过载gestureRecognizerShouldBegin与UIPanGestureRecognizer在迅速

Question

我有一个平底锅的手势，我需要检查手势何时开始。在Objective-C，你可以使用

- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer 

，并有可能与UIPanGestureRecognizer

- (BOOL)gestureRecognizerShouldBegin:(UIPanGestureRecognizer *)gestureRecognizer 

但在迅疾

override func gestureRecognizerShouldBegin(gestureRecognizer: UIPanGestureRecognizer) -> Bool { 

重载它不工作，并返回

重写方法与选择器'gestureRecognizerShouldBegin：'具有不兼容的类型'（UIPanGestureReco gnizer） - > Bool'

如何在swift中重载此方法？

Answer 1

删除覆盖，不要忘记添加UIGestureRecognizerDelegate扩展。

您可以在类的底部添加它

class YourViewController: UIViewController { 
    // You class declaration 
} 

extension YourViewController: UIGestureRecognizerDelegate { 
    func gestureRecognizerShouldBegin(gestureRecognizer: UIGestureRecognizer) -> Bool { 
     // 
     return true 
    } 
} 

Answer 2

你并不需要重载的方法，你可以这样做，而不是：

override func gestureRecognizerShouldBegin(gestureRecognizer: UIGestureRecognizer) -> Bool { 
    if let panGesture = gestureRecognizer as? UIPanGestureRecognizer { 
     return ... 
    } 
    else { 
     return ... 
    } 
}