgeChildWidth: _horizontalPadding,reverseCrossAxis: axisDirectionIsReversed(constraints.crossAxisDirection),);}overridebool shouldRelayout(_MonthItemGridDelegate oldDelegate) false;
}const _MonthItemGridDelegate _monthItemGridDelegate _MonthItemGridDelegate();class _MonthSliverGridLayout extends SliverGridLayout {/// Creates a layout that uses equally sized and spaced tiles for each day of/// the week and an additional edge tile for padding at the start and end of/// each row.////// This is necessary to facilitate the painting of the range highlight/// correctly.const _MonthSliverGridLayout({this.crossAxisCount,this.dayChildWidth,this.edgeChildWidth,this.reverseCrossAxis,}) : assert(crossAxisCount ! null crossAxisCount 0),assert(dayChildWidth ! null dayChildWidth 0),assert(edgeChildWidth ! null edgeChildWidth 0),assert(reverseCrossAxis ! null);/// The number of children in the cross axis.final int crossAxisCount;/// The width in logical pixels of the day child widgets.final double dayChildWidth;/// The width in logical pixels of the edge child widgets.final double edgeChildWidth;/// Whether the children should be placed in the opposite order of increasing/// coordinates in the cross axis.////// For example, if the cross axis is horizontal, the children are placed from/// left to right when [reverseCrossAxis] is false and from right to left when/// [reverseCrossAxis] is true.////// Typically set to the return value of [axisDirectionIsReversed] applied to/// the [SliverConstraints.crossAxisDirection].final bool reverseCrossAxis;/// The number of logical pixels from the leading edge of one row to the/// leading edge of the next row.double get _rowHeight {return _monthItemRowHeight _monthItemSpaceBetweenRows;}/// The height in logical pixels of the children widgets.double get _childHeight {return _monthItemRowHeight;}overrideint getMinChildIndexForScrollOffset(double scrollOffset) {return crossAxisCount * (scrollOffset ~/ _rowHeight);}overrideint getMaxChildIndexForScrollOffset(double scrollOffset) {final int mainAxisCount (scrollOffset / _rowHeight).ceil();return math.max(0, crossAxisCount * mainAxisCount - 1);}double _getCrossAxisOffset(double crossAxisStart, bool isPadding) {if (reverseCrossAxis) {return((crossAxisCount - 2) * dayChildWidth 2 * edgeChildWidth) -crossAxisStart -(isPadding ? edgeChildWidth : dayChildWidth);}return crossAxisStart;}overrideSliverGridGeometry getGeometryForChildIndex(int index) {final int adjustedIndex index % crossAxisCount;final bool isEdge adjustedIndex 0 || adjustedIndex crossAxisCount - 1;final double crossAxisStart math.max(0, (adjustedIndex - 1) * dayChildWidth edgeChildWidth);return SliverGridGeometry(scrollOffset: (index ~/ crossAxisCount) * _rowHeight,crossAxisOffset: _getCrossAxisOffset(crossAxisStart, isEdge),mainAxisExtent: _childHeight,crossAxisExtent: isEdge ? edgeChildWidth : dayChildWidth,);}overridedouble computeMaxScrollOffset(int childCount) {assert(childCount 0);final int mainAxisCount ((childCount - 1) ~/ crossAxisCount) 1;final double mainAxisSpacing _rowHeight - _childHeight;return _rowHeight * mainAxisCount - mainAxisSpacing;}
}/// Displays the days of a given month and allows choosing a date range.
///
/// The days are arranged in a rectangular grid with one column for each day of
/// the week.
