在kotlin中使用构造函数实现

初始化你的RecyclerView构造函数，如下所示:

class ListAdapter(
    c: Context,
    private var list: List<Project>,
    private val itemClick: (Project) -> Unit
) : RecyclerView.Adapter<ListAdapter.ViewHolder>() 

在onCreateViewHolder中使用itemClick返回:

override fun onCreateViewHolder(parent: ViewGroup, viewType: Int):ProjectViewHolder {
    val view = inflater.inflate(R.layout.list_item, parent, false)
    return ViewHolder(view, itemClick)
}

你的onBindViewHolder:

override fun onBindViewHolder(holder: ViewHolder, position: Int) {
    holder.bindProject(list[position])
}

然后用ViewHolder类创建bindProject函数。

class ViewHolder(
    view: View,
    private val itemClick: (Project) -> Unit
) : RecyclerView.ViewHolder(view) {

    private val clientTextCount = 7

    val titleTextView: TextView = view.projectTitleTextView
 
    fun bindProject(project: Project) {
        with(project) {
            titleTextView.text = name
            itemView.setOnClickListener { itemClick(this) }
        }
    }
}

最后在您的活动中用lazy初始化适配器

private val adapter: ListAdapter by lazy {
    ListAdapter(this, projectList, {
        // Here you can implement your onClick function.
    })
}

在适配器中为RecyclerView添加新列表初始化以下方法:

fun setProjects(projects: List<Project>) {
    projectList = projects
    notifyDataSetChanged()
}

在你的活动中调用setProjects方法:

adapter.setProjects(projects)

就是这样。

由于API已经发生了根本性的变化，如果你要为每个项目创建一个OnClickListener，这不会让我感到惊讶。不过也没那么麻烦。在你的RecyclerView的实现中。适配器<MyViewHolder>，你应该有:

private final OnClickListener mOnClickListener = new MyOnClickListener();

@Override
public MyViewHolder onCreateViewHolder(final ViewGroup parent, final int viewType) {
    View view = LayoutInflater.from(mContext).inflate(R.layout.myview, parent, false);
    view.setOnClickListener(mOnClickListener);
    return new MyViewHolder(view);
}

onClick方法:

@Override
public void onClick(final View view) {
    int itemPosition = mRecyclerView.getChildLayoutPosition(view);
    String item = mList.get(itemPosition);
    Toast.makeText(mContext, item, Toast.LENGTH_LONG).show();
}

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){}
}

查看类似的问题@CommonsWare的评论链接到this，它在viewHolder中实现了OnClickListener接口。

下面是ViewHolder的一个简单例子:

/** Declare global with in adapter class. */
TextView textView;

public static class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {

    private ViewHolder(View itemView) {
        super(itemView);
        itemView.setOnClickListener(this);
        textView = (TextView) view.findViewById(android.R.id.text1);   
    }

    @Override
    public void onClick(View view) {
        Toast.makeText(view.getContext(), "position = " + getLayoutPosition(), Toast.LENGTH_SHORT).show();
         
        /** Go through each item if you have few items within RecyclerView. */
        if (getLayoutPosition() == 0) {
           // Do whatever you want here
        } else if(getLayoutPosition() == 1) { 
           // Do whatever you want here
        } else if(getLayoutPosition() == 2) {
           // Do whatever you want here
        }

        /** Or you can use For loop if you have long list of items. */
        for (int i = 0; i < exampleList.size(); i++) {
            // Do whatever you want here
        }
    }
}

在你的RecyclerView中创建ViewHolder。适配器看起来像这样:

@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    LayoutInflater inflater = LayoutInflater.from(parent.getContext())
    View view = inflater.inflate(android.R.layout.simple_list_item_1, parent, false);
    return new ViewHolder(view);
}

如果你想在个别项目上捕捉点击事件，那么只需在ViewHolder类中实现OnClickListener，然后在个别视图或整个itemView上设置点击侦听器。

下面的例子说明了同样的情况

public  class ContactViewHolder extends RecyclerView.ViewHolder implements OnClickListener
    {
        TextView txt_title,txt_name,txt_email;

        public ContactViewHolder(View itemView) 
        {
            super(itemView);
            txt_title = (TextView)itemView.findViewById(R.id.txt_title);
            txt_name  = (TextView)itemView.findViewById(R.id.txt_name);
            txt_email = (TextView)itemView.findViewById(R.id.txt_email);

            txt_name.setOnClickListener(this);
            txt_email.setOnClickListener(this);
            itemView.setOnClickListener(this);
        }

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub

            if(v == itemView)
            {
                Toast.makeText(RecyclerDemoActivity.this, "Visiting Card Clicked is ==>"+txt_name.getText(), Toast.LENGTH_SHORT).show();
            }

            if(v == txt_name)
            {
                Toast.makeText(RecyclerDemoActivity.this, "Name ==>"+txt_name.getText(), Toast.LENGTH_SHORT).show();
            }

            if(v == txt_email)
            {
                Toast.makeText(RecyclerDemoActivity.this, "Email ==>"+txt_email.getText(), Toast.LENGTH_SHORT).show();
            }
        }

    }
} 

以下是我所做的。这个解决方案同时支持onClick和onLongClick在两个RecyclerView项目和视图内的RecyclerView项目(内部视图)。

我在我选择的视图上标记viewHolder:

public RecyclerViewAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    View itemView = LayoutInflater.from(parent.getContext()).inflate(R.layout.layout_item, null);
    ViewHolder viewHolder = new ViewHolder(itemView);

    itemView.setOnClickListener( this);
    itemView.setOnLongClickListener(this);
    viewHolder.imageIV.setOnClickListener(this);
    viewHolder.imageIV.setOnLongClickListener(this);

    viewHolder.imageIV.setTag(viewHolder);
    itemView.setTag(viewHolder);

    return viewHolder;
}

我使用holder.getPosition()在onClick()方法中检索位置(onLongClick类似):

public void onClick(View view) {
    ViewHolder holder = (ViewHolder) view.getTag();
    int position = holder.getPosition();

    if (view.getId() == holder.imageIV.getId()){
        Toast.makeText(context, "imageIV onClick at" + position, Toast.LENGTH_SHORT).show();
    } else {
        Toast.makeText(context, "RecyclerView Item onClick at " + position, Toast.LENGTH_SHORT).show();
    }
}

带有getChildPosition的变体也可以工作。请注意，对于内部视图，在onClick()中使用:

int position = recyclerView.getChildPosition((View)view.getParent());

在我看来，这个解决方案的优点是，当一个人点击图像，只有onclick()图像侦听器被调用，而当我结合Jacob的解决方案为一个RecyclerView项目视图和我的解决方案为内部视图的RecyclerView项目视图onclick()也被调用(当点击图像)。