有人使用RecyclerView找到了一种方法来设置一个onClickListener的项目在RecyclerView? 我想设置一个监听器为每个项目的布局,但这似乎有点太麻烦了 我确信有一种方法让RecyclerView监听onClick事件,但我不能完全弄清楚。


当前回答

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();
    }
}

其他回答

我们可以使用Java弱引用来实现这一点。 从语义上讲,视图持有者应该响应click事件或将其委托给正确的响应器。

我们的目标:

Viewholder应该对响应事件的类一无所知,除非它实现了某个接口。 点击处理程序应该得到被点击的视图在RecyclerView中的位置。 我们应该能够辨别视图持有人中单击了哪个视图。 保持所有组件之间的松散耦合,不要造成任何保留周期。

步骤:

Create an interface to handle click responses. Implement this interface in the Activity that will handle the click. Add a member variable in the RecyclerView Adapter to hold the Weak Reference and a constructor that sets it. Do the same in the RecyclerView ViewHolder and add a member variable to keep track of position. Set your on click listeners on any view you'd like in the ViewHolder, then callback to the responder to handle them. Change your onBindViewHolder method to set the position when binding. Pass the responder down to the ViewHolder. In the responder, you can now use getId() on the view to figure out which view was clicked.

这里是一个要点,这样你就可以看到它们是如何组合在一起的: RecyclerView点击处理

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();
}

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

不幸的是,RecyclerView缺少ListView内置的几个功能。 例如,添加OnItemClickListener的能力,当一个项目被单击时触发。 RecyclerView允许你在适配器中设置一个OnClickListener,但是传递那个点击 从你的调用代码,到适配器,再到ViewHolder,监听器是复杂的 要捕捉一个简单的项目单击。

public class ItemClickSupport {
private final RecyclerView mRecyclerView;
private OnItemClickListener mOnItemClickListener;
private OnItemLongClickListener mOnItemLongClickListener;
private View.OnClickListener mOnClickListener = new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        if (mOnItemClickListener != null) {
            RecyclerView.ViewHolder holder = mRecyclerView.getChildViewHolder(v);
            mOnItemClickListener.onItemClicked(mRecyclerView, holder.getAdapterPosition(), v);
        }
    }
};
private View.OnLongClickListener mOnLongClickListener = new View.OnLongClickListener() {
    @Override
    public boolean onLongClick(View v) {
        if (mOnItemLongClickListener != null) {
            RecyclerView.ViewHolder holder = mRecyclerView.getChildViewHolder(v);
            return mOnItemLongClickListener.onItemLongClicked(mRecyclerView, holder.getAdapterPosition(), v);
        }
        return false;
    }
};
private RecyclerView.OnChildAttachStateChangeListener mAttachListener
        = new RecyclerView.OnChildAttachStateChangeListener() {
    @Override
    public void onChildViewAttachedToWindow(View view) {
        if (mOnItemClickListener != null) {
            view.setOnClickListener(mOnClickListener);
        }
        if (mOnItemLongClickListener != null) {
            view.setOnLongClickListener(mOnLongClickListener);
        }
    }

    @Override
    public void onChildViewDetachedFromWindow(View view) {

    }
};

private ItemClickSupport(RecyclerView recyclerView) {
    mRecyclerView = recyclerView;
    mRecyclerView.setTag(R.id.item_click_support, this);
    mRecyclerView.addOnChildAttachStateChangeListener(mAttachListener);
}

public static ItemClickSupport addTo(RecyclerView view) {
    ItemClickSupport support = (ItemClickSupport) view.getTag(R.id.item_click_support);
    if (support == null) {
        support = new ItemClickSupport(view);
    }
    return support;
}

public static ItemClickSupport removeFrom(RecyclerView view) {
    ItemClickSupport support = (ItemClickSupport) view.getTag(R.id.item_click_support);
    if (support != null) {
        support.detach(view);
    }
    return support;
}

public ItemClickSupport setOnItemClickListener(OnItemClickListener listener) {
    mOnItemClickListener = listener;
    return this;
}

public ItemClickSupport setOnItemLongClickListener(OnItemLongClickListener listener) {
    mOnItemLongClickListener = listener;
    return this;
}

private void detach(RecyclerView view) {
    view.removeOnChildAttachStateChangeListener(mAttachListener);
    view.setTag(R.id.item_click_support, null);
}

public interface OnItemClickListener {

    void onItemClicked(RecyclerView recyclerView, int position, View v);
}

public interface OnItemLongClickListener {

    boolean onItemLongClicked(RecyclerView recyclerView, int position, View v);
}
}

您还需要定义R.id。使用ids.xml:

 <?xml version="1.0" encoding="utf-8"?>
 <resources>
  <item name="item_click_support" type="id" />
 </resources>

结果代码点击侦听器现在看起来像这样:

ItemClickSupport.addTo(mRecyclerView).setOnItemClickListener(new ItemClickSupport.OnItemClickListener() {
@Override
public void onItemClicked(RecyclerView recyclerView, int position, View v) {
    // do it
}
});

关于recyclerview点击的简要说明,请看看这个littlerobots_blog

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) {}
}