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实际业务中经常需要展示某个网站, 并且希望在展示的时候单击网站可直接访问, 本节演示在表格中如何添加超链接支持.
需求
假设我需要渲染一个Study类, 它只有三个属性id,name和website, 其中id只支持展示, name只支持编辑, 而website只支持单击时跳转到相应的网站, 效果…背景
实际业务中经常需要展示某个网站, 并且希望在展示的时候单击网站可直接访问, 本节演示在表格中如何添加超链接支持.
需求
假设我需要渲染一个Study类, 它只有三个属性id,name和website, 其中id只支持展示, name只支持编辑, 而website只支持单击时跳转到相应的网站, 效果图如下:
方案
要在表格中添加超链接支持, 需要特殊的CellLableProvider, Jface提供了ColumnLabelProvider, 要想实现超链接, 只需要重新实现其中的update和getText方法.
方法名方法签名功能描述getTextString getText(Object element)提供表格渲染后展示的文本的内容updatevoid update(ViewerCell cell)提供表格对象的额外展示项, 比如背景颜色, 字体的设置等等
我们的超链接支持就可以放在update中来进行扩展实现:
创建Link对象, 并通过TableEditor将其与TableItem关联起来添加Link对象的单击事件监听, 点击时进行跳转
Link link new Link((Composite) cell.getControl(), SWT.NONE);
link.setText(a study.website /a);
TableItem item (TableItem) cell.getItem();
TableEditor editor new TableEditor(item.getParent());
editor.grabHorizontal true;
editor.grabVertical true;
editor.setEditor(link, item, cell.getColumnIndex());
editor.layout();
link.addListener(SWT.Selection, e - {try {Desktop.getDesktop().browse(new URI(study.website));} catch (IOException | URISyntaxException ex) {throw new RuntimeException(ex);}
});注意实现
之前我们设置CellLabelProvider时是通过Tabel级别的对象进行的, 实际上我们往往是根据不同的Column来设置更为个性化的展示的, 因此, 在创建Column的同时设置CellLableProvider更为合理. 伪代码:
TableViewer tableViewer ...;
Table table tableViewer.getTable();
TableColumn tableColumn TableColumnFactory.newTableColumn(SWT.NONE)....create(table);
TableViewerColumn tableViewerColumn new TableViewerColumn(tableViewer, tableColumn);
// 每一列设置一个特定的cellLabelProvider
tableViewerColumn.setLabelProvider(cellLabelProvider);源码
import org.eclipse.jface.viewers.*;
import org.eclipse.jface.widgets.TableColumnFactory;
import org.eclipse.swt.SWT;
import org.eclipse.swt.custom.TableEditor;
import org.eclipse.swt.layout.FillLayout;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.*;import java.awt.*;
import java.io.IOException;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.net.URI;
import java.net.URISyntaxException;
import java.util.Optional;public class Study {Column(value ID, labelProviderClass StudyLabelProvider.class)public int id;Column(value 名称, labelProviderClass StudyLabelProvider.class, width 200)TextEditorpublic String name;Column(value 网站, labelProviderClass StudyLabelProvider.class, width 300)public String website;public Study(int id, String name, String website) {this.id id;this.name name;this.website website;}private static Study[] studies() {return new Study[]{new Study(1, github, https://github.com), new Study(2, 死磕Java, https://skjava.com)};}public static void main(String[] args) throws InvocationTargetException, InstantiationException, IllegalAccessException, NoSuchMethodException {Display display new Display();Shell shell new Shell(display);shell.setLayout(new FillLayout());var tableViewer new TableViewer(shell, SWT.MULTI | SWT.FULL_SELECTION | SWT.BORDER | SWT.V_SCROLL | SWT.H_SCROLL);Table table tableViewer.getTable();table.setHeaderVisible(true);table.setLinesVisible(true);Field[] fields Study.class.getFields();for (Field field : fields) {Column column field.getAnnotation(Column.class);String columnText column.value();Class? extends CellLabelProvider labelProviderClass column.labelProviderClass();CellLabelProvider cellLabelProvider;if (!