class _MonthItem extends StatefulWidget {/// Creates a month item._MonthItem({Key key,this.selectedDateStart,this.selectedDateEnd,this.currentDate,this.onChanged,this.firstDate,this.lastDate,this.displayedMonth,this.dragStartBehavior DragStartBehavior.start,}) : assert(firstDate ! null),assert(lastDate ! null),assert(!firstDate.isAfter(lastDate)),assert(selectedDateStart null || !selectedDateStart.isBefore(firstDate)),assert(selectedDateEnd null || !selectedDateEnd.isBefore(firstDate)),assert(selectedDateStart null || !selectedDateStart.isAfter(lastDate)),assert(selectedDateEnd null || !selectedDateEnd.isAfter(lastDate)),assert(selectedDateStart null || selectedDateEnd null || !selectedDateStart.isAfter(selectedDateEnd)),assert(currentDate ! null),assert(onChanged ! null),assert(displayedMonth ! null),assert(dragStartBehavior ! null),super(key: key);/// The currently selected start date.////// This date is highlighted in the picker.final DateTime selectedDateStart;/// The currently selected end date.////// This date is highlighted in the picker.final DateTime selectedDateEnd;/// The current date at the time the picker is displayed.final DateTime currentDate;/// Called when the user picks a day.final ValueChangedDateTime onChanged;/// The earliest date the user is permitted to pick.final DateTime firstDate;/// The latest date the user is permitted to pick.final DateTime lastDate;/// The month whose days are displayed by this picker.final DateTime displayedMonth;/// Determines the way that drag start behavior is handled.////// If set to [DragStartBehavior.start], the drag gesture used to scroll a/// date picker wheel will begin at the position where the drag gesture won/// the arena. If set to [DragStartBehavior.down] it will begin at the position/// where a down event is first detected.////// In general, setting this to [DragStartBehavior.start] will make drag/// animation smoother and setting it to [DragStartBehavior.down] will make/// drag behavior feel slightly more reactive.////// By default, the drag start behavior is [DragStartBehavior.start].////// See also:////// * [DragGestureRecognizer.dragStartBehavior], which gives an example for/// the different behaviors.final DragStartBehavior dragStartBehavior;override_MonthItemState createState() _MonthItemState();
}class _MonthItemState extends State_MonthItem {/// List of [FocusNode]s, one for each day of the month.ListFocusNode _dayFocusNodes;overridevoid initState() {super.initState();final int daysInMonth DateUtils.getDaysInMonth(widget.displayedMonth.year, widget.displayedMonth.month);_dayFocusNodes ListFocusNode.generate(daysInMonth,(int index) FocusNode(skipTraversal: true, debugLabel: Day ${index 1}),);}overridevoid didChangeDependencies() {super.didChangeDependencies();// Check to see if the focused date is in this month, if so focus it.final DateTime focusedDate _FocusedDate.of(context)?.date;if (focusedDate ! null DateUtils.isSameMonth(widget.displayedMonth, focusedDate)) {_dayFocusNodes[focusedDate.day - 1].requestFocus();}}overridevoid dispose() {for (final FocusNode node in _dayFocusNodes) {node.dispose();}super.dispose();}Color _highlightColor(BuildContext context) {return Theme.of(context).colorScheme.primary.withOpacity(0.12);}void _dayFocusChanged(bool focused) {if (focused) {final TraversalDirection focusDirection _FocusedDate.of(context)?.scrollDirection;if (focusDirection ! null) {ScrollPositionAlignmentPolicy policy ScrollPositionAlignmentPolicy.explicit;switch (focusDirection) {case TraversalDirection.up:case TraversalDirection.left:policy ScrollPositionAlignmentPolicy.keepVisibleAtStart;break;case TraversalDirection.right:case TraversalDirection.down:policy ScrollPositionAlignmentPolicy.keepVisibleAtEnd;break;}Scrollable.ensureVisible(primaryFocus.context,duration: _monthScrollDuration,alignmentPolicy: policy,);}}}Widget _buildDayItem(BuildContext context, DateTime dayToBuild, int firstDayOffset, int daysInMonth) {final ThemeData theme Theme.of(context);final ColorScheme colorScheme theme.colorScheme;final TextTheme textTheme theme.textTheme;final MaterialLocalizations localizations MaterialLocalizations.of(context);final TextDirection textDirection Directionality.of(context);final Color highlightColor _highlightColor(context);final int day dayToBuild.day;final bool isDisabled dayToBuild.isAfter(widget.lastDate) || dayToBuild.isBefore(widget.firstDate);BoxDecoration decoration;TextStyle itemStyle textTheme.bodyText2;final bool isRangeSelected widget.selectedDateStart ! null widget.selectedDateEnd ! null;final bool isSelectedDayStart widget.selectedDateStart ! null dayToBuild.isAtSameMomentAs(widget.selectedDateStart);final bool isSelectedDayEnd widget.selectedDateEnd ! null dayToBuild.isAtSameMomentAs(widget.selectedDateEnd);final bool isInRange isRangeSelected dayToBuild.isAfter(widget.selectedDateStart) dayToBuild.isBefore(widget.selectedDateEnd);_HighlightPainter highlightPainter;if (isSelectedDayStart || isSelectedDayEnd) {// The selected start and end dates gets a circle background// highlight, and a contrasting text color.itemStyle textTheme.bodyText2?.apply(color: colorScheme.onPrimary);decoration BoxDecoration(color: colorScheme.primary,shape: BoxShape.circle,);if (isRangeSelected widget.selectedDateStart ! widget.selectedDateEnd) {final _HighlightPainterStyle style isSelectedDayStart? _HighlightPainterStyle.highlightTrailing: _HighlightPainterStyle.highlightLeading;highlightPainter _HighlightPainter(color: highlightColor,style: style,textDirection: textDirection,);}} else if (isInRange) {// The days within the range get a light background highlight.highlightPainter _HighlightPainter(color: highlightColor,style: _HighlightPainterStyle.highlightAll,textDirection: textDirection,);} else if (isDisabled) {itemStyle textTheme.bodyText2?.apply(color: colorScheme.onSurface.withOpacity(0.38));} else if (DateUtils.isSameDay(widget.currentDate, dayToBuild)) {// The current day gets a different text color and a circle stroke// border.itemStyle textTheme.bodyText2?.apply(color: colorScheme.primary);decoration BoxDecoration(border: Border.all(color: colorScheme.primary),shape: BoxShape.circle,);}// We want the day of month to be spoken first irrespective of the// locale-specific preferences or TextDirection. This is because// an accessibility user is more likely to be interested in the// day of month before the rest of the date, as they are looking// for the day of month. To do that we prepend day of month to the// formatted full date.String semanticLabel ${localizations.formatDecimal(day)}, ${localizations.formatFullDate(dayToBuild)};if (isSelectedDayStart) {semanticLabel localizations.dateRangeStartDateSemanticLabel(semanticLabel);} else if (isSelectedDayEnd) {semanticLabel localizations.dateRangeEndDateSemanticLabel(semanticLabel);}Widget dayWidget Container(decoration: decoration,child: Center(child: Semantics(label: semanticLabel,selected: isSelectedDayStart || isSelectedDayEnd,child: ExcludeSemantics(child: Text(localizations.formatDecimal(day), style: itemStyle),),),),);if (highlightPainter ! null) {dayWidget CustomPaint(painter: highlightPainter,child: dayWidget,);}if (!isDisabled) {dayWidget InkResponse(focusNode: _dayFocusNodes[day - 1],onTap: () widget.onChanged(dayToBuild),radius: _monthItemRowHeight / 2 4,splashColor: colorScheme.primary.withOpacity(0.38),onFocusChange: _dayFocusChanged,child: dayWidget,);}return dayWidget;}Widget _buildEdgeContainer(BuildContext context, bool isHighlighted) {return Container(color: isHighlighted ? _highlightColor(context) : null);}overrideWidget build(BuildContext context) {final ThemeData themeData Theme.of(context);final TextTheme textTheme themeData.textTheme;final