处理按钮在RecyclerView中的行内单击

Question

我正在使用以下代码来处理行点击.(来源)

static 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.getChildPosition(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.getChildPosition(child));
        }
        return false;
    }

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

但是,如果我想在每一行上说一个删除按钮,这是有效的.我不确定如何实现这一点.

我附加了OnClick监听器来删除工作的按钮(删除行),但它也会触发整行上的onclick.

如果单击一个按钮,任何人都可以帮助我避免完全行单击.

谢谢.

Answer 1

这就是我在recyclelerView中处理多个onClick事件的方法:

编辑:已更新以包含回调(如其他注释中所述).我已经使用了一个WeakReference在ViewHolder消除潜在的内存泄漏.

定义界面:

public interface ClickListener {

    void onPositionClicked(int position);

    void onLongClicked(int position);
}

那么适配器:

public class MyAdapter extends RecyclerView.Adapter<MyAdapter.MyViewHolder> {

    private final ClickListener listener;
    private final List<MyItems> itemsList;

    public MyAdapter(List<MyItems> itemsList, ClickListener listener) {
        this.listener = listener;
        this.itemsList = itemsList;
    }

    @Override public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        return new MyViewHolder(LayoutInflater.from(parent.getContext()).inflate(R.layout.my_row_layout), parent, false), listener);
    }

    @Override public void onBindViewHolder(MyViewHolder holder, int position) {
        // bind layout and data etc..
    }

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

    public static class MyViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener, View.OnLongClickListener {

        private ImageView iconImageView;
        private TextView iconTextView;
        private WeakReference<ClickListener> listenerRef;

        public MyViewHolder(final View itemView, ClickListener listener) {
            super(itemView);

            listenerRef = new WeakReference<>(listener);
            iconImageView = (ImageView) itemView.findViewById(R.id.myRecyclerImageView);
            iconTextView = (TextView) itemView.findViewById(R.id.myRecyclerTextView);

            itemView.setOnClickListener(this);
            iconTextView.setOnClickListener(this);
            iconImageView.setOnLongClickListener(this);
        }

        // onClick Listener for view
        @Override
        public void onClick(View v) {

            if (v.getId() == iconTextView.getId()) {
                Toast.makeText(v.getContext(), "ITEM PRESSED = " + String.valueOf(getAdapterPosition()), Toast.LENGTH_SHORT).show();
            } else {
                Toast.makeText(v.getContext(), "ROW PRESSED = " + String.valueOf(getAdapterPosition()), Toast.LENGTH_SHORT).show();
            }

            listenerRef.get().onPositionClicked(getAdapterPosition());
        }


        //onLongClickListener for view
        @Override
        public boolean onLongClick(View v) {

            final AlertDialog.Builder builder = new AlertDialog.Builder(v.getContext());
            builder.setTitle("Hello Dialog")
                    .setMessage("LONG CLICK DIALOG WINDOW FOR ICON " + String.valueOf(getAdapterPosition()))
                    .setPositiveButton("OK", new DialogInterface.OnClickListener() {
                        @Override
                        public void onClick(DialogInterface dialog, int which) {

                        }
                    });

            builder.create().show();
            listenerRef.get().onLongClicked(getAdapterPosition());
            return true;
        }
    }
}

然后在你的活动/片段中 - 你可以实现的任何东西:Clicklistener- 或者如果你愿意的话,也可以使用匿名类:

MyAdapter adapter = new MyAdapter(myItems, new ClickListener() {
            @Override public void onPositionClicked(int position) {
                // callback performed on click
            }

            @Override public void onLongClicked(int position) {
                // callback performed on click
            }
        });

要获取单击的项目,您将匹配视图ID ievgetId()== whateverItem.getId()

希望这种方法有帮助!

Answer 2

我发现通常:

• 我需要使用多个监听器,因为我有几个按钮.
• 我希望我的逻辑在活动中,而不是适配器或视图.

所以@mark-keen的答案效果很好但是有一个界面提供了更多的灵活性:

public static class MyViewHolder extends RecyclerView.ViewHolder {

    public ImageView iconImageView;
    public TextView iconTextView;

    public MyViewHolder(final View itemView) {
        super(itemView);

        iconImageView = (ImageView) itemView.findViewById(R.id.myRecyclerImageView);
        iconTextView = (TextView) itemView.findViewById(R.id.myRecyclerTextView);

        iconTextView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                onClickListener.iconTextViewOnClick(v, getAdapterPosition());
            }
        });
        iconImageView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                onClickListener.iconImageViewOnClick(v, getAdapterPosition());
            }
        });
    }
}

在适配器中定义onClickListener的位置:

public MyAdapterListener onClickListener;

public interface MyAdapterListener {

    void iconTextViewOnClick(View v, int position);
    void iconImageViewOnClick(View v, int position);
}

并且可能通过构造函数设置:

public MyAdapter(ArrayList<MyListItems> newRows, MyAdapterListener listener) {

    rows = newRows;
    onClickListener = listener;
}

然后,您可以处理Activity中的事件或使用RecyclerView的任何位置:

mAdapter = new MyAdapter(mRows, new MyAdapter.MyAdapterListener() {
                    @Override
                    public void iconTextViewOnClick(View v, int position) {
                        Log.d(TAG, "iconTextViewOnClick at position "+position);
                    }

                    @Override
                    public void iconImageViewOnClick(View v, int position) {
                        Log.d(TAG, "iconImageViewOnClick at position "+position);
                    }
                });
mRecycler.setAdapter(mAdapter);

Answer 3

我想要一个没有创建任何额外对象(即监听器)的解决方案,这些对象必须在以后进行垃圾收集,并且不需要在适配器类中嵌套视图持有者.

在ViewHolder课堂上

private static class MyViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {

        private final TextView ....// declare the fields in your view
        private ClickHandler ClickHandler;

        public MyHolder(final View itemView) {
            super(itemView);
            nameField = (TextView) itemView.findViewById(R.id.name);
            //find other fields here...
            Button myButton = (Button) itemView.findViewById(R.id.my_button);
            myButton.setOnClickListener(this);
        }
        ...
        @Override
        public void onClick(final View view) {
            if (clickHandler != null) {
                clickHandler.onMyButtonClicked(getAdapterPosition());
            }
        }

注意事项:ClickHandler接口已定义,但未在此处初始化,因此onClick方法中没有假设它已初始化.

该ClickHandler界面看起来是这样的:

private interface ClickHandler {
    void onMyButtonClicked(final int position);
} 

在适配器中,在构造函数中设置一个'ClickHandler'实例,并覆盖onBindViewHolder,以在视图持有者上初始化`clickHandler':

private class MyAdapter extends ...{

    private final ClickHandler clickHandler;

    public MyAdapter(final ClickHandler clickHandler) {
        super(...);
        this.clickHandler = clickHandler;
    }

    @Override
    public void onBindViewHolder(final MyViewHolder viewHolder, final int position) {
        super.onBindViewHolder(viewHolder, position);
        viewHolder.clickHandler = this.clickHandler;
    }

注意:我知道viewHolder.clickHandler可能会使用完全相同的值多次设置,但这比检查null和分支更便宜,而且没有内存开销,只需要额外的指令.

最后,在创建适配器时,您必须将ClickHandler实例传递给构造函数,如下所示:

adapter = new MyAdapter(new ClickHandler() {
    @Override
    public void onMyButtonClicked(final int position) {
        final MyModel model = adapter.getItem(position);
        //do something with the model where the button was clicked
    }
});

注意,这adapter是一个成员变量,而不是局部变量

Answer 4

如果您已经有一个回收器触摸监听器并且想要处理其中的所有触摸事件，而不是在视图持有者中单独处理按钮触摸事件，那么只是想添加另一个解决方案。这个类的改编版本所做的关键是在点击时在 onItemClick() 回调中返回按钮视图，而不是项目容器。然后，您可以测试视图是否为按钮，并执行不同的操作。请注意，长按按钮被解释为仍然长按整行。

public class RecyclerItemClickListener implements RecyclerView.OnItemTouchListener
{
    public static interface OnItemClickListener
    {
        public void onItemClick(View view, int position);
        public void onItemLongClick(View view, int position);
    }

    private OnItemClickListener mListener;
    private 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)
            {
                // Important: x and y are translated coordinates here
                final ViewGroup childViewGroup = (ViewGroup) recyclerView.findChildViewUnder(e.getX(), e.getY());

                if (childViewGroup != null && mListener != null) {
                    final List<View> viewHierarchy = new ArrayList<View>();
                    // Important: x and y are raw screen coordinates here
                    getViewHierarchyUnderChild(childViewGroup, e.getRawX(), e.getRawY(), viewHierarchy);

                    View touchedView = childViewGroup;
                    if (viewHierarchy.size() > 0) {
                        touchedView = viewHierarchy.get(0);
                    }
                    mListener.onItemClick(touchedView, recyclerView.getChildPosition(childViewGroup));
                    return true;
                }

                return false;
            }

            @Override
            public void onLongPress(MotionEvent e)
            {
                View childView = recyclerView.findChildViewUnder(e.getX(), e.getY());

                if(childView != null && mListener != null)
                {
                    mListener.onItemLongClick(childView, recyclerView.getChildPosition(childView));
                }
            }
        });
    }

    public void getViewHierarchyUnderChild(ViewGroup root, float x, float y, List<View> viewHierarchy) {
        int[] location = new int[2];
        final int childCount = root.getChildCount();

        for (int i = 0; i < childCount; ++i) {
            final View child = root.getChildAt(i);
            child.getLocationOnScreen(location);
            final int childLeft = location[0], childRight = childLeft + child.getWidth();
            final int childTop = location[1], childBottom = childTop + child.getHeight();

            if (child.isShown() && x >= childLeft && x <= childRight && y >= childTop && y <= childBottom) {
                viewHierarchy.add(0, child);
            }
            if (child instanceof ViewGroup) {
                getViewHierarchyUnderChild((ViewGroup) child, x, y, viewHierarchy);
            }
        }
    }

    @Override
    public boolean onInterceptTouchEvent(RecyclerView view, MotionEvent e)
    {
        mGestureDetector.onTouchEvent(e);

        return false;
    }

    @Override
    public void onTouchEvent(RecyclerView view, MotionEvent motionEvent){}

    @Override
    public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) {

    }
}

然后从活动/片段中使用它：

recyclerView.addOnItemTouchListener(createItemClickListener(recyclerView));

    public RecyclerItemClickListener createItemClickListener(final RecyclerView recyclerView) {
        return new RecyclerItemClickListener (context, recyclerView, new RecyclerItemClickListener.OnItemClickListener() {
            @Override
            public void onItemClick(View view, int position) {
                if (view instanceof AppCompatButton) {
                    // ... tapped on the button, so go do something
                } else {
                    // ... tapped on the item container (row), so do something different
                }
            }

            @Override
            public void onItemLongClick(View view, int position) {
            }
        });
    }