(CellLabelProvider.class labelProviderClass)) {Constructor? extends CellLabelProvider constructor labelProviderClass.getConstructor(String.class);cellLabelProvider constructor.newInstance(columnText);} else {cellLabelProvider new StudyLabelProvider(columnText);}TableColumn tableColumn TableColumnFactory.newTableColumn(SWT.NONE).width(column.width()).text(columnText).align(SWT.CENTER).create(table);TableViewerColumn tableViewerColumn new TableViewerColumn(tableViewer, tableColumn);tableViewerColumn.setLabelProvider(cellLabelProvider);EditingSupport editingSupport null;TextEditor textEditor field.getAnnotation(TextEditor.class);if (textEditor ! null) {Class? extends EditingSupport editingSupportClass textEditor.editingSupportClass();Constructor? extends EditingSupport constructor editingSupportClass.getConstructor(TableViewerColumn.class);editingSupport constructor.newInstance(tableViewerColumn);}Optional.ofNullable(editingSupport).ifPresent(tableViewerColumn::setEditingSupport);}ColumnViewerEditorActivationStrategy activationStrategy new ColumnViewerEditorActivationStrategy(tableViewer) {Overrideprotected boolean isEditorActivationEvent(ColumnViewerEditorActivationEvent event) {// 只有双击事件才激活编辑器return event.eventType ColumnViewerEditorActivationEvent.MOUSE_DOUBLE_CLICK_SELECTION || event.eventType ColumnViewerEditorActivationEvent.PROGRAMMATIC || event.eventType ColumnViewerEditorActivationEvent.TRAVERSAL;}};table.setHeaderBackground(display.getSystemColor(SWT.COLOR_TITLE_BACKGROUND));table.setHeaderForeground(display.getSystemColor(SWT.COLOR_TITLE_FOREGROUND));TableViewerFocusCellManager focusCellManager new TableViewerFocusCellManager(tableViewer, new FocusCellOwnerDrawHighlighter(tableViewer));TableViewerEditor.create(tableViewer, focusCellManager, activationStrategy, ColumnViewerEditor.DEFAULT);tableViewer.setContentProvider(ArrayContentProvider.getInstance());tableViewer.setInput(Study.studies());shell.open();while (!shell.isDisposed()) {if (!display.readAndDispatch()) {display.sleep();}}}public static class StudyEditingSupport extends EditingSupport {private final TableViewerColumn tableViewerColumn;private final String title;public StudyEditingSupport(TableViewerColumn tableViewerColumn) {super(tableViewerColumn.getViewer());this.tableViewerColumn tableViewerColumn;TableColumn tableColumn tableViewerColumn.getColumn();this.title tableColumn.getText();}Overrideprotected CellEditor getCellEditor(Object o) {return new TextCellEditor(tableViewerColumn.getColumn().getParent());}Overrideprotected boolean canEdit(Object o) {return true;}Overrideprotected Object getValue(Object o) {if (!(o instanceof Study study)) {return ;}return switch (title) {case 名称 - study.name;default - study.website;};}Overrideprotected void setValue(Object o, Object o1) {if (!(o instanceof Study study)) {return;}switch (title) {case 名称 - study.name String.valueOf(o1);default - study.website String.valueOf(o1);}getViewer().refresh(o);}}public static class StudyLabelProvider extends ColumnLabelProvider {private final String title;public StudyLabelProvider(String title) {super();this.title title;}Overridepublic void update(ViewerCell cell) {if (!(cell.getElement() instanceof Study study)) {return;}var text switch (title) {case ID - String.valueOf(study.id);case 名称 - study.name;default - {Link link new Link((Composite) cell.getControl(), SWT.NONE);link.setText(a study.website /a);TableItem item (TableItem) cell.getItem();TableEditor editor new TableEditor(item.getParent());editor.grabHorizontal true;editor.grabVertical true;editor.setEditor(link, item, cell.getColumnIndex());editor.layout();link.addListener(SWT.Selection, e - {try {Desktop.getDesktop().browse(new URI(study.website));} catch (IOException | URISyntaxException ex) {throw new RuntimeException(ex);}});yield ;}};cell.setText(text);}Overridepublic String getText(Object element) {if (!(element instanceof Study study)) {return ;}return switch (title) {case ID - String.valueOf(study.id);case 名称 - study.name;default - study.website;};}}Retention(RetentionPolicy.RUNTIME)Target(ElementType.FIELD)public interface Column {String value();Class? extends CellLabelProvider labelProviderClass() default CellLabelProvider.class;int width() default 100;}Retention(RetentionPolicy.RUNTIME)Target(ElementType.FIELD)public interface TextEditor {Class? extends EditingSupport editingSupportClass() default StudyEditingSupport.class;}
}