MaterialLocalizations localizations MaterialLocalizations.of(context);final int year widget.displayedMonth.year;final int month widget.displayedMonth.month;final int daysInMonth DateUtils.getDaysInMonth(year, month);final int dayOffset DateUtils.firstDayOffset(year, month, localizations);final int weeks ((daysInMonth dayOffset) / DateTime.daysPerWeek).ceil();final double gridHeight weeks * _monthItemRowHeight (weeks - 1) * _monthItemSpaceBetweenRows;final ListWidget dayItems Widget[];for (int i 0; true; i 1) {// 1-based day of month, e.g. 1-31 for January, and 1-29 for February on// a leap year.final int day i - dayOffset 1;if (day daysInMonth)break;if (day 1) {dayItems.add(Container());} else {final DateTime dayToBuild DateTime(year, month, day);final Widget dayItem _buildDayItem(context,dayToBuild,dayOffset,daysInMonth,);dayItems.add(dayItem);}}// Add the leading/trailing edge containers to each week in order to// correctly extend the range highlight.final ListWidget paddedDayItems Widget[];for (int i 0; i weeks; i) {final int start i * DateTime.daysPerWeek;final int end math.min(start DateTime.daysPerWeek,dayItems.length,);final ListWidget weekList dayItems.sublist(start, end);final DateTime dateAfterLeadingPadding DateTime(year, month, start - dayOffset 1);// Only color the edge container if it is after the start date and// on/before the end date.final bool isLeadingInRange !(dayOffset 0 i 0) widget.selectedDateStart ! null widget.selectedDateEnd ! null dateAfterLeadingPadding.isAfter(widget.selectedDateStart) !dateAfterLeadingPadding.isAfter(widget.selectedDateEnd);weekList.insert(0, _buildEdgeContainer(context, isLeadingInRange));// Only add a trailing edge container if it is for a full week and not a// partial week.if (end dayItems.length || (end dayItems.length dayItems.length % DateTime.daysPerWeek 0)) {final DateTime dateBeforeTrailingPadding DateTime(year, month, end - dayOffset);// Only color the edge container if it is on/after the start date and// before the end date.final bool isTrailingInRange widget.selectedDateStart ! null widget.selectedDateEnd ! null !dateBeforeTrailingPadding.isBefore(widget.selectedDateStart) dateBeforeTrailingPadding.isBefore(widget.selectedDateEnd);weekList.add(_buildEdgeContainer(context, isTrailingInRange));}paddedDayItems.addAll(weekList);}final double maxWidth MediaQuery.of(context).orientation Orientation.landscape? _maxCalendarWidthLandscape: _maxCalendarWidthPortrait;return Column(children: Widget[Container(constraints: BoxConstraints(maxWidth: maxWidth),height: _monthItemHeaderHeight,padding: const EdgeInsets.symmetric(horizontal: 16),alignment: AlignmentDirectional.centerStart,child: ExcludeSemantics(child: Text(localizations.formatMonthYear(widget.displayedMonth),style: textTheme.bodyText2.apply(color: themeData.colorScheme.onSurface),),),),Container(constraints: BoxConstraints(maxWidth: maxWidth,maxHeight: gridHeight,),child: GridView.custom(physics: const NeverScrollableScrollPhysics(),gridDelegate: _monthItemGridDelegate,childrenDelegate: SliverChildListDelegate(paddedDayItems,addRepaintBoundaries: false,),),),const SizedBox(height: _monthItemFooterHeight),],);}
}/// Determines which style to use to paint the highlight.
enum _HighlightPainterStyle {/// Paints nothing.none,/// Paints a rectangle that occupies the leading half of the space.highlightLeading,/// Paints a rectangle that occupies the trailing half of the space.highlightTrailing,/// Paints a rectangle that occupies all available space.highlightAll,
}/// This custom painter will add a background highlight to its child.
///
/// This highlight will be drawn depending on the [style], [color], and
/// [textDirection] supplied. It will either paint a rectangle on the
/// left/right, a full rectangle, or nothing at all. This logic is determined by
/// a combination of the [style] and [textDirection].
