让我们看看如何在Jetpack / AndroidX中实现这一点

你需要像这样在viewmodel类中创建一个观察对象

private MutableLiveData<Integer> adapterItem = new MutableLiveData<>();

public MutableLiveData<Integer> getAdapterItem() {
    return adapterItem;
}

public void setAdapterItem(int adapterItem) {
    this.getAdapterItem().setValue(adapterItem);
}

然后在适配器类中，确保将viewmodel引用作为构造函数的参数传递，然后在vieholder上实现clicklistener

    public MyViewHolder(@NonNull View itemView) {
        super(itemView);
        if(itemView != null){
            itemView.setOnClickListener(v -> {
                int adapterPosition = getAdapterPosition();
                viewModel.setAdapterItem(adapterPosition);
            });

        };
    }

然后从活动课上观察变化

    viewModel.getAdapterItem().observe(this, position -> {
        Log.w(TAG, "clicked: " + ridesArray.get(position));
    });

让我们看看如何在Jetpack / AndroidX中实现这一点

你需要像这样在viewmodel类中创建一个观察对象

private MutableLiveData<Integer> adapterItem = new MutableLiveData<>();

public MutableLiveData<Integer> getAdapterItem() {
    return adapterItem;
}

public void setAdapterItem(int adapterItem) {
    this.getAdapterItem().setValue(adapterItem);
}

然后在适配器类中，确保将viewmodel引用作为构造函数的参数传递，然后在vieholder上实现clicklistener

    public MyViewHolder(@NonNull View itemView) {
        super(itemView);
        if(itemView != null){
            itemView.setOnClickListener(v -> {
                int adapterPosition = getAdapterPosition();
                viewModel.setAdapterItem(adapterPosition);
            });

        };
    }

然后从活动课上观察变化

    viewModel.getAdapterItem().observe(this, position -> {
        Log.w(TAG, "clicked: " + ridesArray.get(position));
    });

这是我所做的阅读更多和下载要点在这里

在这里添加相同的内容

CustomItemClickListener.java

public interface CustomItemClickListener {
 public void onItemClick(View v, int position);
}

ItemsListAdapter.java

public class ItemsListAdapter extends RecyclerView.Adapter<ItemsListAdapter.ViewHolder> {
ArrayList<ItemListSingleItem> data;

Context mContext;
CustomItemClickListener listener;

@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    View mView = LayoutInflater.from(parent.getContext()).inflate(R.layout.items_list_single_item, parent, false);
    final ViewHolder mViewHolder = new ViewHolder(mView);
    mView.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            listener.onItemClick(v, mViewHolder.getAdapterPosition());
        }
    });
    return mViewHolder;
}

@Override
public void onBindViewHolder(ViewHolder holder, int position) {
    holder.itemTitle.setText(Html.fromHtml(data.get(position).getTitle()));
    if (!TextUtils.isEmpty(data.get(position).getThumbnailURL())) {
      // I Love picasso library :) http://square.github.io/picasso/
        Picasso.with(mContext).load(data.get(position).getThumbnailURL()).error(R.drawable.ic_no_image).
                placeholder(R.drawable.ic_no_image).
                transform(new RoundedCornersTransformation(5, 0)).
                into(holder.thumbnailImage);
    } else {
        holder.thumbnailImage.setImageResource(R.drawable.ic_no_image);
    }
}


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

public ItemsListAdapter(Context mContext, ArrayList<ItemsListSingleItem> data, CustomItemClickListener listener) {
    this.data = data;
    this.mContext = mContext;
    this.listener = listener;
}

public static class ViewHolder extends RecyclerView.ViewHolder {
    public TextView itemTitle;
    public ImageView thumbnailImage;

    ViewHolder(View v) {
        super(v);
        itemTitle = (TextView) v
                .findViewById(R.id.post_title);
        thumbnailImage = (ImageView) v.findViewById(R.id.post_thumb_image);
    }
 }
}

