RecyclerView 使用步骤

一，引入RecyclerView包

1. AndroidStudio

确保 Android support 包更新到最新版本 
 
在model的build.gradle中添加依赖, 23表示当前使用的编译android版本 
 
然后sync procjet, 就可以在project视图下看到包已经导入 

二 使用RecyclerView先实现ListView效果

MainActivity.Java

public class MainActivity extends AppCompatActivity {    private static final String TAG = "MainActivity";    private RecyclerView mRecyclerView;    private MyAdapter mMyAdapter;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        mRecyclerView = (RecyclerView) findViewById(R.id.rv_main);        mRecyclerView.setLayoutManager(new LinearLayoutManager(this));        mMyAdapter = new MyAdapter(MainActivity.this, initData());        mRecyclerView.setAdapter(mMyAdapter);    }    private List<String> initData() {        List<String> datas = new ArrayList<String>();        for (int i = 0; i <= 100; i++) {            datas.add("item:" + i);        }        return datas;    }}
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MyAdapter.java

public class MyAdapter extends RecyclerView.Adapter<MyAdapter.MyViewHolder> {    private static final String TAG = "MyAdapter";    private List<String> datas;    private LayoutInflater inflater;    public MyAdapter(Context context, List<String> datas) {        this.datas = datas;        inflater = LayoutInflater.from(context);    }    public class MyViewHolder extends RecyclerView.ViewHolder {        private TextView title;        public MyViewHolder(View itemView) {            super(itemView);            title = (TextView) itemView.findViewById(R.id.rv_main_item_title);        }    }    @Override    public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {        Log.e(TAG, "create a new item");        MyViewHolder holder = new MyViewHolder(inflater.inflate(R.layout.rv_main_item, parent, false));        return holder;    }    @Override    public void onBindViewHolder(MyViewHolder holder, int position) {        Log.e(TAG, "set value to item:" + position);        holder.title.setText(datas.get(position));    }    @Override    public int getItemCount() {        return datas.size();    }}
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activity_main.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"    tools:context="org.xm.recyclerviewsimple.MainActivity">    <android.support.v7.widget.RecyclerView        android:id="@+id/rv_main"        android:layout_width="match_parent"        android:layout_height="match_parent">    </android.support.v7.widget.RecyclerView></RelativeLayout>
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rv_main_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="wrap_content"    android:orientation="vertical">    <TextView        android:id="@+id/rv_main_item_title"        android:layout_width="match_parent"        android:layout_height="50dp"        android:gravity="center"        android:text="T.T"        android:textSize="20sp" /></RelativeLayout>

这里图片就不上了

给每个item添加一条分解线:

1. 不需要添加分割线, 通过背景设置显示间隔

为每个item添加背景白色,并且设置间隔1dp 
rv_main_item.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="match_parent"    android:layout_height="wrap_content"    android:background="#ffffff"    android:layout_marginBottom="1dp"    android:orientation="vertical">    ...</RelativeLayout>
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再给RecyclerView添加黑色背景 
activity_main.xml

    <android.support.v7.widget.RecyclerView        android:id="@+id/rv_main"        android:background="#000000"        android:layout_width="match_parent"        android:layout_height="match_parent">    </android.support.v7.widget.RecyclerView>
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2. 自定义分割线

自定义drawable文件 
rm_main_item_divicer.xml

<?xml version="1.0" encoding="utf-8"?><shape xmlns:android="http://schemas.android.com/apk/res/android"    android:shape="rectangle">    <gradient        android:centerColor="#ff00ff00"        android:endColor="#ff0000ff"        android:startColor="#ffff0000"        android:type="linear" />    <size android:height="1dp"/></shape>
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自定义分割线

class MyItemDivider extends RecyclerView.ItemDecoration {    private Drawable mDrawable;    public MyItemDivider(Context context, int resId) {        mDrawable = context.getResources().getDrawable(resId);    }    @Override    public void onDrawOver(Canvas c, RecyclerView parent, RecyclerView.State state) {        int left = parent.getPaddingLeft();        int right = parent.getWidth() - parent.getPaddingRight();        int childCount = parent.getChildCount();        for (int i = 0; i < childCount; i++) {            View child = parent.getChildAt(i);            RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams();            int top = child.getBottom() + params.bottomMargin;            int bottom = top + mDrawable.getIntrinsicHeight();            mDrawable.setBounds(left, top, right, bottom);            mDrawable.draw(c);        }    }    @Override    public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {        outRect.set(0, 0, 0, mDrawable.getIntrinsicWidth());    }}
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然后添加到RecyclerView中: 
mRecyclerView.addItemDecoration(new MyItemDivider(this,R.drawable.rv_main_item_divider));

修改布局管理器

上面的代码布局管理器使用的是LinerlayoutManager, 如果这个时候我们将布局管理器修改为 GridLayoutManager 会是什么效果呢?

