我正在使用一个Android应用程序,该应用程序从服务器下载图像并将其显示在Recycler视图中。
我在为每个图像启用onclick时遇到问题。

在我的MyRecyclerViewAdapterClass中:

public class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
    public TextView myTextView;
    public ImageView myImage;

    ViewHolder(View itemView) {
        super(itemView);
        myTextView = (TextView) itemView.findViewById(R.id.info_text);
        myImage = (ImageView) itemView.findViewById(R.id.image_test);
        itemView.setOnClickListener(this);
    }

    @Override
    public void onClick(View view) {
        if (mClickListener != null) mClickListener.onItemClick(view, getAdapterPosition());
    }
}

    void setClickListener(ItemClickListener itemClickListener) {
        this.mClickListener = itemClickListener;
    }

    public interface ItemClickListener {
        void onItemClick(View view, int position);
    }

    String getItem(int id){
        return mData[id];
    }
    public void onItemClick(View view, int position){
        Log.i("TAG","You clicked number" + getItem(position));
}


在我的主要活动中:

public void postImage() {
    runOnUiThread(new Runnable() {
        @Override
        public void run() {

            //RecyclerView.
            RecyclerView recyclerView = (RecyclerView) findViewById(R.id.rvNumbers);
            recyclerView.setLayoutManager(new GridLayoutManager(context, numberOfColumns));
            MyRecyclerViewAdapter.ItemClickListener itemClickListener;
            adapter = new MyRecyclerViewAdapter(context,data,file_payload);

            **adapter.setClickListener(this);**
            adapter.mData = data;
            adapter.PAYLOADS = allPayloads;
            adapter.DATES = allDates;
            recyclerView.setAdapter(adapter);

        }
    });}


当我调用adapter.setListener(this)时出现错误:


  我的RecyclerView中的setClickListener无法应用,
  onymous.java.lang.Runnable


我尝试在代码中看到在runnable中创建一个itemClickListener,并将其用于调用adaptersetClickListener(itemClickListener),但是由于未初始化itemClickListener,因此出现错误。

如果我不调用setClickListener方法,则不会设置mClickListener,并且始终为null。调试时,我注意到该点击已注册,但因为mClickListener为null而没有任何反应。

最佳答案

当我调用adapter.setListener(this)时出现错误:


因为这里this表示您实现的Runnable实例,并且正在适配器中传递Runnable实例而不是MyRecyclerViewAdapter.ItemClickListener

我认为您正在尝试将MyRecyclerViewAdapter.ItemClickListener实例传递给ViewHolder。如果我是对的,

为了那个原因:


您必须在MainActivity中实现MyRecyclerViewAdapter.ItemClickListener
将该实例传递给Adapter
然后从Adapter将该实例传递给ViewHolder


在MainActivity中:

MyRecyclerViewAdapter.ItemClickListener listener = new MyRecyclerViewAdapter.ItemClickListener() {
  @Override
  public void onItemClick(View view, int position) {
     Log.i("TAG","You clicked number" + position);
  }
};

adapter = new MyRecyclerViewAdapter(context,data,file_payload);
adapter. setItemClickListener( listener);


在适配器中

public interface ItemClickListener {
    void onItemClick(View view, int position);
 }

ItemClickListener listener;

public void setItemClickListener(ItemClickListener listener){
   this.listener = listener;
}

@Override
 public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    View v = LayoutInflater.from(parent.getContext()).inflate(itemLayout, parent, false);
    ViewHolder viewHolder =  new ViewHolder(v);
    viewHolder.setItemClickListener(listener);
    return viewHolder;
 }


在您的ViewHolder中:

public class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
public TextView myTextView;
public ImageView myImage;
MyRecyclerViewAdapter.ItemClickListener itemClickListener;

ViewHolder(View itemView) {
    super(itemView);
    myTextView = (TextView) itemView.findViewById(R.id.info_text);
    myImage = (ImageView) itemView.findViewById(R.id.image_test);
    itemView.setOnClickListener(this);
}

@Override
public void onClick(View view) {
    if (itemClickListener != null) itemClickListener.onItemClick(view, getAdapterPosition());
 }


void setItemClickListener(MyRecyclerViewAdapter.ItemClickListener itemClickListener) {
    this.itemClickListener = itemClickListener;
 }


  String getItem(int id){
    return mData[id];
   }
}

09-28 01:08