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

-------------------------------------

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);

}