class _HighlightPainter extends CustomPainter {_HighlightPainter({this.color,this.style _HighlightPainterStyle.none,this.textDirection,});final Color color;final _HighlightPainterStyle style;final TextDirection textDirection;overridevoid paint(Canvas canvas, Size size) {if (style _HighlightPainterStyle.none) {return;}final Paint paint Paint()..color color..style PaintingStyle.fill;final Rect rectLeft Rect.fromLTWH(0, 0, size.width / 2, size.height);final Rect rectRight Rect.fromLTWH(size.width / 2, 0, size.width / 2, size.height);switch (style) {case _HighlightPainterStyle.highlightTrailing:canvas.drawRect(textDirection TextDirection.ltr ? rectRight : rectLeft,paint,);break;case _HighlightPainterStyle.highlightLeading:canvas.drawRect(textDirection TextDirection.ltr ? rectLeft : rectRight,paint,);break;case _HighlightPainterStyle.highlightAll:canvas.drawRect(Rect.fromLTWH(0, 0, size.width, size.height),paint,);break;case _HighlightPainterStyle.none:break;}}overridebool shouldRepaint(CustomPainter oldDelegate) false;
}class _InputDateRangePickerDialog extends StatelessWidget {const _InputDateRangePickerDialog({Key key,this.selectedStartDate,this.selectedEndDate,this.currentDate,this.picker,this.onConfirm,this.onCancel,this.confirmText,this.cancelText,this.helpText,this.entryModeButton,}) : super(key: key);final DateTime selectedStartDate;final DateTime selectedEndDate;final DateTime currentDate;final Widget picker;final VoidCallback onConfirm;final VoidCallback onCancel;final String confirmText;final String cancelText;final String helpText;final Widget entryModeButton;String _formatDateRange(BuildContext context, DateTime start, DateTime end, DateTime now) {final MaterialLocalizations localizations MaterialLocalizations.of(context);final String startText _formatRangeStartDate(localizations, start, end);final String endText _formatRangeEndDate(localizations, start, end, now);if (start null || end null) {return localizations.unspecifiedDateRange;}if (Directionality.of(context) TextDirection.ltr) {return $startText – $endText;} else {return $endText – $startText;}}overrideWidget build(BuildContext context) {final ThemeData theme Theme.of(context);final ColorScheme colorScheme theme.colorScheme;final MaterialLocalizations localizations MaterialLocalizations.of(context);final Orientation orientation MediaQuery.of(context).orientation;final TextTheme textTheme theme.textTheme;final Color onPrimarySurfaceColor colorScheme.brightness Brightness.light? colorScheme.onPrimary: colorScheme.onSurface;final TextStyle dateStyle orientation Orientation.landscape? textTheme.headline5?.apply(color: onPrimarySurfaceColor): textTheme.headline4?.apply(color: onPrimarySurfaceColor);final String dateText _formatDateRange(context, selectedStartDate, selectedEndDate, currentDate);final String semanticDateText selectedStartDate ! null selectedEndDate ! null? ${localizations.formatMediumDate(selectedStartDate)} – ${localizations.formatMediumDate(selectedEndDate)}: ;final Widget header _DatePickerHeader(helpText: helpText ?? localizations.dateRangePickerHelpText,titleText: dateText,titleSemanticsLabel: semanticDateText,titleStyle: dateStyle,orientation: orientation,isShort: orientation Orientation.landscape,entryModeButton: entryModeButton,);final Widget actions Container(alignment: AlignmentDirectional.centerEnd,constraints: const BoxConstraints(minHeight: 52.0),padding: const EdgeInsets.symmetric(horizontal: 8),child: OverflowBar(spacing: 8,children: Widget[TextButton(onPressed: onCancel,child: Text(cancelText ?? localizations.cancelButtonLabel),),TextButton(onPressed: onConfirm,child: Text(confirmText ?? localizations.okButtonLabel),),],),);switch (orientation) {case Orientation.portrait:return Column(mainAxisSize: MainAxisSize.min,crossAxisAlignment: CrossAxisAlignment.stretch,children: Widget[header,Expanded(child: picker),actions,],);case Orientation.landscape:return Row(mainAxisSize: MainAxisSize.min,crossAxisAlignment: CrossAxisAlignment.stretch,children: Widget[header,Flexible(child: Column(mainAxisSize: MainAxisSize.min,crossAxisAlignment: CrossAxisAlignment.stretch,children: Widget[Expanded(child: picker),actions,],),),],);}}
}/// Provides a pair of text fields that allow the user to enter the start and
/// end dates that represent a range of dates.