// mRecyclerView.setLayoutManager(new LinearLayoutManager(this));mRecyclerView.setLayoutManager(new GridLayoutManager(this,3));

确实很屌, 就一行代码,就改成了gridview. 注意刚刚写得分割线, 如果修改为 grideview之后是不能用的,所以这里我使用的是 利用背景添加分割线的方式, 很简单了, 只需要同时添加 margin_bottom 和 margin_right 以及修改背景颜色即可.

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="match_parent"    android:layout_height="wrap_content"    android:layout_marginRight="1px"    android:layout_marginTop="1px"    android:background="#ffffff"    android:orientation="vertical">    ...</RelativeLayout>
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如果使用 StaggeredGridLayoutManager, 可以很容易实现瀑布流布局

// mRecyclerView.setLayoutManager(new LinearLayoutManager(this));// mRecyclerView.setLayoutManager(new GridLayoutManager(this,3));mRecyclerView.setLayoutManager(new StaggeredGridLayoutManager(4, StaggeredGridLayoutManager.VERTICAL));

实现方法简单, 在onBindViewHolder中使用随机数来产生iteam的高度:

@Overridepublic void onBindViewHolder(MyViewHolder holder, int position) {    Log.e(TAG, "set value to item:" + position);    holder.title.setText(datas.get(position));    int height = Math.abs((new Random().nextInt()) % 300);    if (height < 200) {        height += 200;    }    holder.title.setHeight(height);}
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注意将原来的item配置layout文件修改一下宽高:

<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="wrap_content"    android:layout_height="wrap_content"    android:layout_marginRight="1px"    android:layout_marginTop="1px"    android:background="#ffffff"    android:orientation="vertical">    <TextView        android:id="@+id/rv_main_item_title"        android:layout_width="match_parent"        android:layout_height="match_parent"        android:gravity="center"        android:text="T.T"        android:textSize="20sp" /></RelativeLayout>
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添加点击事件和长按事件

首先在 MyAdapter中定义两个click事件接口, 以及setter:

public interface OnItemClickListener {    public void onClick(View parent, int position);}public interface OnItemLongClickListener {    public boolean onLongClick(View parent, int position);}public void setOnItemClickListener(OnItemClickListener l) {    this.mOnItemClickListener = l;}public void setOnItemLongClickListener(OnItemLongClickListener l) {    this.mOnItemLongClickListener = l;}
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在onBindViewHolder中设置事件响应:

@Overridepublic void onBindViewHolder(final MyViewHolder holder, final int position) {    //...    // 设置事件响应    if (mOnItemClickListener != null) {        holder.itemView.setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View view) {                int pos = holder.getLayoutPosition();                mOnItemClickListener.onClick(holder.itemView, pos);            }        });    }    if (mOnItemLongClickListener != null) {        holder.itemView.setOnLongClickListener(new View.OnLongClickListener() {            @Override            public boolean onLongClick(View view) {                int pos = holder.getLayoutPosition();                mOnItemLongClickListener.onLongClick(holder.itemView, pos);                return false;            }        });    }}
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在MainActivity中添加事件:

mMyAdapter.setOnItemClickListener(new MyAdapter.OnItemClickListener() {    @Override    public void onClick(View parent, int position) {        mMyAdapter.addData(position,"add item:"+position);        mMyAdapter.notifyItemInserted(position);    }});mMyAdapter.setOnItemLongClickListener(new MyAdapter.OnItemLongClickListener() {    @Override    public boolean onLongClick(View parent, int position) {        mMyAdapter.removeData(position);        mMyAdapter.notifyItemRemoved(position);        return false;    }});
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注意: 
这里点击事件的操作是再添加一个item, 长按事件是删除一个item. 我们还需要在MyAdapter中添加 addData(), 和removeData() 两个方法:

    public void addData(int position, String content){        datas.add(position,content);    }    public void removeData(int position){        datas.remove(position);    }
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然后配合自带的 notifyItemInserted(), 和notifyItemRemoved() 可以很轻松实现添加item和删除item炒作. 赶紧试试吧!

最后的最后, 再给每个item添加上press的selector, 增加用户体验: 
定义rv_main_item_selector.xml文件

<?xml version="1.0" encoding="utf-8"?><selector xmlns:android="http://schemas.android.com/apk/res/android">    <item android:state_pressed="true" android:drawable="@color/colorPrimary" />    <item android:drawable="@android:color/white" /></selector>
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将item的背景设置成selector: 
android:background="@drawable/rv_main_item_selector" 

以上都没有贴图 自己可以试下效果