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

修改了我的评论…

public class MyViewHolder extends RecyclerView.ViewHolder {

        private Context mContext;

        public MyViewHolder(View itemView) {
            super(itemView);

            mContext = itemView.getContext();

            itemView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View view) {

                    int itemPosition = getLayoutPosition();
                    Toast.makeText(mContext, "" + itemPosition, Toast.LENGTH_SHORT).show();

                }
            });
        }

其他回答

 main_recyclerview.addOnItemTouchListener(new RecyclerView.OnItemTouchListener() {
        @Override
        public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent e)
        {
            int position=rv.getChildAdapterPosition(rv.findChildViewUnder(e.getX(),e.getY()));

            switch (position)
            {
                case 0:
                {
                    wifi(position);
                    adapter2.notifyDataSetChanged();
                }
                break;

                case 1:
                {
                    sound(position);
                    adapter2.notifyDataSetChanged();
                }
                break;

                case 2:
                {
                    bluetooth(position);
                    adapter2.notifyDataSetChanged();
                }
                break;


            }
            return true;
        }

        @Override
        public void onTouchEvent(RecyclerView rv, MotionEvent e)
        {

        }

        @Override
        public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) {

        }
    });

使用RxJava和PublishSubject为点击公开一个Observable。

public class ReactiveAdapter extends RecyclerView.Adapter<MyAdapter.ViewHolder> {
    String[] mDataset = { "Data", "In", "Adapter" };

    private final PublishSubject<String> onClickSubject = PublishSubject.create();

    @Override 
    public void onBindViewHolder(final ViewHolder holder, int position) {
        final String element = mDataset[position];

        holder.itemView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
               onClickSubject.onNext(element);
            }
        });
    }

    public Observable<String> getPositionClicks(){
        return onClickSubject.asObservable();
    }
}

原来的帖子:

自从ListView的引入,onItemClickListener就一直存在问题。当你有一个内部元素的点击监听器时,回调不会被触发,但它没有被通知或良好的记录(如果有的话),所以有很多困惑和so问题。

考虑到RecyclerView更进一步,没有行/列的概念,而是任意布局的子节点数量,他们将onClick委托给每个子节点,或者委托给程序员实现。

不要认为Recyclerview是ListView的1:1替代品,而是一个更灵活的组件,用于复杂的用例。正如你所说,你的解决方案是谷歌对你的期望。现在您有了一个适配器,它可以将onClick委托给传递给构造函数的接口,这对于ListView和Recyclerview来说都是正确的模式。

public static class ViewHolder extends RecyclerView.ViewHolder implements OnClickListener {

    public TextView txtViewTitle;
    public ImageView imgViewIcon;
    public IMyViewHolderClicks mListener;

    public ViewHolder(View itemLayoutView, IMyViewHolderClicks listener) {
        super(itemLayoutView);
        mListener = listener;
        txtViewTitle = (TextView) itemLayoutView.findViewById(R.id.item_title);
        imgViewIcon = (ImageView) itemLayoutView.findViewById(R.id.item_icon);
        imgViewIcon.setOnClickListener(this);
        itemLayoutView.setOnClickListener(this);
    }

    @Override
    public void onClick(View v) {
        if (v instanceof ImageView){
           mListener.onTomato((ImageView)v);
        } else {
           mListener.onPotato(v);
        }
    }

    public static interface IMyViewHolderClicks {
        public void onPotato(View caller);
        public void onTomato(ImageView callerImage);
    }

}

然后在适配器上

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

   String[] mDataset = { "Data" };

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

       MyAdapter.ViewHolder vh = new ViewHolder(v, new MyAdapter.ViewHolder.IMyViewHolderClicks() { 
           public void onPotato(View caller) { Log.d("VEGETABLES", "Poh-tah-tos"); };
           public void onTomato(ImageView callerImage) { Log.d("VEGETABLES", "To-m8-tohs"); }
        });
        return vh;
    }

    // Replace the contents of a view (invoked by the layout manager) 
    @Override 
    public void onBindViewHolder(ViewHolder holder, int position) {
        // Get element from your dataset at this position 
        // Replace the contents of the view with that element 
        // Clear the ones that won't be used
        holder.txtViewTitle.setText(mDataset[position]);
    } 

    // Return the size of your dataset (invoked by the layout manager) 
    @Override 
    public int getItemCount() { 
        return mDataset.length;
    } 
  ...

Now look into that last piece of code: onCreateViewHolder(ViewGroup parent, int viewType) the signature already suggest different view types. For each one of them you'll require a different viewholder too, and subsequently each one of them can have a different set of clicks. Or you can just create a generic viewholder that takes any view and one onClickListener and applies accordingly. Or delegate up one level to the orchestrator so several fragments/activities have the same list with different click behaviour. Again, all flexibility is on your side.

它是一个非常需要的组件,非常接近我们的内部实现和到目前为止对ListView的改进。谷歌终于承认了这一点,这很好。

访问rowLayout(cell)的mainView为你的RecyclerView和在你的OnBindViewHolder写以下代码:

    @Override
    public void onBindViewHolder(MyViewHolder holder, final int position) {
        Movie movie = moviesList.get(position);
        holder.mainView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                System.out.println("pos " + position);
            }
        });
    }

我是这么做的,很简单:

只需为Clicked RecyclerView位置添加一行:

int position = getLayoutPosition()

ViewHolder类的完整代码:

private class ChildViewHolder extends RecyclerView.ViewHolder {
        public ImageView imageView;
        public TextView txtView;

        public ChildViewHolder(View itemView) {
            super(itemView);
            imageView= (ImageView)itemView.findViewById(R.id.imageView);
            txtView= (TextView) itemView.findViewById(R.id.txtView);
            itemView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View view) {
                    Log.i("RecyclerView Item Click Position", String.valueOf(getLayoutPosition()));
                }
            });
        }
    }

希望这对你有所帮助。

跟进MLProgrammer-CiM的优秀RxJava解决方案

消费/观察点击

Consumer<String> mClickConsumer = new Consumer<String>() {
        @Override
        public void accept(@NonNull String element) throws Exception {
            Toast.makeText(getApplicationContext(), element +" was clicked", Toast.LENGTH_LONG).show();
        }
    };

ReactiveAdapter rxAdapter = new ReactiveAdapter();
rxAdapter.getPositionClicks().subscribe(mClickConsumer);

RxJava 2.+

将原tl;dr修改为:

public Observable<String> getPositionClicks(){
    return onClickSubject;
}

PublishSubject#asObservable()被移除。只需要返回PublishSubject,它是一个可观察对象。