RecyclerView
控件简介
- ListView的升级版
- LinearLayoutManager
- GridLayoutManager
- StaggeredGridLayoutManager
- 定制Item动画，指定Item之间的分隔线
RecyclerView相关的重要类
- Adapter
- ViewHolder
- LayoutManager
- ItemDecoration
- ItemAnimator
添加RecyclerView控件依赖包
Android Studio开发工具，在本项目的build.gradle文件中添加
compile 'com.android.support:recyclerview-v7:23.1.1'
如果是eclipse的话，下载jar包，放到lib下，一般都会自动的build path,检查下即可。
如何下载jar ?
在SDK Manager中下载Support Library
sdk\extras\android\support\v7\recyclerview\libs
为Recycler准备数据
package demo.turing.com.materialdesignwidget.recyclerView; import java.util.ArrayList; import demo.turing.com.materialdesignwidget.recyclerView.model.SampleModel; /** * MyApp * * @author Mr.Yang on 2016-03-30 20:21. * @version 1.0 * @desc */ public class SimulatorData { public static ArrayList<SampleModel> getSampleModelData(int size) { ArrayList<SampleModel> sampleData = new ArrayList<SampleModel>(size); for (int i = 0; i < size; i++) { sampleData.add(new SampleModel("新的列表项< " + i + " >")); } return sampleData; } }
package demo.turing.com.materialdesignwidget.recyclerView.model; /** * MyApp * * @author Mr.Yang on 2016-03-30 20:23. * @version 1.0 * 对应Item中药显示的数据项 */ public class SampleModel { private String text; public SampleModel(String text) { this.text = text; } public String getText() { return text; } public void setText(String text) { this.text = text; } }
绘制列表项之间的分隔线
package demo.turing.com.materialdesignwidget.recyclerView; 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.view.View; /** * MyApp * * @author Mr.Yang on 2016-03-30 20:37. * @version 1.0 * 分隔条 * * * DividerItemDecoration https://gist.github.com/alexfu/0f464fc3742f134ccd1e */ public class DividerItemDecoration extends RecyclerView.ItemDecoration { // 默认分隔条Drawable资源的ID,使用系统自带的 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) { // 使用TypedArray装载定义的ATTRS final TypedArray a = context.obtainStyledAttributes(ATTRS); // 获取系统提供的分隔条Drawable对象 mDivider = a.getDrawable(0); // 回收TypedArray所占用的空间 a.recycle(); setOrientation(orientation); } /** * 设置item的显示 水平 or 垂直 * * @param 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) { 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); 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); } } }
实现Adapter
package demo.turing.com.materialdesignwidget.recyclerView.adapter; import android.support.v7.widget.RecyclerView; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.TextView; import java.util.ArrayList; import java.util.Random; import demo.turing.com.materialdesignwidget.R; import demo.turing.com.materialdesignwidget.recyclerView.SimulatorData; import demo.turing.com.materialdesignwidget.recyclerView.model.SampleModel; /** * MyApp * * @author Mr.Yang on 2016-03-30 21:03. * @version 1.0 * @desc */ public class SampleRecyclerAdapter extends RecyclerView.Adapter<SampleRecyclerAdapter.ViewHolder> { // 模拟数据 private ArrayList<SampleModel> sampleData = SimulatorData.getSampleModelData(20); /** * 用于创建控件 * * @param parent * @param viewType * @return */ @Override public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) { // 获得列表项控件（LinearLayer对象） // list_basic_item.xml布局文件中只包含一个<LinearLayer>标签， // 在该标签中包含了一个<TextView>标签, item是LinearLayout对象 View item = LayoutInflater.from(parent.getContext()).inflate( R.layout.list_basic_item, parent, false); ViewHolder viewHolder = new ViewHolder(item); return viewHolder; } /** * 为控件设置数据 * * @param holder * @param position */ @Override public void onBindViewHolder(ViewHolder holder, int position) { // 获取当前item中显示的数据 final SampleModel rowData = sampleData.get(position); // 设置要显示的数据 holder.textViewSample.setText(rowData.getText()); // 设置tag holder.itemView.setTag(rowData); } @Override public int getItemCount() { return sampleData.size(); } /** * 删除指定的Item * * @param position */ public void removeData(int position) { sampleData.remove(position); // 通知RecyclerView控件某个Item已经被删除 notifyItemRemoved(position); } /** * 在指定位置添加一个新的Item * * @param positionToAdd */ public void addItem(int positionToAdd) { sampleData.add(positionToAdd, new SampleModel("新的列表项" + new Random().nextInt(10000))); // 通知RecyclerView控件插入了某个Item notifyItemInserted(positionToAdd); } /** * 对应Item中的控件 */ public static class ViewHolder extends RecyclerView.ViewHolder { private final TextView textViewSample; public ViewHolder(View itemView) { super(itemView); textViewSample = (TextView) itemView .findViewById(R.id.textViewSample); } } }
