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。

对于kotlin句柄，根据Jacobs的回答单击RecyclerView答案

创建类RecyclerItemClickListener:

class RecyclerItemClickListener(context: Context, recyclerView: RecyclerView, listner: OnItemClickListener) : RecyclerView.OnItemTouchListener {

    var mGestureDetector: GestureDetector
    var mListner: OnItemClickListener
    
    interface OnItemClickListener {
        fun onItemClick(view: View, position: Int)
        fun onLongItemClick(view: View, position: Int)
    }

    init {
        this.mListner = listner
        mGestureDetector = GestureDetector(context, object : GestureDetector.SimpleOnGestureListener() {
            override fun onSingleTapUp(e: MotionEvent?): Boolean = true
            
            override fun onLongPress(e: MotionEvent?) {
                val child: View? = recyclerView.findChildViewUnder(e!!.getX(), e.getY())
                if (child != null && mListner != null) {
                    mListner.onLongItemClick(child, recyclerView.getChildAdapterPosition(child))
                }
            }
        })
    }

    override fun onTouchEvent(rv: RecyclerView, e: MotionEvent) = Unit

    override fun onInterceptTouchEvent(view: RecyclerView, e: MotionEvent): Boolean {
        val childView: View? = view.findChildViewUnder(e!!.getX(), e.getY())
        if (childView != null && mListner != null && mGestureDetector.onTouchEvent(e)) {
            mListner.onItemClick(childView, view.getChildAdapterPosition(childView))
            return true
        }
        return false
    }

    override fun onRequestDisallowInterceptTouchEvent(disallowIntercept: Boolean) = Unit

}

点击Any RecyclerView(在活动/片段内):

recyclerView.addOnItemTouchListener(
    RecyclerItemClickListener(this, recyclerView, object : RecyclerItemClickListener.OnItemClickListener {
        override fun onItemClick(view: View, position: Int) {
            // TODO catch click
        }

        override fun onLongItemClick(view: View, position: Int) {
            // TODO catch click
        }
    })
)

我知道有很多答案，但我想我也可以提供我的实现。(完整的细节可以在我回答的另一个问题中找到)。

所以，要添加一个点击监听器，你的内部ViewHolder类需要实现View.OnClickListener。这是因为你将设置一个OnClickListener到ViewHolder的构造函数的itemView参数。让我来告诉你我的意思:

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

    TextView text1, text2;

    ExampleClickViewHolder(View itemView) {
        super(itemView);

        // we do this because we want to check when an item has been clicked:
        itemView.setOnClickListener(this);

        // now, like before, we assign our View variables
        title = (TextView) itemView.findViewById(R.id.text1);
        subtitle = (TextView) itemView.findViewById(R.id.text2);
    }

    @Override
    public void onClick(View v) {
        // The user may not set a click listener for list items, in which case our listener
        // will be null, so we need to check for this
        if (mOnEntryClickListener != null) {
            mOnEntryClickListener.onEntryClick(v, getLayoutPosition());
        }
    }
}

唯一需要添加的其他东西是适配器的自定义接口和setter方法:

private OnEntryClickListener mOnEntryClickListener;

public interface OnEntryClickListener {
    void onEntryClick(View view, int position);
}

public void setOnEntryClickListener(OnEntryClickListener onEntryClickListener) {
    mOnEntryClickListener = onEntryClickListener;
}

这样，新的支持单击的适配器就完成了。

现在，让我们用它…

    ExampleClickAdapter clickAdapter = new ExampleClickAdapter(yourObjects);
    clickAdapter.setOnEntryClickListener(new ExampleClickAdapter.OnEntryClickListener() {
        @Override
        public void onEntryClick(View view, int position) {
            // stuff that will happen when a list item is clicked
        }
    });

这基本上就是设置普通适配器的方法，除了使用您创建的setter方法来控制当用户单击特定列表项时要做什么。

你也可以看看我在GitHub上做的一组关于Gist的例子:

https://gist.github.com/FarbodSalamat-Zadeh/7646564f48ee708c1582c013e1de4f07

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();
}

在Kotlin中也是如此

inner class MyViewHolder(v: View, myOnClickListener: MyOnClickListener) : RecyclerView.ViewHolder(v) {
    init {
        v.setOnClickListener { v -> myOnClickListener.onClick(v, adapterPosition) }
    }
}

override fun onCreateViewHolder(viewGroup: ViewGroup, viewType: Int): MyViewHolder {
    val view = LayoutInflater.from(viewGroup.context).inflate(R.layout.myview, viewGroup, false)
    return MyViewHolder(view, mOnClickListener)
}

inner class MyOnClickListener {
    fun onClick(view: View, position: Int) {
        val item = mList[position]
        Toast.makeText(view.context, item, Toast.LENGTH_LONG).show()
    }
}

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);
    }
 }
}