这对我来说很管用。将OnClickListener附加到onBindView。我真的不知道这是否会影响性能，但它似乎用很少的代码就能很好地工作。

public void onBindViewHolder(ViewHolder holder, final int position) {
    holder.view.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Toast.makeText(context, "Recycle Click" + position, Toast.LENGTH_SHORT).show();
            }
    });
}

太简单和有效了。

而不是实现接口视图。OnClickListener内的视图持有人或创建和接口和实现接口在您的活动- 我使用这段代码简单的OnClickListener实现。

public static class SimpleStringRecyclerViewAdapter
            extends RecyclerView.Adapter<SimpleStringRecyclerViewAdapter.ViewHolder> {

        // Your initializations goes here...
        private List<String> mValues;

        public static class ViewHolder extends RecyclerView.ViewHolder {

            //create a variable mView
            public final View mView;

            /*All your row widgets goes here
            public final ImageView mImageView;
            public final TextView mTextView;*/

            public ViewHolder(View view) {
                super(view);
                //Initialize it here
                mView = view;

                /* your row widgets initializations goes here
                mImageView = (ImageView) view.findViewById(R.id.avatar);
                mTextView = (TextView) view.findViewById(android.R.id.text1);*/
            }
        }

        public String getValueAt(int position) {
            return mValues.get(position);
        }

        public SimpleStringRecyclerViewAdapter(Context context, List<String> items) {

            mBackground = mTypedValue.resourceId;
            mValues = items;
        }

        @Override
        public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
            View view = LayoutInflater.from(parent.getContext())
                    .inflate(R.layout.list_item, parent, false);
            view.setBackgroundResource(mBackground);
            return new ViewHolder(view);
        }

        @Override
        public void onBindViewHolder(final ViewHolder holder, int position) {
            holder.mBoundString = mValues.get(position);
            holder.mTextView.setText(mValues.get(position));

            //Here it is simply write onItemClick listener here
            holder.mView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    Context context = v.getContext();
                    Intent intent = new Intent(context, ExampleActivity.class);

                    context.startActivity(intent);
                }
            });
        }

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

这里有一个更好的和不那么紧密耦合的方式来实现一个OnClickListener的RecyclerView。

用法片段:

RecyclerView recyclerView = findViewById(R.id.recycler);
recyclerView.addOnItemTouchListener(
    new RecyclerItemClickListener(context, recyclerView ,new RecyclerItemClickListener.OnItemClickListener() {
      @Override public void onItemClick(View view, int position) {
        // do whatever
      }

      @Override public void onLongItemClick(View view, int position) {
        // do whatever
      }
    })
);

RecyclerItemClickListener实现:

import android.content.Context;
import android.support.v7.widget.RecyclerView;
import android.view.GestureDetector;
import android.view.MotionEvent;
import android.view.View;


public class RecyclerItemClickListener implements RecyclerView.OnItemTouchListener {
  private OnItemClickListener mListener;

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

    public void onLongItemClick(View view, int position);
  }

  GestureDetector mGestureDetector;

  public RecyclerItemClickListener(Context context, final RecyclerView recyclerView, OnItemClickListener listener) {
    mListener = listener;
    mGestureDetector = new GestureDetector(context, new GestureDetector.SimpleOnGestureListener() {
        @Override
        public boolean onSingleTapUp(MotionEvent e) {
            return true;
        }

        @Override
        public void onLongPress(MotionEvent e) {
            View child = recyclerView.findChildViewUnder(e.getX(), e.getY());
            if (child != null && mListener != null) {
                mListener.onLongItemClick(child, recyclerView.getChildAdapterPosition(child));
            }
        }
    });
}

  @Override public boolean onInterceptTouchEvent(RecyclerView view, MotionEvent e) {
    View childView = view.findChildViewUnder(e.getX(), e.getY());
    if (childView != null && mListener != null && mGestureDetector.onTouchEvent(e)) {
      mListener.onItemClick(childView, view.getChildAdapterPosition(childView));
      return true;
    }
    return false;
  }

  @Override public void onTouchEvent(RecyclerView view, MotionEvent motionEvent) { }

  @Override
  public void onRequestDisallowInterceptTouchEvent (boolean disallowIntercept){}
}