RecyclerView 的实现

先说使用RecyclerView要实现的必要步骤：

1.用LayoutManager管理它的布局：横向或竖向，不同的布局风格；
2.实现Adapter类继承RecyclerView.Adapter类；
3.RecyclerView.addItemDecoration(newDividerItemDecoration()):
制作item之间的分割线；
4.RecyclerView.setItemAnimator（new MyItemAnimator()）:制作删除添加item等操作的动画效果；
5.实现RecyclerView的事件监听器：点击，长按等

 mRecyclerView = findView(R.id.id_recyclerview);
//设置布局管理器
mRecyclerView.setLayoutManager(layout);
//设置adapter
mRecyclerView.setAdapter(adapter)
//设置Item增加、移除动画
mRecyclerView.setItemAnimator(new DefaultItemAnimator());
//添加分割线
mRecyclerView.addItemDecoration(new DividerItemDecoration(
            getActivity(), DividerItemDecoration.HORIZONTAL_LIST));

实现步骤

使用RecyclerView之前我们要导入相对应的包：

compile 'com.android.support:recyclerview-v7:+'

布局文件：主布局

 <android.support.v7.widget.RecyclerView
    android:id="@+id/recyclerview"
    android:layout_width="match_parent"
    android:layout_height="match_parent"/>  

item子布局：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:background="@drawable/item_bg"
android:layout_margin="3dp"
android:layout_height="72dp">    
<TextView
    android:layout_width="72dp"
    android:layout_height="match_parent"
    android:id="@+id/Item_text"
    android:gravity="center" />

</LinearLayout>

一.设置它的布局管理：

LinearLayoutManager linearLayoutManager  = new LinearLayoutManager(this,LinearLayoutManager.VERTICAL,false);        
recyclerView.setLayoutManager(linearLayoutManager);

三个布局：直接上源代码

1 .线性布局：

  /**  * @param context       Current context, will be used to access resources.
 * @param orientation   Layout orientation. Should be {@link #HORIZONTAL} or{@link#VERTICAL}.
 * @param reverseLayout When set to true, layouts from end to start.
 */
public LinearLayoutManager(Context context, int orientation, boolean reverseLayout) {
    mAnchorInfo = new AnchorInfo();
    setOrientation(orientation);
    setReverseLayout(reverseLayout);
}

2.格子布局：

  /** * @param context Current context, will be used to access resources.
 * @param spanCount The number of columns or rows in the grid
 * @param orientation Layout orientation. Should be {@link #HORIZONTAL} or {@link
 *                      #VERTICAL}.
 * @param reverseLayout When set to true, layouts from end to start.
 */
public GridLayoutManager(Context context, int spanCount, int orientation,
        boolean reverseLayout) {
    super(context, orientation, reverseLayout);
    setSpanCount(spanCount);
}

3.瀑布流布局：

 /**  * Creates a StaggeredGridLayoutManager with given parameters.
 *
 * @param spanCount   If orientation is vertical, spanCount is number of columns. If
 *                    orientation is horizontal, spanCount is number of rows.
 * @param orientation {@link #VERTICAL} or {@link #HORIZONTAL}
 */
public StaggeredGridLayoutManager(int spanCount, int orientation) {
    mOrientation = orientation;
    setSpanCount(spanCount);
}

二.创建适配器

public class MyRecyclerViewAdatper extends RecyclerView.Adapter<RecyclerView.ViewHolder>  {
  private LayoutInflater inflater;
  private Context context;
  private List<String> datas;
private OnitemClickListener onitemClickListener;

public  interface  OnitemClickListener{
    void onItemClick(View view,int positon);
    void onItemLongClick(View view,int position);
}

public void setOntermClickListener(OnitemClickListener ontermClickListener){
    this.onitemClickListener = ontermClickListener;
}
   public MyAdapter(Context context,List<String> datas){
    this.context = context;
    this.datas = datas;
    inflater = LayoutInflater.from(context);

}
@Override
public long getItemId(int position) {//返回数据的id
    return super.getItemId(position);
}

@Override
public int getItemCount() { //返回数据的数量
    return datas.size();
}

@Override
public int getItemViewType(int position) { //放回item的类型（制定不同风格的item要用到）
    return position;
}

@Override
public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
 //这个函数是初始化视图，返回一个ViewHolder，方法是把View直接封装在ViewHolder中，然后我们面向的是ViewHolder这个实例
    View view  = inflater.inflate(R.layout.item,parent,false);
    MyViewHolder myViewHolder = new MyViewHolder(view);
    return myViewHolder;
}

@Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
      //对视图的操作主要放在这里
      holder.textView.setText(datas.get(position));
   if(onitemClickListener!=null){
        holder.itemView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                onitemClickListener.onItemClick(holder.itemView, position);
            }
        });
        holder.itemView.setOnLongClickListener(new View.OnLongClickListener() {
            @Override
            public boolean onLongClick(View v) {
                onitemClickListener.onItemLongClick(holder.itemView, position);
                return false;
            }
        });
    }
}
 public void addData(int pos){
    datas.add(pos,"Insert one");
    notifyItemInserted(pos);
}

public void deletData(int pos){
    datas.remove(pos);
    notifyItemRemoved(pos);
}
  //就是一个持有者的类，他里面一般没有方法，只有属性，作用就是一个临时的储存器，
  //把你getView方法中每次返回的View存起来，可以下次再用。这样做的好处就是不必每次都到布局文件中去拿到你的View，提高了效率。
class MyViewHolder extends RecyclerView.ViewHolder{
TextView textView;
public MyViewHolder(View itemView) {
    super(itemView);
    textView = (TextView)itemView.findViewById(R.id.Item_text);
}
}

说明：

notifyItemInserted(pos);//增加item  
notifyItemRemoved(pos);//删除item