class _InputDateRangePicker extends StatefulWidget {/// Creates a row with two text fields configured to accept the start and end dates/// of a date range._InputDateRangePicker({Key key,DateTime initialStartDate,DateTime initialEndDate,DateTime firstDate,DateTime lastDate,this.onStartDateChanged,this.onEndDateChanged,this.helpText,this.errorFormatText,this.errorInvalidText,this.errorInvalidRangeText,this.fieldStartHintText,this.fieldEndHintText,this.fieldStartLabelText,this.fieldEndLabelText,this.autofocus false,this.autovalidate false,}) : initialStartDate initialStartDate null ? null : DateUtils.dateOnly(initialStartDate),initialEndDate initialEndDate null ? null : DateUtils.dateOnly(initialEndDate),assert(firstDate ! null),firstDate DateUtils.dateOnly(firstDate),assert(lastDate ! null),lastDate DateUtils.dateOnly(lastDate),assert(firstDate ! null),assert(lastDate ! null),assert(autofocus ! null),assert(autovalidate ! null),super(key: key);/// The [DateTime] that represents the start of the initial date range selection.final DateTime initialStartDate;/// The [DateTime] that represents the end of the initial date range selection.final DateTime initialEndDate;/// The earliest allowable [DateTime] that the user can select.final DateTime firstDate;/// The latest allowable [DateTime] that the user can select.final DateTime lastDate;/// Called when the user changes the start date of the selected range.final ValueChangedDateTime onStartDateChanged;/// Called when the user changes the end date of the selected range.final ValueChangedDateTime onEndDateChanged;/// The text that is displayed at the top of the header.////// This is used to indicate to the user what they are selecting a date for.final String helpText;/// Error text used to indicate the text in a field is not a valid date.final String errorFormatText;/// Error text used to indicate the date in a field is not in the valid range/// of [firstDate] - [lastDate].final String errorInvalidText;/// Error text used to indicate the dates given dont form a valid date/// range (i.e. the start date is after the end date).final String errorInvalidRangeText;/// Hint text shown when the start date field is empty.final String fieldStartHintText;/// Hint text shown when the end date field is empty.final String fieldEndHintText;/// Label used for the start date field.final String fieldStartLabelText;/// Label used for the end date field.final String fieldEndLabelText;/// {macro flutter.widgets.editableText.autofocus}final bool autofocus;/// If true, this the date fields will validate and update their error text/// immediately after every change. Otherwise, you must call/// [_InputDateRangePickerState.validate] to validate.final bool autovalidate;override_InputDateRangePickerState createState() _InputDateRangePickerState();
}/// The current state of an [_InputDateRangePicker]. Can be used to
/// [validate] the date field entries.
class _InputDateRangePickerState extends State_InputDateRangePicker {String _startInputText;String _endInputText;DateTime _startDate;DateTime _endDate;TextEditingController _startController;TextEditingController _endController;String _startErrorText;String _endErrorText;bool _autoSelected false;overridevoid initState() {super.initState();_startDate widget.initialStartDate;_startController TextEditingController();_endDate widget.initialEndDate;_endController TextEditingController();}overridevoid dispose() {_startController.dispose();_endController.dispose();super.dispose();}overridevoid didChangeDependencies() {super.didChangeDependencies();final MaterialLocalizations localizations MaterialLocalizations.of(context);if (_startDate ! null) {_startInputText localizations.formatCompactDate(_startDate);final bool selectText widget.autofocus !_autoSelected;_updateController(_startController, _startInputText, selectText);_autoSelected selectText;}if (_endDate ! null) {_endInputText localizations.formatCompactDate(_endDate);_updateController(_endController, _endInputText, false);}}/// Validates that the text in the start and end fields represent a valid/// date range.