RecyclerView Item Swipe to Dismiss 有时会卡住

Question

我正在使用 RecyclerView 滑动以在列表项后面显示一个操作按钮，而我的 RecyclerView 位于带有底部导航的片段中，一切进展顺利，但有时滑动停止并卡住，因此我无法完全滑动该项目。我需要你的帮助。我的代码：

主要活动中的代码：

ItemTouchHelper itemTouchhelper = new ItemTouchHelper(swipeController);
itemTouchhelper.attachToRecyclerView(movelistview);

movelistview.addItemDecoration(new RecyclerView.ItemDecoration() {
    @Override
    public void onDraw(Canvas c, RecyclerView parent, RecyclerView.State state) {
        swipeController.onDraw(c,"action");
    }
});

Swipe Controller 类中的代码：

public class SwipeController extends ItemTouchHelper.Callback {

    private static final float buttonWidth = 200;
    private boolean swipeBack = false;
    private ButtonsState buttonShowedState = ButtonsState.GONE;
    private RectF buttonInstance = null;
    private RecyclerView.ViewHolder currentItemViewHolder = null;
    private SwipeControllerActions buttonsActions = null;

    public SwipeController(SwipeControllerActions buttonsActions) {
        this.buttonsActions = buttonsActions;
    }

    @Override
    public int getMovementFlags(RecyclerView recyclerView, RecyclerView.ViewHolder viewHolder) {
        return makeMovementFlags(0, LEFT);
    }

    @Override
    public boolean onMove(RecyclerView recyclerView, RecyclerView.ViewHolder viewHolder, RecyclerView.ViewHolder target) {
        return false;
    }

    @Override
    public void onSwiped(RecyclerView.ViewHolder viewHolder, int direction) {

    }

    @Override
    public int convertToAbsoluteDirection(int flags, int layoutDirection) {
        if (swipeBack) {
            swipeBack = buttonShowedState != ButtonsState.GONE;
            return 0;
        }
        return super.convertToAbsoluteDirection(flags, layoutDirection);
    }

    @Override
    public void onChildDraw(Canvas c, RecyclerView recyclerView, RecyclerView.ViewHolder viewHolder, float dX, float dY, int actionState, boolean isCurrentlyActive) {
        if (actionState == ACTION_STATE_SWIPE) {
            if (buttonShowedState != ButtonsState.GONE) {
                // if (buttonShowedState == ButtonsState.LEFT_VISIBLE) dX = Math.max(dX, buttonWidth);
                if (buttonShowedState == ButtonsState.RIGHT_VISIBLE)
                    dX = Math.min(dX, -buttonWidth);
                super.onChildDraw(c, recyclerView, viewHolder, dX, dY, actionState, isCurrentlyActive);
            } else {
                setTouchListener(c, recyclerView, viewHolder, dX, dY, actionState, isCurrentlyActive);
            }
        }

        if (buttonShowedState == ButtonsState.GONE) {
            super.onChildDraw(c, recyclerView, viewHolder, dX, dY, actionState, isCurrentlyActive);
        }
        currentItemViewHolder = viewHolder;
    }

    private void setTouchListener(final Canvas c, final RecyclerView recyclerView, final RecyclerView.ViewHolder viewHolder, final float dX, final float dY, final int actionState, final boolean isCurrentlyActive) {
        recyclerView.setOnTouchListener(new View.OnTouchListener() {
            @Override
            public boolean onTouch(View v, MotionEvent event) {
                swipeBack = event.getAction() == MotionEvent.ACTION_CANCEL || event.getAction() == MotionEvent.ACTION_UP;
                if (swipeBack) {
                    if (dX < -buttonWidth) buttonShowedState = ButtonsState.RIGHT_VISIBLE;
                    //else if (dX > buttonWidth) buttonShowedState  = ButtonsState.LEFT_VISIBLE;

                    if (buttonShowedState != ButtonsState.GONE) {
                        setTouchDownListener(c, recyclerView, viewHolder, dX, dY, actionState, isCurrentlyActive);
                        setItemsClickable(recyclerView, false);
                    }
                }
                return false;
            }
        });
    }

    private void setTouchDownListener(final Canvas c, final RecyclerView recyclerView, final RecyclerView.ViewHolder viewHolder, final float dX, final float dY, final int actionState, final boolean isCurrentlyActive) {
        recyclerView.setOnTouchListener(new View.OnTouchListener() {
            @Override
            public boolean onTouch(View v, MotionEvent event) {
                if (event.getAction() == MotionEvent.ACTION_DOWN) {
                    setTouchUpListener(c, recyclerView, viewHolder, dX, dY, actionState, isCurrentlyActive);
                }
                return false;
            }
        });
    }