完成使用RecyclerView控件的最后工作
package demo.turing.com.materialdesignwidget.recyclerView; import android.os.Bundle; import android.support.v7.app.AppCompatActivity; import android.support.v7.widget.LinearLayoutManager; import android.support.v7.widget.RecyclerView; import demo.turing.com.materialdesignwidget.R; import demo.turing.com.materialdesignwidget.recyclerView.adapter.SampleRecyclerAdapter; public class RecyclerViewAct extends AppCompatActivity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_recycler_view); // 获取RecyclerView对象 RecyclerView recyclerView = (RecyclerView)findViewById(R.id.recycler_view); // 创建线性布局管理器（默认是垂直方向） LinearLayoutManager layoutManager = new LinearLayoutManager(this,LinearLayoutManager.VERTICAL,false); // 为RecyclerView指定布局管理对象 recyclerView.setLayoutManager(layoutManager); // 创建列表项分隔线对象 RecyclerView.ItemDecoration itemDecoration = new DividerItemDecoration(this,DividerItemDecoration.VERTICAL_LIST); // 为RecyclerView控件指定分隔线对象 recyclerView.addItemDecoration(itemDecoration); SampleRecyclerAdapter sampleRecyclerAdapter = new SampleRecyclerAdapter(); recyclerView.setAdapter(sampleRecyclerAdapter); } }
效果图
定制个性化分隔条
drawable\divider_custom.xml
<?xml version="1.0" encoding="utf-8"?> <shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="rectangle"> <size android:height="4dp"></size> <!--渐变色--> <gradient android:centerColor="#ff0000ff" android:endColor="#ffff0000" android:startColor="#ffff0000" android:type="linear"></gradient> </shape>
主题中设置
<item name="android:listDivider">@drawable/divider_custom</item>
瀑布流
StaggeredGridLayuoutAct.java
package demo.turing.com.materialdesignwidget.recyclerView; import android.os.Bundle; import android.support.v7.app.AppCompatActivity; import android.support.v7.widget.RecyclerView; import android.support.v7.widget.StaggeredGridLayoutManager; import java.util.List; import demo.turing.com.materialdesignwidget.R; import demo.turing.com.materialdesignwidget.recyclerView.adapter.StaggeredGridLayoutAdapter; import demo.turing.com.materialdesignwidget.recyclerView.model.SampleModel; /** * 不采用分隔线， 在Item的布局中 采用layout_margin的方式 * * 主要是动态设置View的高度 adapter类中的 onBindViewHolder */ public class StaggeredGridLayuoutAct extends AppCompatActivity { private RecyclerView recyclerView ; // 模拟数据 private List<SampleModel> sampleData = SimulatorData.getSampleModelData(20); @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_staggered_grid_layuout); // 查找组件 recyclerView = (RecyclerView) findViewById(R.id.id_rv_staggered); // 创建布局管理器 -3列，垂直 StaggeredGridLayoutManager manager = new StaggeredGridLayoutManager(3,StaggeredGridLayoutManager.VERTICAL); // 设置布局 recyclerView.setLayoutManager(manager); // Adapter StaggeredGridLayoutAdapter adapter = new StaggeredGridLayoutAdapter(this,sampleData); recyclerView.setAdapter(adapter); } }
activity_staggered_grid_layuout.xml
<?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:paddingBottom="@dimen/activity_vertical_margin" android:paddingLeft="@dimen/activity_horizontal_margin" android:paddingRight="@dimen/activity_horizontal_margin" android:paddingTop="@dimen/activity_vertical_margin" tools:context="demo.turing.com.materialdesignwidget.recyclerView.StaggeredGridLayuoutAct"> <android.support.v7.widget.RecyclerView android:id="@+id/id_rv_staggered" android:layout_width="match_parent" android:layout_height="match_parent"></android.support.v7.widget.RecyclerView> </RelativeLayout>
