nhaarman答案的Kotlin实现:

mRecyclerView.addOnItemTouchListener(object  : RecyclerItemClickListener(this, mRecyclerView,object :RecyclerItemClickListener.OnItemClickListener{
            override fun onItemClick(view: View, position: Int) {

            }

            override fun onLongItemClick(view: View?, position: Int) {

            }
}){})

RecyclerItemClickListener.java:

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


open class RecyclerItemClickListener(context: Context, recyclerView: RecyclerView, private val mListener: OnItemClickListener?) : RecyclerView.OnItemTouchListener {

    private var mGestureDetector: GestureDetector

    interface OnItemClickListener {
        fun onItemClick(view: View, position: Int)

        fun onLongItemClick(view: View?, position: Int)
    }

    init {
        mGestureDetector = GestureDetector(context, object : GestureDetector.SimpleOnGestureListener() {
            override fun onSingleTapUp(e: MotionEvent): Boolean {
                return true
            }

            override fun onLongPress(e: MotionEvent) {
                val child = recyclerView.findChildViewUnder(e.x, e.y)
                if (child != null && mListener != null) {
                    mListener.onLongItemClick(child, recyclerView.getChildAdapterPosition(child))
                }
            }
        })
    }

    override fun onInterceptTouchEvent(view: RecyclerView, e: MotionEvent): Boolean {
        val childView = view.findChildViewUnder(e.x, e.y)
        if (childView != null && mListener != null && mGestureDetector.onTouchEvent(e)) {
            mListener.onItemClick(childView, view.getChildAdapterPosition(childView))
            return true
        }
        return false
    }

    override fun onTouchEvent(view: RecyclerView, motionEvent: MotionEvent) {}

    override fun onRequestDisallowInterceptTouchEvent(disallowIntercept: Boolean) {}
}

这里有一个简单明了的方法是添加到您的ReacyclerView ViewHolder

public static class MyViewholder extends RecyclerView.ViewHolder {

    public MyViewholder(View itemView) {
        super(itemView);

        itemView.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                Log.d("Tag", "onClick：" + getAdapterPosition());
            }
        });

    }
}

getAdapterPosition()返回当前被单击项的位置

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。

将类标记为抽象并实现OnClick方法

public abstract class MainGridAdapter extends
    RecyclerView.Adapter<MainGridAdapter.ViewHolder> {
private List<MainListItem> mDataset;

// Provide a reference to the views for each data item
// Complex data items may need more than one view per item, and
// you provide access to all the views for a data item in a view holder
public class ViewHolder extends RecyclerView.ViewHolder {
    // each data item is just a string in this case
    public TextView txtHeader;
    public TextView txtFooter;

    public ViewHolder(View v) {
        super(v);
        txtHeader = (TextView) v.findViewById(R.id.firstLine);
        txtFooter = (TextView) v.findViewById(R.id.secondLine);
    }
}

public void add(int position, MainListItem item) {
    mDataset.add(position, item);
    notifyItemInserted(position);
}

public void remove(MainListItem item) {
    int position = mDataset.indexOf(item);
    mDataset.remove(position);
    notifyItemRemoved(position);
}

// Provide a suitable constructor (depends on the kind of dataset)
public MainGridAdapter(List<MainListItem> myDataset) {
    mDataset = myDataset;
}

// Create new views (invoked by the layout manager)
@Override
public MainGridAdapter.ViewHolder onCreateViewHolder(ViewGroup parent,
        int viewType) {
    // create a new view
    View v = LayoutInflater.from(parent.getContext()).inflate(
            R.layout.list_item_grid_line, parent, false);
    // set the view's size, margins, paddings and layout parameters
    ViewHolder vh = new ViewHolder(v);
    return vh;
}

// Replace the contents of a view (invoked by the layout manager)
@Override
public void onBindViewHolder(final ViewHolder holder, final int position) {
    // - get element from your dataset at this position
    // - replace the contents of the view with that element     
    OnClickListener clickListener = new OnClickListener() {
        @Override
        public void onClick(View v) {
            onItemClicked(position);
        }
    };
    holder.itemView.setOnClickListener(clickListener);
    holder.txtHeader.setOnClickListener(clickListener);
    holder.txtFooter.setOnClickListener(clickListener);
    final MainListItem item = mDataset.get(position);
    holder.txtHeader.setText(item.getTitle());
    if (TextUtils.isEmpty(item.getDescription())) {
        holder.txtFooter.setVisibility(View.GONE);
    } else {
        holder.txtFooter.setVisibility(View.VISIBLE);
        holder.txtFooter.setText(item.getDescription());
    }
}

// Return the size of your dataset (invoked by the layout manager)
@Override
public int getItemCount() {
    return mDataset.size();
}

public abstract void onItemClicked(int position);