    private void setTouchUpListener(final Canvas c, final RecyclerView recyclerView, final RecyclerView.ViewHolder viewHolder, final float dX, final float dY, final int actionState, final boolean isCurrentlyActive) {
        recyclerView.setOnTouchListener(new View.OnTouchListener() {
            @Override
            public boolean onTouch(View v, MotionEvent event) {
                if (event.getAction() == MotionEvent.ACTION_UP) {
                    SwipeController.super.onChildDraw(c, recyclerView, viewHolder, 0F, dY, actionState, isCurrentlyActive);
                    recyclerView.setOnTouchListener(new View.OnTouchListener() {
                        @Override
                        public boolean onTouch(View v, MotionEvent event) {
                            return false;
                        }
                    });
                    setItemsClickable(recyclerView, true);
                    swipeBack = false;

                    if (buttonsActions != null && buttonInstance != null && buttonInstance.contains(event.getX(), event.getY())) {
                    /*if (buttonShowedState == ButtonsState.LEFT_VISIBLE) {
                        buttonsActions.onLeftClicked(viewHolder.getAdapterPosition());
                    }else*/
                        if (buttonShowedState == ButtonsState.RIGHT_VISIBLE) {
                            buttonsActions.onRightClicked(viewHolder.getAdapterPosition());
                        }
                    }
                    buttonShowedState = ButtonsState.GONE;
                    currentItemViewHolder = null;
                }
                return false;
            }
        });
    }

    private void setItemsClickable(RecyclerView recyclerView, boolean isClickable) {
        for (int i = 0; i < recyclerView.getChildCount(); ++i) {
            recyclerView.getChildAt(i).setClickable(isClickable);
        }
    }

    private void drawButtons(Canvas c, RecyclerView.ViewHolder viewHolder, String text) {
        float buttonWidthWithoutPadding = buttonWidth - 0;
        float corners = 0;

        View itemView = viewHolder.itemView;
        Paint p = new Paint();
        int position = viewHolder.getAdapterPosition();
        String button_text = "Report";

        if (position >= 0) {
            if (MainApplication.moves_list.get(position).getMove_userId().equals(MainApplication.user_id)) {
                button_text = "Delete";
            } else {
                button_text = "Report";
            }
        }

        RectF rightButton = new RectF(itemView.getRight() - buttonWidthWithoutPadding, itemView.getTop() + 0, itemView.getRight(), itemView.getBottom() - 0);
        p.setColor(Color.RED);
        c.drawRoundRect(rightButton, corners, corners, p);
        drawText(button_text, c, rightButton, p);

        buttonInstance = null;
        if (buttonShowedState == ButtonsState.RIGHT_VISIBLE) {
            buttonInstance = rightButton;
        }
    }

    private void drawText(String text, Canvas c, RectF button, Paint p) {
        float textSize = 40;
        p.setColor(Color.WHITE);
        p.setAntiAlias(true);
        p.setTextSize(textSize);

        float textWidth = p.measureText(text);
        c.drawText(text, button.centerX() - (textWidth / 2), button.centerY() + (textSize / 2), p);
    }

    public void onDraw(Canvas c, String text) {
        if (currentItemViewHolder != null) {
            drawButtons(c, currentItemViewHolder, text);
        }
    }

}

Answer 1

我也遇到了同样的问题。滑动按钮卡在 UI 中，在 recyclerview 后面。所以这是我找到的最简单、最好的解决方案。

在 SwipeViewController 中创建新函数，如下所示

public void setSwipeBack()
{
    swipeBack = false;
    buttonShowedState = ButtonsStates.GONE;

}

并在您的片段中使用此功能，您将在同一回收器视图中填充数据。 如下

setSwipeBack();

Answer 2

我也遇到了同样的问题，但是解决起来很简单。

这将在父容器拦截您的触摸事件时发生。任何覆盖 ViewGroup.onInterceptTouchEvent(MotionEvent) 的 ViewGroup 都可以做到这一点（例如 RecyclerView 或 ScrollView）。

这将导致当 Y 值发生轻微变化时从你的 motionEvent 返回 ACTION_CANCEL，并将触摸事件发送到父视图。

处理此问题的正确方法是在您认为需要保留运动事件时在父视图上调用 ViewParent.requestDisallowInterceptTouchEvent(boolean) 方法。

这是一个简单的例子（attemptClaimDrag() 方法取自 android 源代码）：

/**
 * Tries to claim the user's drag motion, and requests disallowing any
 * ancestors from stealing events in the drag.
 */
private void attemptClaimDrag() {
    // parent = yourView.getParent();
    if (parent != null) {
        parent.requestDisallowInterceptTouchEvent(true);
    }
}

在你的 onTouchEvent() 或 onTouch() 中：

@Override
public boolean onTouchEvent(MotionEvent event) {
    if (event.getAction() == MotionEvent.ACTION_DOWN) {
        if (iWantToKeepThisEventForMyself(event)) {
            attemptClaimDrag();
        }
        //your logic here
    } else {
        //your logic here
    }
}