我正在探索RecyclerView,我很惊讶地看到,RecyclerView没有onItemClickListener()。

我有两个问题。

主要问题

我想知道为什么谷歌删除onItemClickListener()?

是否存在性能问题或其他问题?

次要的问题

我解决了我的问题写onClick在我的RecyclerView。适配器:

public static class ViewHolder extends RecyclerView.ViewHolder implements OnClickListener {

    public TextView txtViewTitle;
    public ImageView imgViewIcon;

    public ViewHolder(View itemLayoutView) {
        super(itemLayoutView);
        txtViewTitle = (TextView) itemLayoutView.findViewById(R.id.item_title);
        imgViewIcon = (ImageView) itemLayoutView.findViewById(R.id.item_icon);
    }

    @Override
    public void onClick(View v) {

    }
}

这样可以吗/有更好的办法吗?


当前回答

据我所知,MLProgrammer-CiM的答案很简单,可以这样做:

class MyViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener{
    private ImageView image;
    private TextView title;
    private TextView price;

    public MyViewHolder(View itemView) {
        super(itemView);
        image = (ImageView)itemView.findViewById(R.id.horizontal_list_image);
        title = (TextView)itemView.findViewById(R.id.horizontal_list_title);
        price = (TextView)itemView.findViewById(R.id.horizontal_list_price);
        image.setOnClickListener(this);
        title.setOnClickListener(this);
        price.setOnClickListener(this);
    }


    @Override
    public void onClick(View v) {
        Toast.makeText(context, "Item click nr: "+getLayoutPosition(), Toast.LENGTH_SHORT).show();
    }
}

其他回答

我用这个方法从RecyclerView开始一个Intent:

@Override
 public void onBindViewHolder(ViewHolder viewHolder, int i) {

    final MyClass myClass = mList.get(i);
    viewHolder.txtViewTitle.setText(myclass.name);
   ...
    viewHolder.itemView.setOnClickListener(new View.OnClickListener() {
      @Override
       public void onClick(View v){
             Intent detailIntent = new Intent(mContext, type.class);                                                            
             detailIntent.putExtra("MyClass", myclass);
             mContext.startActivity(detailIntent);
       }
}
);

我喜欢这样,我正在用它

内部

public Adapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType)

Put

View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.view_image_and_text, parent, false);
v.setOnClickListener(new MyOnClickListener());

在任何你想要的地方创建这个类

class MyOnClickListener implements View.OnClickListener {
    @Override
    public void onClick(View v) {
       int itemPosition = recyclerView.indexOfChild(v);
       Log.e("Clicked and Position is ",String.valueOf(itemPosition));
    }
}

我以前读过有一个更好的方法,但我喜欢这个方法,简单,不复杂。

感谢@marmor,我更新了我的答案。

我认为在ViewHolder类构造函数中处理onClick()并通过OnItemClickListener接口将其传递给父类是一个很好的解决方案。

MyAdapter.java

public class MyAdapter extends RecyclerView.Adapter<MyAdapter.ViewHolder>{

private LayoutInflater layoutInflater;
private List<MyObject> items;
private AdapterView.OnItemClickListener onItemClickListener;

public MyAdapter(Context context, AdapterView.OnItemClickListener onItemClickListener, List<MyObject> items) {
    layoutInflater = LayoutInflater.from(context);
    this.items = items;
    this.onItemClickListener = onItemClickListener;
}

@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    View view = layoutInflater.inflate(R.layout.my_row_layout, parent, false);
    return new ViewHolder(view);
}

@Override
public void onBindViewHolder(ViewHolder holder, int position) {
    MyObject item = items.get(position);
}

public MyObject getItem(int position) {
    return items.get(position);
}


class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
    private TextView title;
    private ImageView avatar;

    public ViewHolder(View itemView) {
        super(itemView);
        title = itemView.findViewById(R.id.title);
        avatar = itemView.findViewById(R.id.avatar);

        title.setOnClickListener(this);
        avatar.setOnClickListener(this);
        itemView.setOnClickListener(this);
    }

    @Override
    public void onClick(View view) {
        //passing the clicked position to the parent class
        onItemClickListener.onItemClick(null, view, getAdapterPosition(), view.getId());
    }
}
}

