recycleview 的 ItemView常用验证

引用：

dependencies {...    compile 'com.android.support:recyclerview-v7:25.3.1'}

代码：
1、item布局

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="match_parent"    android:layout_height="wrap_content"    android:orientation="vertical">    <TextView        android:id="@+id/id_num"        android:layout_width="match_parent"        android:layout_height="100dp"        android:background="#ff5500"        android:gravity="center"        android:text="hello" />    <TextView        android:layout_width="match_parent"        android:layout_height="match_parent"        android:background="@color/colorPrimary" /></LinearLayout>

2、适配器代码

package com.example.lihui.testrecycleview;import android.content.Context;import android.support.v7.widget.RecyclerView;import android.util.Log;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;import android.widget.TextView;import java.util.List;/** * Created by lihui on 2017/8/22. */public class MyRecyclerAdapter extends RecyclerView.Adapter<MyRecyclerAdapter.MyViewHolder> {    private static final String TAG = "MyRecyclerAdapter";    private List<String> mData;    private Context mContext;    private LayoutInflater inflater;    public MyRecyclerAdapter(Context context, List<String> data) {        this.mContext = context;        this.mData = data;        inflater = LayoutInflater.from(mContext);    }    @Override    public int getItemCount() {        return mData.size();    }    @Override    public void onViewRecycled(MyViewHolder holder) {        super.onViewRecycled(holder);        Log.d(TAG, "onViewRecycled: " + holder.tv.getText().toString() + ", position: " + holder.getAdapterPosition());    }    //填充onCreateViewHolder方法返回的holder中的控件    @Override    public void onBindViewHolder(final MyViewHolder holder, final int position) {        Log.d(TAG, "onBindViewHolder: 验证是否重用了");        Log.d(TAG, "onBindViewHolder: 重用了" + holder.tv.getTag());        Log.d(TAG, "onBindViewHolder: 放到了" + mData.get(position));        holder.tv.setText(mData.get(position));        holder.tv.setTag(mData.get(position));    }    //重写onCreateViewHolder方法，返回一个自定义的ViewHolder    @Override    public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {        Log.d(TAG, "onCreateViewHolder");        View view = inflater.inflate(R.layout.item_layout, parent, false);        return new MyViewHolder(view);    }    static class MyViewHolder extends RecyclerView.ViewHolder {        TextView tv;        public MyViewHolder(View view) {            super(view);            tv = (TextView) view.findViewById(R.id.id_num);        }    }}

3、activity代码

package com.example.lihui.testrecycleview;import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.support.v7.widget.LinearLayoutManager;import android.support.v7.widget.RecyclerView;import java.util.ArrayList;import java.util.List;public class MainActivity extends AppCompatActivity {    private RecyclerView recyclerView;    private List<String> mData;    private MyRecyclerAdapter recycleAdapter;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        recyclerView = (RecyclerView) findViewById(R.id.id_recyclerView);        initData();        recycleAdapter = new MyRecyclerAdapter(MainActivity.this, mData);        //设置布局管理器 , 将布局设置成纵向        LinearLayoutManager linerLayoutManager = new LinearLayoutManager(this, LinearLayoutManager.VERTICAL, false);        recyclerView.setLayoutManager(linerLayoutManager);        // ...        recyclerView.setAdapter(recycleAdapter);        // ...    }    private void initData() {        mData = new ArrayList<>();        mData.add("test1"); //0        mData.add("test2"); //0        mData.add("test3"); //0        mData.add("test4"); //0        mData.add("test5"); //0        mData.add("test6"); //0        mData.add("test7"); //0        mData.add("test8"); //0        mData.add("test9"); //0        mData.add("test10"); //0        mData.add("test11"); //0        mData.add("test12"); //0        mData.add("test13"); //0        mData.add("test14"); //0    }}

4、recycleview 布局

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:app="http://schemas.android.com/apk/res-auto"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"    tools:context="com.example.lihui.testrecycleview.MainActivity">    <android.support.v7.widget.RecyclerView        android:id="@+id/id_recyclerView"        android:layout_width="match_parent"        android:layout_height="match_parent" /></LinearLayout>

