在RecyclerView上获取对ViewHolder的引用单击

Question

这是我第一次尝试实施RecyclerView。我在Callback和Adapter类之间实现了ViewHolder接口，以处理UI元素（按钮）上的Click事件。我在获取点击发生的ViewHolder时遇到问题。我可以点击列表中第一个项目的Button，但是我定义的操作是在最后一个上执行的我的回收站视图中的viewholder。我终于想通过我的界面传递这个位置，但是我很难理解如何从中获取对该视图的引用。

    public class RoomAdapter extends RecyclerView.Adapter<RoomAdapter.RoomViewHolder>
{
    List<Room> mRooms;
    public RoomAdapter(List<Room> rooms) {
        mRooms = rooms;
    }

    @Override
    public RoomViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
        final View viewItem = LayoutInflater
                .from(viewGroup.getContext())
                .inflate(R.layout.room_rv_item,viewGroup,false);
        return vh = new RoomViewHolder(viewItem,new IRoomViewClick() {
            @Override
            public void editname(int pos) {

            }
        });
    }

    @Override
    public void onBindViewHolder(RoomViewHolder roomViewHolder, int i) {
        Room r = getItem(i);
        roomViewHolder.label.setText(r.name);


    }
    public Room getItem(int position)
    {
        return mRooms.get(position);
    }
    @Override
    public long getItemId(int position) {
        return mRooms.get(position).getId();
    }

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

    public static class RoomViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener
    {
        TextView label;
        Button editBtn;
        LinearLayout labelView;
        Button saveBtn;
        Button deleteBtn;
        EditText editNameET;
        IRoomViewClick mListener;
        public RoomViewHolder(View itemView, IRoomViewClick listener) {
            super(itemView);
            labelView = (LinearLayout) itemView.findViewById(R.id.labelview);
            mListener = listener;
            editBtn =(Button) itemView.findViewById(R.id.editbtn);
            editBtn.setOnClickListener(this);
            label = (TextView) itemView.findViewById(R.id.room_listitem_label);

        }

        @Override
        public void onClick(View view) {
            int pos = getPosition();
            mListener.editname(pos);



        }
    }
    public static interface IRoomViewClick
    {
        public void editname(int pos);
    }

}

Answer 1

您可以在editBtn中为onBindViewHolder设置标记：

    public RoomViewHolder(View itemView, IRoomViewClick listener) {
        ....
        editBtn =(Button) itemView.findViewById(R.id.editbtn);
        //add tag for this view
        editBtn.setTag(this);
        ....
   }

并在onClick

中获取

    @Override
    public void onClick(View view) {
        //getTag
        RoomViewHolder holder = (RoomViewHolder )(view.getTag());
        int pos = getPosition();
        mListener.editname(pos);
    ...
    }

Answer 2

实际上，通过在RecyclerView上调用getTag，您可以做得比getChildViewHolder(View child)更好：

@Override
public void onClick(View v) {
    MyHolder holder = (MyHolder) mRecyclerView.getChildViewHolder(v);
    holder.textView.setText("Clicked!");
}

Answer 3

@Override
public void onClick(View v) {
    int pos = getAdapterPosition(); //getPosition() is deprecated 
    notifyItemChanged(pos);
}

notifyItemChanged会通知你的onBindViewHolder，然后你可以做这样的事情

public void onBindViewHolder(RoomViewHolder roomViewHolder, int i) {
    Room r = getItem(i);
    roomViewHolder.label.setText(r.name);
    if(i == pos){ // Do Something }

}

每当您点击该项目时，它都会改变pos＆＃39;值并触发// Do Something

Answer 4

证明RecycleView将视图位置保存在视图布局参数中，因此如果您只想让视图位置从列表中获取正确的项目，则可以使用此项：

RecyclerView.LayoutParams lp = (RecyclerView.LayoutParams) v.getLayoutParams();
lp.getViewPosition();