StaggeredGridLayoutAdapter.java
package demo.turing.com.materialdesignwidget.recyclerView.adapter; import android.content.Context; import android.support.v7.widget.RecyclerView; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.TextView; import java.util.ArrayList; import java.util.List; import demo.turing.com.materialdesignwidget.R; import demo.turing.com.materialdesignwidget.recyclerView.model.SampleModel; /** * MyApp * * @author Mr.Yang on 2016-03-31 20:19. * @version 1.0 * @desc */ public class StaggeredGridLayoutAdapter extends RecyclerView.Adapter<StaggeredGridLayoutAdapter.ViewHolder> { private Context context; private List<SampleModel> datas; private LayoutInflater inflater; // 随机高度的结合 private List<Integer> mHeights; /** * 构造函数 * * @param context * @param datas */ public StaggeredGridLayoutAdapter(Context context, List<SampleModel> datas) { this.context = context; this.datas = datas; this.inflater = LayoutInflater.from(context); // 初始化随机高度的集合 mHeights = new ArrayList<>(); for (int i = 0; i < datas.size(); i++) { mHeights.add((int)(100 + Math.random() * 300)); } } @Override public StaggeredGridLayoutAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) { // 动态加载Item的布局文件 View view = inflater.inflate(R.layout.list_basic_item, parent, false); // 实例化ViewHolder ViewHolder viewHolder = new ViewHolder(view); return viewHolder; } @Override public void onBindViewHolder(StaggeredGridLayoutAdapter.ViewHolder holder, int position) { // 获取当前Item中的显示的数据 SampleModel sampleModel = datas.get(position); //设置控件的随机高度 ViewGroup.LayoutParams lp = holder.itemView.getLayoutParams(); lp.height = mHeights.get(position); holder.itemView.setLayoutParams(lp); // 设置组件的值 holder.textView.setText(sampleModel.getText()); // 设置tag holder.itemView.setTag(sampleModel); } @Override public int getItemCount() { return datas.size(); } /** * ViewHoder */ class ViewHolder extends RecyclerView.ViewHolder { TextView textView; public ViewHolder(View itemView) { super(itemView); textView = (TextView) itemView .findViewById(R.id.textViewSample); } } }
list_basic_item.xml
<?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:layout_margin="3dp" android:background="#6495ED" android:gravity="center" android:orientation="horizontal"> <TextView android:id="@+id/textViewSample" android:layout_width="wrap_content" android:layout_height="wrap_content" android:textSize="20sp" android:text="演示"/> </RelativeLayout>
效果图
动画效果
// 默认动画效果 recyclerView.setItemAnimator(new DefaultItemAnimator());
notifyItemRemoved(position)
/** * 删除指定的Item * * @param position */ public void removeData(int position) { sampleData.remove(position); // 通知RecyclerView控件某个Item已经被删除 notifyItemRemoved(position); }
notifyItemInserted(positionToAdd)
/** * 在指定位置添加一个新的Item * * @param positionToAdd */ public void addItem(int positionToAdd) { sampleData.add(positionToAdd, new SampleModel("新的列表项" + new Random().nextInt(10000))); // 通知RecyclerView控件插入了某个Item notifyItemInserted(positionToAdd); }
为RecyclerView添加item的点击事件
方法一：利用回调的方式实现(不太完善，仍可实现)
实现步骤如下：
在adapter类中，定义接口，接口中定义两个方法分别对应click和longClick，定义完接口，添加接口和设置Adapter接口的方法：
/** * 接口 ，提供两个方法 */ public interface OnRecyclerViewItemClickListener{ // 单击事件 void onItemClick(View view ,int position); // 长按触发的事件 void onItemLongClick(View view ,int position); } // 定义OnRecyclerViewItemClickListener对象 public OnRecyclerViewItemClickListener mOnRecyclerViewItemClickListener ; // 暴漏给外部的set方法，持有OnRecyclerViewItemClickListener对象 public void setOnRecyclerViewItemClickListener(OnRecyclerViewItemClickListener listener){ this.mOnRecyclerViewItemClickListener = listener ; }
在onBindViewHolder方法中
// 点击事件 if(mOnRecyclerViewItemClickListener != null){ // click holder.itemView.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { mOnRecyclerViewItemClickListener.onItemClick(holder.itemView,position); } }); // longClick holder.itemView.setOnLongClickListener(new View.OnLongClickListener() { @Override public boolean onLongClick(View v) { mOnRecyclerViewItemClickListener.onItemLongClick(holder.itemView,position); return false; } }); }
