网站开发有名的公司,适合大学生做的网站有哪些,手机网站与PC网站,网站建设广州公司哪家好关于RecyclerView大家都不陌生了#xff0c;它的使用也越来越受欢迎#xff0c;现在总体了解一下RecyclerView的作用#xff0c;为什么会有RecyclerView呢#xff0c;我用ListView也能干所有的事情啊#xff0c;尺有所短#xff0c;寸有所长#xff0c;先来看看Recycler…关于RecyclerView大家都不陌生了它的使用也越来越受欢迎现在总体了解一下RecyclerView的作用为什么会有RecyclerView呢我用ListView也能干所有的事情啊尺有所短寸有所长先来看看RecyclerView的优点吧可以快速实现gallery 效果。可以快速实现瀑布流效果。可以方便地为Item添加动画效果。
好吧看到这些对RecyclerView的强大应该有一些认识了吧再看看使用RecyclerView会遇到哪些麻烦
1. 没有为Item提供点击事件。
2. 没有为Item提供分割线。先来实现一个简单的RecyclerView–
在grade里引入support包
compile com.android.support:appcompat-v7:23.3.0
compile com.android.support:recyclerview-v7:MainActivity
public class MainActivity extends AppCompatActivity {private RecyclerView mRecyclerView;private ListString mListData;Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);initData();mRecyclerView (RecyclerView) findViewById(R.id.rl_list);mRecyclerView.setLayoutManager(new LinearLayoutManager(this));mRecyclerView.setAdapter(new RecyclerAdapter(this,mListData));}private void initData() {mListData new ArrayListString();for (int i 0; i 100; i) {mListData.add(我是第 i 行);}}}RecyclerAdapter
public class RecyclerAdapter extends RecyclerView.AdapterRecyclerAdapter.TestViewHolder {private Context mContext;private ListString mList;public RecyclerAdapter(Context context, ListString list) {mContext context;mList list;}Overridepublic TestViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {TestViewHolder holder new TestViewHolder(LayoutInflater.from(mContext).inflate(R.layout.recyclerview_item_layout, parent, false));return holder;}Overridepublic void onBindViewHolder(TestViewHolder holder, int position) {holder.tv.setText(mList.get(position));}Overridepublic int getItemCount() {return mList.size();}class TestViewHolder extends RecyclerView.ViewHolder {
; TextView tv;public TestViewHolder(View view) {super(view);tv (TextView) view.findViewById(R.id.tv_number);}}
}
activity_main.xml
?xml version1.0 encodingutf-8?
RelativeLayout xmlns:androidhttp://schemas.android.com/apk/res/androidxmlns:toolshttp://schemas.android.com/toolsandroid:layout_widthmatch_parentandroid:layout_heightmatch_parentandroid:paddingBottomdimen/activity_vertical_marginandroid:paddingLeftdimen/activity_horizontal_marginandroid:paddingRightdimen/activity_horizontal_marginandroid:paddingTopdimen/activity_vertical_margintools:contextcom.farmlink.myrecyclerview.MainActivityandroid.support.v7.widget.RecyclerViewandroid:layout_widthmatch_parentandroid:layout_heightmatch_parentandroid:idid/rl_list /
/RelativeLayout
看一下效果图
没有分割线很糟糕不过RecycleView 给你提供了绘制分割线的方法
public class DividerItemDecoration extends RecyclerView.ItemDecoration {private static final int[] ATTRS new int[]{android.R.attr.listDivider};public static final int HORIZONTAL_LIST LinearLayoutManager.HORIZONTAL;public static final int VERTICAL_LIST LinearLayoutManager.VERTICAL;private Drawable mDivider;private int mOrientation;public DividerItemDecoration(Context context, int orientation) {final TypedArray a context.obtainStyledAttributes(ATTRS);mDivider a.getDrawable(0);a.recycle();setOrientation(orientation);}public void setOrientation(int orientation) {if (orientation ! HORIZONTAL_LIST orientation ! VERTICAL_LIST) {throw new IllegalArgumentException(invalid orientation);}mOrientation orientation;}Overridepublic void onDrawOver(Canvas c, RecyclerView parent, RecyclerView.State state) {super.onDrawOver(c, parent, state);if (mOrientation VERTICAL_LIST) {drawVertical(c, parent);} else {drawHorizontal(c, parent);}}public void drawVertical(Canvas c, RecyclerView parent) {final int left parent.getPaddingLeft();final int right parent.getWidth() - parent.getPaddingRight();final int childCount parent.getChildCount();for (int i 0; i childCount; i ) {final View child parent.getChildAt(i);final RecyclerView.LayoutParams layoutParams (RecyclerView.LayoutParams)child.getLayoutParams();final int top child.getBottom() layoutParams.bottomMargin;final int bottom top mDivider.getIntrinsicHeight();mDivider.setBounds(left, top, right, bottom);mDivider.draw(c);}}public void drawHorizontal(Canvas c, RecyclerView parent) {final int top parent.getPaddingTop();final int bottom parent.getHeight() - parent.getPaddingBottom();final int childCount parent.getChildCount();for (int i 0; i childCount; i) {final View child parent.getChildAt(i);final RecyclerView.LayoutParams params (RecyclerView.LayoutParams) child.getLayoutParams();final int left child.getRight() params.rightMargin;final int right left mDivider.getIntrinsicHeight();mDivider.setBounds(left, top, right, bottom);mDivider.draw(c);}}Overridepublic void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {super.getItemOffsets(outRect, view, parent, state);if (mOrientation VERTICAL_LIST) {outRect.set(0, 0, 0, mDivider.getIntrinsicHeight());} else {outRect.set(0, 0, mDivider.getIntrinsicWidth(), 0);}}
}
加上这句就ok了
mRecyclerView.addItemDecoration(new DividerItemDecoration(this, LinearLayoutManager.VERTICAL));关于RecyclerView 先了解到这里。
