iOS 模拟器在随机时间后停止正确识别手势

Question

对不起，这要多久了。这对我来说是个谜，正在寻找任何人可能有的任何指针。

iOS 模拟器中 UIGestureRecognizer 的工作方式和传递接触点的方式似乎存在错误，该错误会一直持续到模拟器重新启动。即使杀死应用程序并在模拟器中重新启动它也不能修复它。修复它（暂时）的唯一方法是完全退出模拟器并重新启动它。

我在 UIViewController 子类中有一个 SKView 子类。 SKView 子类占据 UIViewController 的底部，顶部包含一些按钮和其他控件。游戏涉及水龙头和平底锅，由拥有 SKScene 子类的 SKView 子类拥有的 UIGestureControllers 管理。

在任意时间段后，手势停止正常工作。在 SKScene 拥有的视图中，它们都没有被正确识别。如果我在 SKView 外部和父 UIViewController 中单击，它们会显示出来，但坐标都是错误的。它也会出现状态错误 - 有时 UIPanGestureRecognizer 认为有两个手指按下而不是只有一个。 UIPanGestureRecognizer 同样关闭。这种行为没有可识别的模式 - 它只是突然开始。

这里是初始化SKView及其场景的相关代码：

    SKView * _gameView = [[SKView alloc] initWithFrame : gameRect];
    _gameView.clipsToBounds = YES;
    // _gameView.scene is an SKScene subclass
    CGSize gameSize = CGSizeMake(_gameView.bounds.size.width,
                                 _gameView.bounds.size.width);
    _scene = [[GameScene alloc] initWithSize : gameSize];
    // Present the scene.
    [_gameView presentScene : _scene];
    [self.view addSubview : _gameView];

这是注册 UIGestureControllers 的 SKScene 子类中的代码：

- (void) initializeGestureRecognition : (SKView *) view
{
    UIPanGestureRecognizer * panRecognizer = [[UIPanGestureRecognizer alloc] initWithTarget : self action : @selector (handlePanGesture:)];
    UITapGestureRecognizer * tapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget : self action : @selector (handleTapGesture:)];
    panRecognizer.delegate = self;
    tapRecognizer.delegate = self;
    panRecognizer.maximumNumberOfTouches = 2;
    [tapRecognizer requireGestureRecognizerToFail : panRecognizer];
    [view addGestureRecognizer : panRecognizer];
    [view addGestureRecognizer : tapRecognizer];
}

这是 UIPanGestureRecognizer 的 handlePanGesture 委托的代码：

-(void) handlePanGesture : (UIPanGestureRecognizer*) panRecognizer
{
    self.deltaInView = [panRecognizer translationInView : self.view];
    self.deltaInScene = CGPointMake(deltaInView.x, -(deltaInView.y));
    if (UIGestureRecognizerStateChanged == panRecognizer.state)
        {
            self.panTouchPoint = [self getPanTouchPoint : panRecognizer];
        }
    else if (UIGestureRecognizerStateEnded == panRecognizer.state)
        {
            // Other non-relevant stuff here
        }
}

- (CGPoint) didGetPanTouchPoint : (UIPanGestureRecognizer*) panRecognizer
{
    CGPoint touchPoint = CGPointMake(0.0, 0.0);
    if (2 == panRecognizer.numberOfTouches)
    {
        CGPoint tempPoint = [self calculateSafeCentroidPointFromRecognizer : panRecognizer];
        touchPoint = [self convertPointFromView : tempPoint];
    }
    else if (1 == panRecognizer.numberOfTouches)
    {
        CGPoint tempPoint = [panRecognizer locationOfTouch : 0
                                                    inView : self.view];
        touchPoint = [self convertPointFromView : tempPoint];
    }
    return touchPoint;
}


- (CGPoint) calculateSafeCentroidPointFromRecognizer : (UIGestureRecognizer*) recognizer
{
    CGPoint thisPointInView = [recognizer locationOfTouch : 0
                                                   inView : self.view];
    CGPoint thatPointInView = [recognizer locationOfTouch : 1
                                                   inView : self.view];
    CGPoint safePoint = [self calculateCentroidPoint : thisPointInView
                                         secondPoint : thatPointInView];
    return safePoint;
}


CGPoint CalculateCentroidPoint(const CGPoint * thisPoint,
                               const CGPoint * thatPoint)
{
    CGPoint centroidPoint = CGPointMake((thisPoint->x + thatPoint->x) / 2.0),
                                        (thisPoint->y + thatPoint->y) / 2.0));
    return centroidPoint;
}

这是 UITapGestureRecognizer 的 handleTapGesture 委托的代码：

- (void) handleTapGesture : (UIGestureRecognizer *) gestureRecognizer
{
    if (gestureRecognizer.state == UIGestureRecognizerStateEnded)
    {
        UITapGestureRecognizer * tapRecognizer = (UITapGestureRecognizer*) gestureRecognizer;
        CGPoint viewTouchLocation = [tapRecognizer locationOfTouch : 0
                                                            inView : self.view];
        CGPoint sceneTouchLocation = [self convertPointFromView : viewTouchLocation];
        // Do other stuff here
    }
}

需要注意的一件有趣的事情是，点击和平移手势识别器都不正确。它不是一个或另一个。这使我相信存在一些系统性问题。

（或者，更有可能是我搞砸了。）

有什么想法吗？

Answer 1

有时模拟器认为您按住 Option (⌥) 键并卡住，这意味着捏合手势助手在屏幕上被激活。要停止此操作，只需再次按 Option。如果这不起作用，请尝试按 Command。