Question

我的应用程序包含一副纸牌。卡座中的大多数卡都是用draggableView制作的。我试图制作它，以便在屏幕上双击可以使卡上的按钮消失/重新出现。看完post之后，我试着试一试。我在我的draggableView类中将UITapGesture放入我的initWithFrame方法中，如下所示：

- (id)initWithFrame:(CGRect)frame
self = [super initWithFrame:frame];
if (self) {
    [self addSubviewFromNib];
    [self setupView];
    panGestureRecognizer = [[UIPanGestureRecognizer alloc]initWithTarget:self action:@selector(beingDragged:)];
    cardWidth = frame.size.width;
    cardHeight = frame.size.height;
    type = 0;
    panGestureRecognizer.delegate = self;
    panGestureRecognizer.cancelsTouchesInView = NO;
    _backgroundScrollView.panGestureRecognizer.cancelsTouchesInView = NO;
    //...more code above....
    _backgroundScrollView.userInteractionEnabled = YES;
    tapGestureRecognizer = [[UITapGestureRecognizer alloc]   initWithTarget:_backgroundScrollView action:@selector(doubleTap)];
    tapGestureRecognizer.delegate = _backgroundScrollView;
    tapGestureRecognizer.numberOfTapsRequired = 2;
[_backgroundScrollView addGestureRecognizer:tapGestureRecognizer];
[self addGestureRecognizer:panGestureRecognizer];

}

 - (void) doubleTap: (UITapGestureRecognizer *)tapGesturerecognizer{

    _mapButton.hidden = !_mapButton.hidden;
    _menuButton.hidden = !_menuButton.hidden;
    _phoneButton.hidden = !_phoneButton.hidden;
    reviewButton.hidden = !reviewButton.hidden;
    _shareButton.hidden = !_shareButton.hidden;

}


- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldBeRequiredToFailByGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer {

    // If the gesture recognizer is a UITapGestureRecongizer, but the other
    // gesture detected is a UIPanGestureRecognizer, require the
    // UITapGestureRecognizer to fail.
    if ([gestureRecognizer isKindOfClass:[UITapGestureRecognizer class]] &&
        [otherGestureRecognizer isKindOfClass:[UIPanGestureRecognizer class]]) {
        return YES;
    } else {
        return NO;
    }
}



- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer
{
    if ([gestureRecognizer isKindOfClass:[UITapGestureRecognizer class]]) {
        return YES;
    }
    if ([gestureRecognizer isKindOfClass:[UIPanGestureRecognizer class]]) {
        UIPanGestureRecognizer *panGesture = (UIPanGestureRecognizer *)gestureRecognizer;
        CGPoint velocity = [panGesture velocityInView:self];
        return fabs(velocity.y) <= fabs(velocity.x);
    }
    return YES;
}

然而，如果我双击，我会得到这个sib abrt错误：

 -[UITapGestureRecognizer velocityInView:]: unrecognized selector sent to instance 0x7f9f9a244230
 *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[UITapGestureRecognizer velocityInView:]: unrecognized selector sent to instance 0x7f9f9a244230'

我假设这意味着PanGestureRecognizer和TapGesture Recognizer之间存在错误。我该如何解决？

编辑：仍未解决，但如果我将tapGesture更改为可拖动视图（因此，自我），而不是_backgroundScrollView，我会收到此错误：

Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[DraggableView doubleTap]: unrecognized selector sent to instance 0x7fefdd9e4f70'

其他编辑：我将其更改回backgroundScrollView，现在我将其视为错误：

[UIScrollView doubleTap]: unrecognized selector sent to instance 0x7fe5130af000

Answer 1

gestureRecognizerShouldBegin将被调用，当手势识别器即将触发触摸时，它可以是轻击手势，也可以是平移手势。你需要检查一下gestureRecogniser类型，然后再继续。

实施以下方法（取自here）以允许同时识别手势：

 - (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldBeRequiredToFailByGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer {

    // If the gesture recognizer is a UITapGestureRecongizer, but the other
    // gesture detected is a UIPanGestureRecognizer, require the
    // UIPanGestureRecognizer to fail.
    if ([gestureRecognizer isKindOfClass:[UITapGestureRecognizer class]] &&
        [otherGestureRecognizer isKindOfClass:[UIPanGestureRecognizer class]])  {
       return YES;
    } else {
       return NO;
    }
}

并且在另一个委托方法中，崩溃原因告诉您：

-[UITapGestureRecognizer velocityInView:]: unrecognized selector sent to instance 0x7f9f9a2

velocityInView被调用错误的手势类型，为了避免这些错误，修改你的委托方法如下：

- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer 
{
  if ([gestureRecognizer isKindOfClass:[UITapGestureRecognizer class]]) {     
       return YES;
  }
  if ([gestureRecognizer isKindOfClass:[UIPanGestureRecognizer class]]) { 
       UIPanGestureRecogniser *panGesture = (UIPanGestureRecongiser *)gestureRecogniser;    
       CGPoint velocity = [panGesture velocityInView:self];
       return fabs(velocity.y) <= fabs(velocity.x);
  }
   return YES;
}

Answer 2

我的错误：在我的h文件中，我需要使用draggableView作为tapGesture的委托，然后将gestureRecognizer插入到UIGestureRecognizerDelegate协议中，如下所示：

@protocol UIGestureRecognizerDelegate <NSObject>
- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer;
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldBeRequiredToFailByGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer;
@end

冲突与PanGesture和TapGesture

2 个答案: