70

我正在试验支持库的 recyclerview 和卡片。我有卡片的recyclerview。每张卡片的右上角都有一个“x”图标以将其删除：

卡 xml list_item.xml，：

<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.CardView
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_margin="5dp">
<RelativeLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    <TextView
        android:id="@+id/taskDesc"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:textSize="40sp"
        android:text="hi"/>
    <ImageView
        android:id="@+id/xImg"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:layout_alignParentRight="true"
        android:src="@drawable/ic_remove"/>
</RelativeLayout>
</android.support.v7.widget.CardView>

我试图用我将在notifyItemRemoved(position)中使用的位置标记该行TaskAdapter.java：

public class TaskAdapter extends RecyclerView.Adapter<TaskAdapter.TaskViewHolder>  {

private List<Task> taskList;
private TaskAdapter thisAdapter = this;


// cache of views to reduce number of findViewById calls
public static class TaskViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
    protected TextView taskTV;
    protected ImageView closeBtn;
    public TaskViewHolder(View v) {
        super(v);
        taskTV = (TextView)v.findViewById(R.id.taskDesc);
    }

    @Override
    public void onClick(View v) {
        int position = v.getTag();
        adapter.notifyItemRemoved(position);
    }
}


public TaskAdapter(List<Task> tasks) {
    if(tasks == null)
        throw new IllegalArgumentException("tasks cannot be null");
    taskList = tasks;
}


// onBindViewHolder binds a model to a viewholder
@Override
public void onBindViewHolder(TaskViewHolder taskViewHolder, int pos) {
    final int position = pos;
    Task currTask = taskList.get(pos);
    taskViewHolder.taskTV.setText(currTask.getDescription());

    taskViewHolder.closeBtn.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            thisAdapter.notifyItemRemoved(position);
        }
    });
}

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


// inflates row to create a viewHolder
@Override
public TaskViewHolder onCreateViewHolder(ViewGroup parent, int pos) {
    View itemView = LayoutInflater.from(parent.getContext()).
                                   inflate(R.layout.list_item, parent, false);

    return new TaskViewHolder(itemView);
}
}

这不起作用，因为您不能设置标签，也不能从onClick.

4

13 回答 13

126

设置您onClickListener的 s onBindViewHolder()，您可以从那里访问该位置。如果您将它们设置在您的ViewHolder位置，您将不知道点击了哪个位置，除非您也将位置传递给ViewHolder

编辑

正如所pskink指出ViewHolder的getPosition()那样，您最初的做法是正确的。

单击视图时，您可以getPosition()在您的视图中使用ViewHolder它并返回位置

更新

getPosition()现在已弃用并替换为getAdapterPosition()

2020 年更新

getAdapterPosition()现在已弃用并替换为getAbsoluteAdapterPosition()orgetBindingAdapterPosition()

科特林代码：

override fun onBindViewHolder(holder: MyHolder, position: Int) {
        // - get element from your dataset at this position
        val item = myDataset.get(holder.absoluteAdapterPosition)
    }
于 2014-10-31T19:43:29.770 回答
17

另一种方法 - 使用View 类的setTag()和getTag()方法。

  1. 在适配器的 onBindViewHolder 方法中使用setTag()

    @Override
public void onBindViewHolder(myViewHolder viewHolder, int position) {
    viewHolder.mCardView.setTag(position);
}

    其中 mCardView 在 myViewHolder 类中定义

    private class myViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
           public View mCardView;

           public myViewHolder(View view) {
               super(view);
               mCardView = (CardView) view.findViewById(R.id.card_view);

               mCardView.setOnClickListener(this);
           }
       }

  2. 在您的 OnClickListener 实现中使用getTag()

    @Override
public void onClick(View view) {
    int position = (int) view.getTag();           

//display toast with position of cardview in recyclerview list upon click
Toast.makeText(view.getContext(),Integer.toString(position),Toast.LENGTH_SHORT).show();
}

有关更多详细信息，请参阅https://stackoverflow.com/a/33027953/4658957

于 2015-10-09T00:43:49.130 回答
8

为了补充@tyczj的答案：

通用适配器伪代码：

public abstract class GenericRecycleAdapter<T, K extends RecyclerView.ViewHolder> extends RecyclerView.Adapter{ 

private List<T> mList;
//default implementation code 

public abstract int getLayout();

@Override
    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View v = LayoutInflater.from(parent.getContext())
                .inflate(getLayout(), parent, false);
        return getCustomHolder(v);
    }

    public Holders.TextImageHolder getCustomHolder(View v) {
        return new Holders.TextImageHolder(v){
            @Override
            public void onClick(View v) {
                onItem(mList.get(this.getAdapterPosition()));
            }
        };
    }

abstract void onItem(T t);

 @Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
    onSet(mList.get(position), (K) holder);

}

public abstract void onSet(T item, K holder);

}

视图持有者：

public class Holders  {

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

        public TextView text;

        public TextImageHolder(View itemView) {
            super(itemView);
            text = (TextView) itemView.findViewById(R.id.text);
            text.setOnClickListener(this);


        }

        @Override
        public void onClick(View v) {

        }
    }


}

适配器使用：

public class CategoriesAdapter extends GenericRecycleAdapter<Category, Holders.TextImageHolder> {


    public CategoriesAdapter(List<Category> list, Context context) {
        super(list, context);
    }

    @Override
    void onItem(Category category) {

    }


    @Override
    public int getLayout() {
        return R.layout.categories_row;
    }

    @Override
    public void onSet(Category item, Holders.TextImageHolder holder) {

    }



}
于 2015-07-08T08:22:55.727 回答
4 
 public static class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {

    FrameLayout root;


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

        root = (FrameLayout) itemView.findViewById(R.id.root);
        root.setOnClickListener(this);
    }


    @Override
    public void onClick(View v) {
        LogUtils.errorLog("POS_CLICKED: ",""+getAdapterPosition());
    }
}
于 2016-01-29T11:17:42.663 回答
3

就个人而言，我发现并且对我有用的最简单方法如下：

在“RecycleAdapter”类（子类）中创建一个接口

public interface ClickCallback {
    void onItemClick(int position);
}

在构造函数中添加一个接口的变量作为参数。

private String[] items;
private ClickCallback callback;

public RecyclerAdapter(String[] items, ClickCallback clickCallback) {
    this.items = items;
    this.callback = clickCallback;
}

在 ViewHolder（另一个子类）中设置一个 Click 侦听器，并通过接口将“位置”传递给

    AwesomeViewHolder(View itemView) {
        super(itemView);
        itemView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                callback.onItemClick(getAdapterPosition());
            }
        });
        mTextView = (TextView) itemView.findViewById(R.id.mTextView);
    }

现在，在活动/片段中初始化回收器适配器时，只需创建一个新的“ClickCallback”（接口）

String[] values = {"Hello","World"};
RecyclerAdapter recyclerAdapter = new RecyclerAdapter(values, new RecyclerAdapter.ClickCallback() {
    @Override
    public void onItemClick(int position) {
         // Do anything with the item position
    }
});

对我来说就是这样。:)

于 2017-03-20T13:58:38.130 回答
2

获得专注的孩子，并用它来获得适配器中的位置。

mRecyclerView.getChildAdapterPosition(mRecyclerView.getFocusedChild())
于 2016-08-11T23:47:07.520 回答
2

1.创建类名RecyclerTouchListener.java

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

public class RecyclerTouchListener implements RecyclerView.OnItemTouchListener 
{

private GestureDetector gestureDetector;
private ClickListener clickListener;

public RecyclerTouchListener(Context context, final RecyclerView recyclerView, final ClickListener clickListener) {
    this.clickListener = clickListener;
    gestureDetector = 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 && clickListener != null) {
                clickListener.onLongClick(child, recyclerView.getChildAdapterPosition(child));
            }
        }
    });
}

@Override
public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent e) {

    View child = rv.findChildViewUnder(e.getX(), e.getY());
    if (child != null && clickListener != null && gestureDetector.onTouchEvent(e)) {
        clickListener.onClick(child, rv.getChildAdapterPosition(child));
    }
    return false;
}

@Override
public void onTouchEvent(RecyclerView rv, MotionEvent e) {
}

@Override
public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) {

}

public interface ClickListener {
    void onClick(View view, int position);

    void onLongClick(View view, int position);
}
}

2.调用RecyclerTouchListener

recycleView.addOnItemTouchListener(new RecyclerTouchListener(this, recycleView, 
new RecyclerTouchListener.ClickListener() {
    @Override
    public void onClick(View view, int position) {
        Toast.makeText(MainActivity.this,Integer.toString(position),Toast.LENGTH_SHORT).show();
    }

    @Override
    public void onLongClick(View view, int position) {

    }
}));
于 2018-09-01T08:35:00.397 回答
2

我这样解决了

class MyOnClickListener implements View.OnClickListener {
        @Override
        public void onClick(View v) {

            int itemPosition = mRecyclerView.getChildAdapterPosition(v);

            myResult = results.get(itemPosition);


        }
    }

在适配器中

@Override
        public MyAdapter.ViewHolder onCreateViewHolder(ViewGroup parent,
                                                       int viewType) {            
            View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.list_wifi, parent, false);
            v.setOnClickListener(new MyOnClickListener());
            ViewHolder vh = new ViewHolder(v);
            return vh;
        }
于 2016-07-19T12:42:14.073 回答
1

我认为获得项目位置的最正确方法是

View.OnClickListener onClickListener = new View.OnClickListener() {
    @Override public void onClick(View v) {
      View view = v;
      View parent = (View) v.getParent();
      while (!(parent instanceof RecyclerView)){
        view=parent;
        parent = (View) parent.getParent();
      }
      int position = recyclerView.getChildAdapterPosition(view);
}

因为视图，您单击的并不总是行布局的根视图。如果视图不是根视图（例如按钮），您将获得 Class cast 异常。因此，首先我们需要找到视图，它是您的 reciclerview 的直接孩子。然后，使用 recyclerView.getChildAdapterPosition(view); 找到位置

于 2016-11-07T13:01:57.110 回答
1

onBindViewHolder() 会为每个项目调用，并且在 onBindVieHolder() 内设置点击侦听器是不必要的重复选项，因为您可以在 ViewHolder 构造函数中调用它一次。

public class MyViewHolder extends RecyclerView.ViewHolder 
      implements View.OnClickListener{
   public final TextView textView; 

   public MyViewHolder(View view){
      textView = (TextView) view.findViewById(R.id.text_view);
      view.setOnClickListener(this);
      // getAdapterPosition() retrieves the position here.
   } 

   @Override
   public void onClick(View v){
      // Clicked on item 
      Toast.makeText(mContext, "Clicked on position: " + getAdapterPosition(), Toast.LENGTH_SHORT).show();
   }
}
于 2018-10-01T14:05:13.817 回答
0 
@Override
public void onClick(View v) {
     int pos = getAdapterPosition();
}

就这么简单，上ViewHolder

于 2019-08-30T20:26:20.217 回答
0

无需让您的 ViewHolder 实现 View.OnClickListener。您可以通过在 RecyclerView.Adapter 的 onCreateViewHolder 方法中设置点击监听器来直接获取点击位置，下面是代码示例：

public class ItemListAdapterRecycler extends RecyclerView.Adapter<ItemViewHolder>
{

    private final List<Item> items;

    public ItemListAdapterRecycler(List<Item> items)
    {
        this.items = items;
    }

    @Override
    public ItemViewHolder onCreateViewHolder(final ViewGroup parent, int viewType)
    {
        View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_row, parent, false);

        view.setOnClickListener(new View.OnClickListener()
        {
            @Override
            public void onClick(View view)
            {
                int currentPosition = getClickedPosition(view);
                Log.d("DEBUG", "" + currentPosition);
            }
        });

        return new ItemViewHolder(view);
    }

    @Override
    public void onBindViewHolder(ItemViewHolder itemViewHolder, int position)
    {
        ...
    }

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

    private int getClickedPosition(View clickedView)
    {
        RecyclerView recyclerView = (RecyclerView) clickedView.getParent();
        ItemViewHolder currentViewHolder = (ItemViewHolder) recyclerView.getChildViewHolder(clickedView);
        return currentViewHolder.getAdapterPosition();
    }

}
于 2018-03-28T10:09:26.403 回答
0

使用数据绑定时，您需要从项目的单击侦听器内部了解 RecyclerView 单击位置：

科特林

    val recyclerView = view.parent as RecyclerView
    val position = recyclerView.getChildAdapterPosition(view)
于 2020-06-24T06:03:31.893 回答