////// Will return true if the range is valid. If not, it will/// return false and display an appropriate error message under one of the/// text fields.bool validate() {String startError _validateDate(_startDate);final String endError _validateDate(_endDate);if (startError null endError null) {if (_startDate.isAfter(_endDate)) {startError widget.errorInvalidRangeText ?? MaterialLocalizations.of(context).invalidDateRangeLabel;}}setState(() {_startErrorText startError;_endErrorText endError;});return startError null endError null;}DateTime _parseDate(String text) {final MaterialLocalizations localizations MaterialLocalizations.of(context);return localizations.parseCompactDate(text);}String _validateDate(DateTime date) {if (date null) {return widget.errorFormatText ?? MaterialLocalizations.of(context).invalidDateFormatLabel;} else if (date.isBefore(widget.firstDate) || date.isAfter(widget.lastDate)) {return widget.errorInvalidText ?? MaterialLocalizations.of(context).dateOutOfRangeLabel;}return null;}void _updateController(TextEditingController controller, String text, bool selectText) {TextEditingValue textEditingValue controller.value.copyWith(text: text);if (selectText) {textEditingValue textEditingValue.copyWith(selection: TextSelection(baseOffset: 0,extentOffset: text.length,));}controller.value textEditingValue;}void _handleStartChanged(String text) {setState(() {_startInputText text;_startDate _parseDate(text);widget.onStartDateChanged?.call(_startDate);});if (widget.autovalidate) {validate();}}void _handleEndChanged(String text) {setState(() {_endInputText text;_endDate _parseDate(text);widget.onEndDateChanged?.call(_endDate);});if (widget.autovalidate) {validate();}}overrideWidget build(BuildContext context) {final MaterialLocalizations localizations MaterialLocalizations.of(context);final InputDecorationTheme inputTheme Theme.of(context).inputDecorationTheme;return Row(crossAxisAlignment: CrossAxisAlignment.start,children: Widget[Expanded(child: TextField(controller: _startController,decoration: InputDecoration(border: inputTheme.border ?? const UnderlineInputBorder(),filled: inputTheme.filled,hintText: widget.fieldStartHintText ?? localizations.dateHelpText,labelText: widget.fieldStartLabelText ?? localizations.dateRangeStartLabel,errorText: _startErrorText,),keyboardType: TextInputType.datetime,onChanged: _handleStartChanged,autofocus: widget.autofocus,),),const SizedBox(width: 8),Expanded(child: TextField(controller: _endController,decoration: InputDecoration(border: inputTheme.border ?? const UnderlineInputBorder(),filled: inputTheme.filled,hintText: widget.fieldEndHintText ?? localizations.dateHelpText,labelText: widget.fieldEndLabelText ?? localizations.dateRangeEndLabel,errorText: _endErrorText,),keyboardType: TextInputType.datetime,onChanged: _handleEndChanged,),),],);}
}
引用
_showRangeDatePickerForDay() async {final DateTimeRange _picker await showDateRangePickerA(context: context, // 上下文// firstDate: DateTime(time.year, time.month - 1, 1), // 开始日期firstDate: DateTime(2024, 5, 31), // 开始日期lastDate: DateTime(time.year 1, 12, 30), // 结束日期currentDate: DateTime.now(), // 当前日期initialDateRange: DateTimeRange(start: DateTime.now().subtract(Duration(days: 5)),end: DateTime.now().add(Duration(days: 5))), // 初始时间范围initialEntryMode: DatePickerEntryMode.calendarOnly, // DatePickerEntryMode 日历弹框样式 calendar: 默认显示日历可切换成输入模式input:默认显示输入模式可切换到日历calendarOnly:只显示日历inputOnly:只显示输入模式helpText: 请选择日期区间, // 左上角提示语cancelText: 取消, // 取消按钮 文案confirmText: 确定, // 确认按钮 文案saveText: 完成, // 保存按钮 文案errorFormatText: 输入格式有误, // 格式错误时下方提示errorInvalidRangeText: 开始日期不可以在结束日期之后, // 输入日期范围不合法 开始日期在结束日期之后errorInvalidText: 输入不合法, // 输入了不在 first 与 last 之间的日期提示语fieldStartHintText: 请输入开始日期, // 开始日期 输入框默认提示语fieldEndHintText: 请输入结束日期, // 结束日期 输入框默认提示语fieldStartLabelText: 开始日期, // 开始日期 输入框上方提示语fieldEndLabelText: 结束日期, // 结束日期 输入框上方提示语useRootNavigator: true, // 是否使用根导航默认为 true官方文档也没做详解暂时没用到textDirection: TextDirection.ltr, // 水平方向 显示方向 默认 ltr);print(start:${_picker.start} end:${_picker.end});}
