Android RecyclerView详解及简单实例

package com.example.osserver.recycler;import android.app.Activity;import android.os.Bundle;import android.support.v7.app.ActionBarActivity;import android.support.v7.widget.*;import android.support.v7.widget.LinearLayoutManager;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;import android.widget.TextView;import java.util.ArrayList;import java.util.List;public class MainActivity extends ActionBarActivity {  private RecyclerView mRecyclerView;  private List<String> mDatas;  private HomeAdapter mAdapter;  @Override  protected void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    setContentView(R.layout.activity_main);    initData();    mRecyclerView = (RecyclerView)findViewById(R.id.id_recyclerview);    mRecyclerView.setLayoutManager(new LinearLayoutManager(this));    mRecyclerView.setAdapter(mAdapter = new HomeAdapter());    mRecyclerView.addItemDecoration(new DividerItemDecoration(this,DividerItemDecoration.HORIZONTAL_LIST));  }  private void initData() {        mDatas = new ArrayList<String>();        for (int i ='A';i<='Z';i++){          mDatas.add(""+(char)i);    }  }class HomeAdapter extends RecyclerView.Adapter<MyViewHolder>{  @Override  public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {    MyViewHolder holder = new MyViewHolder(LayoutInflater.from(MainActivity.this).inflate(R.layout.item,parent,false));    return holder;  }  @Override  public void onBindViewHolder(MyViewHolder holder, int position) {    holder.tv.setText(mDatas.get(position));  }  @Override  public int getItemCount() {    return mDatas.size();  }}  class MyViewHolder extends RecyclerView.ViewHolder  {    TextView tv;    public MyViewHolder(View view) {      super(view);      tv = (TextView)view.findViewById(R.id.id_num);    }  }}

package com.zhy.sample.demo_recyclerview;/* * Copyright (C) 2014 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * limitations under the License. */import android.content.Context;import android.content.res.TypedArray;import android.graphics.Canvas;import android.graphics.Rect;import android.graphics.drawable.Drawable;import android.support.v7.widget.LinearLayoutManager;import android.support.v7.widget.RecyclerView;import android.support.v7.widget.RecyclerView.State;import android.util.Log;import android.view.View;/** * This class is from the v7 samples of the Android SDK. It's not by me! * <p/> * See the license above for details. */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;  }  @Override  public void onDraw(Canvas c, RecyclerView parent) {    Log.v("recyclerview - itemdecoration", "onDraw()");    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);      android.support.v7.widget.RecyclerView v = new android.support.v7.widget.RecyclerView(parent.getContext());      final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child          .getLayoutParams();      final int top = child.getBottom() + params.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);    }  }  @Override  public void getItemOffsets(Rect outRect, int itemPosition, RecyclerView parent) {    if (mOrientation == VERTICAL_LIST) {      outRect.set(0, 0, 0, mDivider.getIntrinsicHeight());    } else {      outRect.set(0, 0, mDivider.getIntrinsicWidth(), 0);    }  }}