为RecyclerView的Item设置点击事件

在之前的UIBestPractice中，我们使用了在创建View的时候添加点击事件，但是有的时候这样做并不方便，所以又从网上找到了另一种实现方式，当ItemView attach RecyclerView时实现,下文转载自：https://segmentfault.com/a/1190000014509249。

第一步：

在RecyclerView的Adapyer中定义单击事件的回调接口：

/**
 * 定义RecyclerView选项单击事件的回调接口
 */
public interface OnItemClickListener{
    //参数（父组件，当前单击的View,单击的View的位置，数据）
    void onItemClick(RecyclerView parent,View view, int position, String data);
}

第二步：

在RecyclerView的Adapyer中声明该接口，并提供setter方法：

private OnItemClickListener onItemClickListener;
public void setOnItemClickListener(OnItemClickListener onItemClickListener){
    this.onItemClickListener = onItemClickListener;
}

第三步：

在RecyclerView的Adapyer类实现View.OnClickListener接口，并重写onClick(View view)方法，然后设置给接口的事件监听：

public class RvAdapter1 extends RecyclerView.Adapter<RvAdapter1.DataViewHolder> implements View.OnClickListener{
    ...
    view.setOnClickListener(this);//设置监听器
    ...
    @Override
    public void onClick(View view) {
        //根据RecyclerView获得当前View的位置
        int position = recyclerView.getChildAdapterPosition(view);
        //程序执行到此，会去执行具体实现的onItemClick()方法
        if (onItemClickListener!=null){
            onItemClickListener.onItemClick(recyclerView,view,position,mList.get(position));
        }
    }
    ...
}

第四步：

在MainActivity中通过Adapter设置每个Item的单击事件：

adapter.setOnItemClickListener(new RvAdapter1.OnItemClickListener() {
    @Override
    public void onItemClick(RecyclerView parent, View view, int position, String data) {
        Toast.makeText(MainActivity.this, data, Toast.LENGTH_SHORT).show();
    }
});

参考代码

Adapter

/**
 * Created by jzman on 2017/5/13 0013.
 * RecycleView的Adapter
 */
public class RvAdapter1 extends RecyclerView.Adapter<RvAdapter1.DataViewHolder> implements View.OnClickListener{
    private Context mContext;
    private RecyclerView recyclerView;
    private ArrayList<String> mList;

    public RvAdapter1() {}

    public RvAdapter1(Context mContext, ArrayList<String> mList) {
        this.mContext = mContext;
        this.mList = mList;
    }

    /**
     * 用于创建ViewHolder
     * @param parent
     * @param viewType
     * @return
     */
    @Override
    public DataViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View view = LayoutInflater.from(mContext).inflate(R.layout.item,null);
        view.setOnClickListener(this);
        //使用代码设置宽高（xml布局设置无效时）
        view.setLayoutParams(new ViewGroup.LayoutParams(
                ViewGroup.LayoutParams.MATCH_PARENT,
                ViewGroup.LayoutParams.WRAP_CONTENT));
        DataViewHolder holder = new DataViewHolder(view);
        return holder;
    }

    /**
     * 绑定数据
     * @param holder
     * @param position
     */
    @Override
    public void onBindViewHolder(DataViewHolder holder, int position) {
        holder.tv_data.setText(mList.get(position));
    }

    /**
     * 选项总数
     * @return
     */
    @Override
    public int getItemCount() {
        return mList.size();
    }

    @Override
    public void onClick(View view) {
        //根据RecyclerView获得当前View的位置
        int position = recyclerView.getChildAdapterPosition(view);
        //程序执行到此，会去执行具体实现的onItemClick()方法
        if (onItemClickListener!=null){
            onItemClickListener.onItemClick(recyclerView,view,position,mList.get(position));
        }
    }

    /**
     * 创建ViewHolder
     */
    public static class DataViewHolder extends RecyclerView.ViewHolder{
        TextView tv_data;
        public DataViewHolder(View itemView) {
            super(itemView);
            tv_data = (TextView) itemView.findViewById(R.id.tv_recycle);
        }
    }

    private OnItemClickListener onItemClickListener;
    public void setOnItemClickListener(OnItemClickListener onItemClickListener){
        this.onItemClickListener = onItemClickListener;
    }

    /**
     * 定义RecyclerView选项单击事件的回调接口
     */
    public interface OnItemClickListener{
        //参数（父组件，当前单击的View,单击的View的位置，数据）
        void onItemClick(RecyclerView parent,View view, int position, String data);
    }
    /**
     *   将RecycleView附加到Adapter上
     */
    @Override
    public void onAttachedToRecyclerView(RecyclerView recyclerView) {
        super.onAttachedToRecyclerView(recyclerView);
        this.recyclerView= recyclerView;
    }
    /**
     *   将RecycleView从Adapter解除
     */
    @Override
    public void onDetachedFromRecyclerView(RecyclerView recyclerView) {
        super.onDetachedFromRecyclerView(recyclerView);
        this.recyclerView = null;
    }
}

MainActivity

/**
 * Created by jzman on 2017/5/13 0013.
 */
public class MainActivity extends AppCompatActivity {
    private RecyclerView rv;
    RvAdapter1 adapter;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        rv = (RecyclerView) findViewById(R.id.rv);
        //设置布局管理器
//        rv.setLayoutManager(new LinearLayoutManager(this));//线性
        rv.setLayoutManager(new GridLayoutManager(this,4));//线性
//        rv.setLayoutManager(new StaggeredGridLayoutManager(4,StaggeredGridLayoutManager.VERTICAL));//线性
        adapter = new RvAdapter1(this,initData());
        adapter.setOnItemClickListener(new RvAdapter1.OnItemClickListener() {
            @Override
            public void onItemClick(RecyclerView parent, View view, int position, String data) {
                Toast.makeText(MainActivity.this, data, Toast.LENGTH_SHORT).show();
            }
        });

        rv.setAdapter(adapter);
    }