适配器在其他类中的使用:

MyFragment.java

public class MyFragment extends Fragment implements AdapterView.OnItemClickListener {

private RecyclerView recycleview;
private MyAdapter adapter;

    .
    .
    .

private void init(Context context) {
    //passing this fragment as OnItemClickListener to the adapter
    adapter = new MyAdapter(context, this, items);
    recycleview.setAdapter(adapter);
}

@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
    //you can get the clicked item from the adapter using its position
    MyObject item = adapter.getItem(position);

    //you can also find out which view was clicked
    switch (view.getId()) {
        case R.id.title:
            //title view was clicked
            break;
        case R.id.avatar:
            //avatar view was clicked
            break;
        default:
            //the whole row was clicked
    }
}

}

看看我的方法:

首先像这样声明一个接口:

/**
 * Interface used for delegating item click events in a {@link android.support.v7.widget.RecyclerView}
 * Created by Alex on 11/28/2015.
 */
  public interface OnRecyclerItemClickListener<T> {

     /**
      * Called when a click occurred inside a recyclerView item view
      * @param view that was clicked
      * @param position of the clicked view
      * @param item the concrete data that is displayed through the clicked view
      */
      void onItemClick(View view, int position, T item);
   }

然后创建适配器:

public class CustomRecyclerAdapter extends RecyclerView.Adapter {      

    private class InternalClickListener implements View.OnClickListener{

      @Override
      public void onClick(View v) {
        if(mRecyclerView != null && mItemClickListener != null){
            // find the position of the item that was clicked
            int position = mRecyclerView.getChildAdapterPosition(v);
            Data data = getItem(position);
            // notify the main listener
            mItemClickListener.onItemClick(v, position, data);
        }
    }
}

private final OnRecyclerItemClickListener mItemClickListener;
private RecyclerView mRecyclerView;    
private InternalClickListener mInternalClickListener;


/**
 *
 * @param itemClickListener used to trigger an item click event
 */
public PlayerListRecyclerAdapter(OnRecyclerItemClickListener itemClickListener){        
    mItemClickListener = itemClickListener;
    mInternalClickListener = new InternalClickListener();
}

@Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
   View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.recycler_item, parent, false);

    v.setOnClickListener(mInternalClickListener);

    ViewHolder viewHolder = new ViewHolder(v);
    return viewHolder;
}

@Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
    // do your binding here
}

@Override
public int getItemCount() {
    return mDataSet.size();
}

@Override
public void onAttachedToRecyclerView(RecyclerView recyclerView) {
    super.onAttachedToRecyclerView(recyclerView);

    mRecyclerView = recyclerView;
}

@Override
public void onDetachedFromRecyclerView(RecyclerView recyclerView) {
    super.onDetachedFromRecyclerView(recyclerView);

    mRecyclerView = null;
}

public Data getItem(int position){
    return mDataset.get(position);
}
}

现在让我们看看如何从一个片段中整合这个:

public class TestFragment extends Fragment implements OnRecyclerItemClickListener<Data>{
   private RecyclerView mRecyclerView;

   @Override
   public void onItemClick(View view, int position, Data item) {
     // do something
   }

   @Override
   public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
      return inflater.inflate(R.layout.test_fragment, container, false);
   }

   @Override
   public void onViewCreated(View view, Bundle savedInstanceState) {
      mRecyclerView = view.findViewById(idOfTheRecycler);
      mRecyclerView .setAdapter(new CustomRecyclerAdapter(this));
   }

如果你想添加onClick()到项目的子视图,例如,项目中的按钮,我发现你可以很容易地在你自己的RecyclerView的onCreateViewHolder()中做到这一点。适配器就像这样:

        @Override
        public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
            View v = LayoutInflater
                    .from(parent.getContext())
                    .inflate(R.layout.cell, null);

            Button btn = (Button) v.findViewById(R.id.btn);
            btn.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    //do it
                }
            });

            return new MyViewHolder(v);
        }

我不知道这是不是一个好方法,但它很有效。如果有人有更好的想法,很高兴告诉我并纠正我的答案!:)