做完这些事情，我们就可以在Activity或其他地方为RecyclerView添加项目点击事件了，
// 设置监事件 sampleRecyclerAdapter.setOnRecyclerViewItemClickListener(new SampleRecyclerAdapter.OnRecyclerViewItemClickListener() { @Override public void onItemClick(View view, int position) { Toast.makeText(RecyclerViewAct.this,"Click" + position ,Toast.LENGTH_SHORT).show(); } @Override public void onItemLongClick(View view, int position) { Toast.makeText(RecyclerViewAct.this,"LongClick" + position ,Toast.LENGTH_SHORT).show(); } });
完整代码如下：
RecyclerViewAct
package demo.turing.com.materialdesignwidget.recyclerView; import android.os.Bundle; import android.support.v7.app.AppCompatActivity; import android.support.v7.widget.DefaultItemAnimator; import android.support.v7.widget.LinearLayoutManager; import android.support.v7.widget.RecyclerView; import android.view.View; import android.widget.Toast; import demo.turing.com.materialdesignwidget.R; import demo.turing.com.materialdesignwidget.recyclerView.adapter.SampleRecyclerAdapter; public class RecyclerViewAct extends AppCompatActivity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_recycler_view); // 获取RecyclerView对象 RecyclerView recyclerView = (RecyclerView)findViewById(R.id.recycler_view); // 创建线性布局管理器（默认是垂直方向） LinearLayoutManager layoutManager = new LinearLayoutManager(this,LinearLayoutManager.VERTICAL,false); // 为RecyclerView指定布局管理对象 recyclerView.setLayoutManager(layoutManager); // 创建列表项分隔线对象 RecyclerView.ItemDecoration itemDecoration = new DividerItemDecoration(this,DividerItemDecoration.VERTICAL_LIST); // 为RecyclerView控件指定分隔线对象 recyclerView.addItemDecoration(itemDecoration); // 默认动画效果 recyclerView.setItemAnimator(new DefaultItemAnimator()); SampleRecyclerAdapter sampleRecyclerAdapter = new SampleRecyclerAdapter(); recyclerView.setAdapter(sampleRecyclerAdapter); // 设置监事件 sampleRecyclerAdapter.setOnRecyclerViewItemClickListener(new SampleRecyclerAdapter.OnRecyclerViewItemClickListener() { @Override public void onItemClick(View view, int position) { Toast.makeText(RecyclerViewAct.this,"Click" + position ,Toast.LENGTH_SHORT).show(); } @Override public void onItemLongClick(View view, int position) { Toast.makeText(RecyclerViewAct.this,"LongClick" + position ,Toast.LENGTH_SHORT).show(); } }); } }
SampleRecyclerAdapter
package demo.turing.com.materialdesignwidget.recyclerView.adapter; import android.support.v7.widget.RecyclerView; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.TextView; import java.util.ArrayList; import java.util.Random; import demo.turing.com.materialdesignwidget.R; import demo.turing.com.materialdesignwidget.recyclerView.SimulatorData; import demo.turing.com.materialdesignwidget.recyclerView.model.SampleModel; /** * MyApp * * @author Mr.Yang on 2016-03-30 21:03. * @version 1.0 * @desc * * * RecyclerView 点击事件 请看http://jcodecraeer.com/a/anzhuokaifa/androidkaifa/2014/1118/2004.html */ public class SampleRecyclerAdapter extends RecyclerView.Adapter<SampleRecyclerAdapter.ViewHolder> { // 模拟数据 private ArrayList<SampleModel> sampleData = SimulatorData.getSampleModelData(20); /** * 接口 ，提供两个方法 */ public interface OnRecyclerViewItemClickListener{ // 单击事件 void onItemClick(View view ,int position); // 长按触发的事件 void onItemLongClick(View view ,int position); } // 定义OnRecyclerViewItemClickListener对象 public OnRecyclerViewItemClickListener mOnRecyclerViewItemClickListener ; // 暴漏给外部的set方法，持有OnRecyclerViewItemClickListener对象 public void setOnRecyclerViewItemClickListener(OnRecyclerViewItemClickListener listener){ this.mOnRecyclerViewItemClickListener = listener ; } /** * 用于创建控件 * * @param parent * @param viewType * @return */ @Override public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) { // 获得列表项控件（LinearLayer对象） // list_basic_item.xml布局文件中只包含一个<LinearLayer>标签， // 在该标签中包含了一个<TextView>标签, item是LinearLayout对象 View item = LayoutInflater.from(parent.getContext()).inflate( R.layout.list_basic_item, parent, false); ViewHolder viewHolder = new ViewHolder(item); return viewHolder; } /** * 为控件设置数据 * * @param holder * @param position */ @Override public void onBindViewHolder(final ViewHolder holder, final int position) { // 获取当前item中显示的数据 final SampleModel rowData = sampleData.get(position); // 设置要显示的数据 holder.textViewSample.setText(rowData.getText()); // 设置tag holder.itemView.setTag(rowData); // 点击事件 if(mOnRecyclerViewItemClickListener != null){ // click holder.itemView.