RecyclerView 制作瀑布流图片

这是瀑布流的效果图

RecyclerView（ListView的升级版）

加载图片用的是第三方图片加载框架

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在Xml中

 <?xml version="1.0" encoding="utf-8"?>
 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
     android:id="@+id/activity_main"
     android:layout_width="match_parent" android:layout_height="match_parent">
 
     <android.support.v7.widget.RecyclerView android:id="@+id/gr_id"
         android:layout_width="match_parent" android:layout_height="match_parent"/>
 </RelativeLayout>

这是Activity 初始化组件

 public class MainActivity extends AppCompatActivity {
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);
 
         RecyclerView recyclerView = (RecyclerView) findViewById(R.id.gr_id);
         //设置布局管理器
         recyclerView.setLayoutManager(new StaggeredGridLayoutManager(3,StaggeredGridLayoutManager.VERTICAL));
         //添加分隔符
         recyclerView.addItemDecoration(new DividerGridItemDecoration(this));
 
         MyAdapter adapter = new MyAdapter(this, Arrays.asList(ImageUrlArrays.IMAGE_URL_ARRAYS));
         //设置Adapter
         recyclerView.setAdapter(adapter);
 
         //为子条目设置点击事件
         adapter.setOnRecyclerViewItemViewListener(new RecyclerViewItemViewListener() {
             @Override
             public void onClickListener(RecyclerView.ViewHolder viewHolder, int position) {
                 Toast.makeText(MainActivity.this, "点击事件："+position, Toast.LENGTH_SHORT).show();
             }
 
             @Override
             public void onLongClickListener(RecyclerView.ViewHolder viewHolder, int position) {
                 Toast.makeText(MainActivity.this, "长按事件："+position, Toast.LENGTH_SHORT).show();
             }
         });
     }
 
     @Override
     public boolean onCreateOptionsMenu(Menu menu) {
         getMenuInflater().inflate(R.menu.main,menu);
         return super.onCreateOptionsMenu(menu);
     }
 
     @Override
     public boolean onOptionsItemSelected(MenuItem item) {
         switch (item.getItemId()){
             case R.id.clear_disk://清除硬盘缓存
                 Toast.makeText(this, "清除硬盘缓存!", Toast.LENGTH_SHORT).show();
                 WXHLImageLoader.getInstance().clearDiskCache();
                 break;
             case R.id.clear_id://清除内存缓存
                 Toast.makeText(this, "清除内存缓存!", Toast.LENGTH_SHORT).show();
                 WXHLImageLoader.getInstance().clearMemoryCache();
                 break;
         }
         return super.onOptionsItemSelected(item);
     }
 }

需要设置数据就要newAdapter 这个Adapter是必须继承RecyclerView的Adapter 其中还要传入ViewHolder

这个ViewHolder也是要继承RecyclerView的ViewHolder

 class MyAdapter extends RecyclerView.Adapter<MyAdapter.ViewHolder>{
 
     private Context context;
     private List<String> list;
     private List<Integer> heightList;
     private RecyclerViewItemViewListener listener ;
 
     public MyAdapter(Context context, List<String> list) {
         this.context = context;
         this.list = list;
 
         heightList = new ArrayList<>();
         for (int i = 0; i < list.size() ; i++) {
             int height = (int) (Math.random()*400 + 400);
             heightList.add(height);
         }
 
     }
 
     /**
      * 给itemView监听器赋值
      * @param listener
      */
     public void setOnRecyclerViewItemViewListener(RecyclerViewItemViewListener listener){
         this.listener = listener;
     }
 
     int i = 0;
     /**
      * 创建ViewHolder对contentView进行复用
      * @param parent
      * @param viewType
      * @return
      */
     @Override
     public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
         i++;
         L.e("----------------onCreateViewHolder-----------i:"+i);
         View contentView = LayoutInflater.from(context).inflate(R.layout.activity_main_item,parent,false);
         return new ViewHolder(contentView);
     }
 
     /**
      * 进行数据绑定，itemView设置数据
      * @param holder
      * @param position
      */
     @Override
     public void onBindViewHolder(ViewHolder holder, int position) {
 
         //改变holder.button的高度
         int height = heightList.get(position);
         ViewGroup.LayoutParams lp = holder.imageView.getLayoutParams();
         lp.height = height;
         holder.imageView.setLayoutParams(lp);
 
         L.e("----------------onBindViewHolder-----------position："+position);
         WXHLImageLoader.getInstance().displayImage(list.get(position),holder.imageView);
         holder.setPosition(position);
     }
 
     @Override
     public int getItemCount() {
         return list.size();
     }
 
     class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener,View.OnLongClickListener{
         ImageView imageView;
         private int position;
 
         public ViewHolder(View itemView) {
             super(itemView);
             //为ViewHolder中的组件进行赋值
             imageView = (ImageView) itemView.findViewById(R.id.id_but);
 
             if(listener != null){//判断RecyclerViewItemViewListener是否为空，
                                 // 若为空，不能给子条目设置点击事件，否则会出现空指针
                 itemView.setOnClickListener(this);
                 itemView.setOnLongClickListener(this);
             }
         }
 
         public void setPosition(int position) {
             this.position = position;
         }
 
         @Override
         public void onClick(View v) {
             switch (v.getId()){
                 case R.id.item_id://itemView的点击事件
                     listener.onClickListener(this,position);
                     break;
             }
         }
 
         @Override
         public boolean onLongClick(View v) {//itemView的长按事件
             listener.onLongClickListener(this,position);
             return true;
         }
     }
 }

在用RecyclerView时  是没有监听事件的  这个事件需要我们自己去写

新建一个接口

 public interface RecyclerViewItemViewListener {
 
     /**
      * itemView的点击事件
      * @param viewHolder
      * @param position
      */
     void onClickListener(RecyclerView.ViewHolder viewHolder, int position);
 
     /**
      * 是itemView的长按事件
      * @param viewHolder
      * @param position
      */
     void onLongClickListener(RecyclerView.ViewHolder viewHolder, int position);
 
 }