log打印：

08-22 23:08:25.601 10929-10929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onCreateViewHolder08-22 23:08:25.604 10929-10929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 验证是否重用了08-22 23:08:25.604 10929-10929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 重用了null08-22 23:08:25.604 10929-10929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 放到了test108-22 23:08:25.605 10929-10929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onCreateViewHolder08-22 23:08:25.608 10929-10929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 验证是否重用了08-22 23:08:25.608 10929-10929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 重用了null08-22 23:08:25.608 10929-10929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 放到了test208-22 23:08:25.608 10929-10929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onCreateViewHolder08-22 23:08:25.609 10929-10929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 验证是否重用了08-22 23:08:25.609 10929-10929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 重用了null08-22 23:08:25.609 10929-10929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 放到了test308-22 23:08:25.610 10929-10929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onCreateViewHolder08-22 23:08:25.611 10929-10929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 验证是否重用了08-22 23:08:25.611 10929-10929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 重用了null08-22 23:08:25.611 10929-10929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 放到了test408-22 23:08:25.611 10929-10929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onCreateViewHolder08-22 23:08:25.614 10929-10929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 验证是否重用了08-22 23:08:25.614 10929-10929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 重用了null08-22 23:08:25.614 10929-10929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 放到了test51、手机一屏显示5条往上滑动：08-22 23:18:19.953 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onCreateViewHolder08-22 23:18:19.956 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 验证是否重用了08-22 23:18:19.956 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 重用了null08-22 23:18:19.956 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 放到了test108-22 23:18:19.956 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onCreateViewHolder08-22 23:18:19.965 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 验证是否重用了08-22 23:18:19.965 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 重用了null08-22 23:18:19.965 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 放到了test208-22 23:18:19.972 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onCreateViewHolder08-22 23:18:19.973 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 验证是否重用了08-22 23:18:19.973 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 重用了null08-22 23:18:19.973 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 放到了test308-22 23:18:19.973 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onCreateViewHolder08-22 23:18:19.974 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 验证是否重用了08-22 23:18:19.974 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 重用了null08-22 23:18:19.974 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 放到了test408-22 23:18:19.975 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onCreateViewHolder08-22 23:18:19.976 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 验证是否重用了08-22 23:18:19.976 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 重用了null08-22 23:18:19.976 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 放到了test508-22 23:18:28.460 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onCreateViewHolder08-22 23:18:28.467 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 验证是否重用了08-22 23:18:28.467 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 重用了null08-22 23:18:28.467 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 放到了test608-22 23:18:40.344 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onCreateViewHolder08-22 23:18:40.352 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 验证是否重用了08-22 23:18:40.352 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 重用了null08-22 23:18:40.352 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 放到了test708-22 23:18:45.058 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onCreateViewHolder08-22 23:18:45.065 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 验证是否重用了08-22 23:18:45.065 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 重用了null08-22 23:18:45.065 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 放到了test808-22 23:18:47.950 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onCreateViewHolder08-22 23:18:47.955 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 验证是否重用了08-22 23:18:47.955 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 重用了null08-22 23:18:47.955 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 放到了test908-22 23:18:48.658 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onViewRecycled: test1, position: 008-22 23:18:51.126 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 验证是否重用了***********************************************************08-22 23:18:51.127 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 重用了test1***********************************************************08-22 23:18:51.127 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 放到了test10从第10个开始重用（第一个）08-22 23:18:48.658 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onViewRecycled: test1, position: 008-22 23:18:51.126 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 验证是否重用了08-22 23:18:51.127 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 重用了test108-22 23:18:51.127 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 放到了test1008-22 23:20:53.751 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onViewRecycled: test2, position: 1                                                                                      [ 08-22 23:20:53.782 27800:27800 I/         ]                                                                                      power log dlsym ok08-22 23:20:53.838 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 验证是否重用了08-22 23:20:53.838 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 重用了test208-22 23:20:53.838 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 放到了test1108-22 23:20:54.528 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onViewRecycled: test3, position: 208-22 23:20:55.127 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 验证是否重用了08-22 23:20:55.127 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 重用了test308-22 23:20:55.127 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 放到了test1208-22 23:20:55.140 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onViewRecycled: test4, position: 308-22 23:21:00.171 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 验证是否重用了08-22 23:21:00.171 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 重用了test408-22 23:21:00.171 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 放到了test1308-22 23:21:00.351 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onViewRecycled: test5, position: 408-22 23:21:00.667 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 验证是否重用了08-22 23:21:00.667 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 重用了test508-22 23:21:00.667 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onBindViewHolder: 放到了test1408-22 23:21:01.027 18929-18929/com.example.lihui.testrecycleview D/MyRecyclerAdapter: onViewRecycled: test6, position: 5研究发现，具体从哪一个开始重用不确定！！！！内部已经实现了，算法什么样子，我们不需要知道！！！