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { // 通过getLayoutPosition，防止position错位 int layoutPosition = holder.getLayoutPosition(); mOnRecyclerViewItemClickListener.onItemClick(holder.itemView,layoutPosition); } }); // longClick holder.itemView.setOnLongClickListener(new View.OnLongClickListener() { @Override public boolean onLongClick(View v) { int layoutPosition = holder.getLayoutPosition(); mOnRecyclerViewItemClickListener.onItemLongClick(holder.itemView,layoutPosition); return false; } }); } } @Override public int getItemCount() { return sampleData.size(); } /** * 删除指定的Item * * @param position */ public void removeData(int position) { sampleData.remove(position); // 通知RecyclerView控件某个Item已经被删除 notifyItemRemoved(position); } /** * 在指定位置添加一个新的Item * * @param positionToAdd */ public void addItem(int positionToAdd) { sampleData.add(positionToAdd, new SampleModel("新的列表项" + new Random().nextInt(10000))); // 通知RecyclerView控件插入了某个Item notifyItemInserted(positionToAdd); } /** * 对应Item中的控件 */ public static class ViewHolder extends RecyclerView.ViewHolder { private final TextView textViewSample; public ViewHolder(View itemView) { super(itemView); textViewSample = (TextView) itemView .findViewById(R.id.textViewSample); } } }
方法二：使用观察者模式实现
原理：
为RecyclerView的每个子item设置setOnClickListener，然后在onClick中再调用一次对外封装的接口，将这个事件传递给外面的调用者。而“为RecyclerView的每个子item设置setOnClickListener”在Adapter中设置。其实直接在onClick中也能完全处理item的点击事件，但是这样会破坏代码的逻辑。
步骤
在自定义的adapter（记得implements View.OnClickListener，下面有个onClick方法）中定义如下接口,模拟ListView的OnItemClickListener：
//define interface public static interface OnRecyclerViewItemClickListener { void onItemClick(View view , String data); }
声明一个这个接口的变量：
private OnRecyclerViewItemClickListener mOnItemClickListener = null;
在onCreateViewHolder()中为每个item添加点击事件：
@Override public ViewHolder onCreateViewHolder(ViewGroup viewGroup, int viewType) { View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.item, viewGroup, false); ViewHolder vh = new ViewHolder(view); //将创建的View注册点击事件 view.setOnClickListener(this); return vh; }
将点击事件转移给外面的调用者：
@Override public void onClick(View v) { if (mOnItemClickListener != null) { //注意这里使用getTag方法获取数据 mOnItemClickListener.onItemClick(v,(String)v.getTag()); } }
意上面调用接口的onItemClick()中的v.getTag()方法，这需要在onBindViewHolder()方法中设置和item相关的数据
@Override public void onBindViewHolder(ViewHolder viewHolder, int position) { viewHolder.mTextView.setText(datas[position]); //将数据保存在itemView的Tag中，以便点击时进行获取 viewHolder.itemView.setTag(datas[position]); }
最后暴露给外面的调用者，定义一个设置Listener的方法（）：
public void setOnItemClickListener(OnRecyclerViewItemClickListener listener) { this.mOnItemClickListener = listener; }
以上所有步骤都发生在自定义的adapter中，典型的观察者模式，有点绕的地方在于，这里涉及到两个观察者模式的使用，view的setOnClickListener本来就是观察者模式，我们将这个观察者模式的事件监听传递给了我们自己的观察者模式。
在Activity中使用
mRecyclerView = (RecyclerView)findViewById(R.id.my_recycler_view); //创建默认的线性LayoutManager mLayoutManager = new LinearLayoutManager(this); mRecyclerView.setLayoutManager(mLayoutManager); //如果可以确定每个item的高度是固定的，设置这个选项可以提高性能 mRecyclerView.setHasFixedSize(true); //创建并设置Adapter mAdapter = new MyAdapter(data); mRecyclerView.setAdapter(mAdapter); mAdapter.setOnItemClickListener(new OnRecyclerViewItemClickListener(){ @Override public void onItemClick(View view , String data){ Toast.makeText(MainActivity.this, data, 600).show(); } });