}

在绑定事件中实现单击处理程序，使其只有一个事件实现

执行此:

mAdapter = new MainGridAdapter(listItems) {         
    @Override
    public void onItemClicked(int position) {
        showToast("Item Clicked: " + position, ToastPlus.STYLE_INFO);
    }
};

同样可以做长时间点击

这里有一个策略，它给出了一个类似于ListView实现的结果，因为你可以在活动或片段级别而不是适配器或ViewHolder级别定义侦听器。它还定义了一些抽象类，这些抽象类负责适配器和持有者的大量样板工作。

抽象类

首先，定义一个抽象Holder，它扩展了RecyclerView。并定义了一个泛型数据类型T，用于将数据绑定到视图。bindViews方法将由一个子类实现，用于将数据映射到视图。

public abstract class Holder<T> extends RecyclerView.ViewHolder {
    T data;

    public Holder(View itemView) {
        super(itemView);
    }

    public void bindData(T data){
        this.data = data;
        bindViews(data);
    }

    abstract protected void bindViews(T data);
}

同样，创建一个抽象适配器，扩展RecyclerView.Adapter<Holder<T>>。这定义了3个接口方法中的2个，子类将需要实现最后一个onViewHolderCreated方法。

public abstract class Adapter<T> extends RecyclerView.Adapter<Holder<T>> {
    List<T> list = new ArrayList<>();

    @Override
    public void onBindViewHolder(Holder<T> holder, int position) {
        holder.bindData(list.get(position));
    }

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

    public T getItem(int adapterPosition){
        return list.get(adapterPosition);
    }
}

具体类

现在创建一个扩展Holder的新具体类。该方法只需定义视图并处理绑定。这里我使用ButterKnife库，但请随意使用itemView.findViewById(…)方法代替。

public class PersonHolder extends Holder<Person>{
    @Bind(R.id.firstname) TextView firstname;
    @Bind(R.id.lastname) TextView lastname;

    public PersonHolder(View view){
        super(view);
        ButterKnife.bind(this, view);
    }

    @Override
    protected void bindViews(Person person) {
        firstname.setText(person.firstname);
        lastname.setText(person.lastname);
    }
}

最后，在持有RecyclerView的Activity或Fragment类中，你会有这样的代码:

// Create adapter, this happens in parent Activity or Fragment of RecyclerView
adapter = new Adapter<Person>(){
    @Override
    public PersonHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View v = LayoutInflater.from(parent.getContext())
                    .inflate(R.layout.layout_person_view, parent, false);

        PersonHolder holder = new PersonHolder(v);
        v.setOnClickListener(new OnClickListener(){
            @Override
            public void onClick(View v) {
                int itemPos = holder.getAdapterPosition();
                Person person = getItem(itemPos);

                // do something with person
                EventBus.getDefault().postSticky(new PersonClickedEvent(itemPos, person));
            }
        });

        return holder;
    }
};

很简单，添加这个类:

public class OnItemClickListener implements View.OnClickListener {
    private int position;
    private OnItemClickCallback onItemClickCallback;

    public OnItemClickListener(int position, OnItemClickCallback onItemClickCallback) {
        this.position = position;
        this.onItemClickCallback = onItemClickCallback;
    }

    @Override
    public void onClick(View view) {
        onItemClickCallback.onItemClicked(view, position);
    }

    public interface OnItemClickCallback {
        void onItemClicked(View view, int position);
    }
}

获取一个'OnItemClickCallback'接口实例，并把它放在你的activity或fragment中:

private OnItemClickListener.OnItemClickCallback onItemClickCallback = new OnItemClickListener.OnItemClickCallback() {
    @Override
    public void onItemClicked(View view, int position) {
    }
};

然后，将这个回调传递给你的recyclerView:

recyclerView.setAdapter(new SimpleStringRecyclerViewAdapter(Arrays.asList("1", "2", "3"), onItemClickCallback));

最后，这将是你的适配器:

public class SimpleStringRecyclerViewAdapter extends RecyclerView.Adapter<SimpleStringRecyclerViewAdapter.ViewHolder> {
    private List<String> mValues;
    private OnItemClickListener.OnItemClickCallback onItemClickCallback;

    public SimpleStringRecyclerViewAdapter(List<String> items, OnItemClickListener.OnItemClickCallback onItemClickCallback) {
        mValues = items;
        this.onItemClickCallback = onItemClickCallback;
    }

    public static class ViewHolder extends RecyclerView.ViewHolder {
        public final TextView mTextView;

        public ViewHolder(View view) {
            super(view);
            mTextView = (TextView) view.findViewById(R.id.txt_title);
        }
    }

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

    @Override
    public void onBindViewHolder(final ViewHolder holder, final int position) {
        holder.mTextView.setText(mValues.get(position));
        holder.mTextView.setOnClickListener(new OnItemClickListener(position, onItemClickCallback));
    }

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