我想在 swift 中做一些事情,但我不知道如何实现它,那就是删除给定类类型的手势识别器,这是我的代码(和示例),我在 Xcode 7 beta 中使用 swift 2.0 5:
我有 3 个继承自 UITapGestureRecognizer 的类
class GestureONE: UIGestureRecognizer { /*...*/ }
class GestureTWO: UIGestureRecognizer { /*...*/ }
class GestureTHREE: UIGestureRecognizer { /*...*/ }
将它们添加到视图中
var gesture1 = GestureONE()
var gesture11 = GestureONE()
var gesture2 = GestureTWO()
var gesture22 = GestureTWO()
var gesture222 = GestureTWO()
var gesture3 = GestureTHREE()
var myView = UIView()
myView.addGestureRecognizer(gesture1)
myView.addGestureRecognizer(gesture11)
myView.addGestureRecognizer(gesture2)
myView.addGestureRecognizer(gesture22)
myView.addGestureRecognizer(gesture222)
myView.addGestureRecognizer(gesture3)
我打印对象:
print(myView.gestureRecognizers!)
// playground prints "[<__lldb_expr_224.TapONE: 0x7fab52c20b40; baseClass = UITapGestureRecognizer; state = Possible; view = <UIView 0x7fab52d259c0>>, <__lldb_expr_224.TapONE: 0x7fab52d21250; baseClass = UITapGestureRecognizer; state = Possible; view = <UIView 0x7fab52d259c0>>, <__lldb_expr_224.TapTWO: 0x7fab52d24a60; baseClass = UITapGestureRecognizer; state = Possible; view = <UIView 0x7fab52d259c0>>, <__lldb_expr_224.TapTWO: 0x7fab52c21130; baseClass = UITapGestureRecognizer; state = Possible; view = <UIView 0x7fab52d259c0>>, <__lldb_expr_224.TapTWO: 0x7fab52e13260; baseClass = UITapGestureRecognizer; state = Possible; view = <UIView 0x7fab52d259c0>>, <__lldb_expr_224.TapTHREE: 0x7fab52c21410; baseClass = UITapGestureRecognizer; state = Possible; view = <UIView 0x7fab52d259c0>>]"
我用通用函数做了这个扩展
extension UIView {
func removeGestureRecognizers<T: UIGestureRecognizer>(type: T.Type) {
if let gestures = self.gestureRecognizers {
for gesture in gestures {
if gesture is T {
removeGestureRecognizer(gesture)
}
}
}
}
}
然后我用它
myView.gestureRecognizers?.count // Prints 6
myView.removeGestureRecognizers(GestureTWO)
myView.gestureRecognizers?.count // Prints 0
正在删除所有手势 D:
这是一个自定义类的实验
//** TEST WITH ANIMALS*//
class Animal { /*...*/ }
class Dog: Animal { /*...*/ }
class Cat: Animal { /*...*/ }
class Hipo: Animal { /*...*/ }
class Zoo {
var animals = [Animal]()
}
var zoo = Zoo()
var dog1 = Dog()
var cat1 = Cat()
var cat2 = Cat()
var cat3 = Cat()
var hipo1 = Hipo()
var hipo2 = Hipo()
zoo.animals.append(dog1)
zoo.animals.append(cat1)
zoo.animals.append(cat2)
zoo.animals.append(cat3)
zoo.animals.append(hipo1)
zoo.animals.append(hipo2)
print(zoo.animals)
//playground prints "[Dog, Cat, Cat, Cat, Hipo, Hipo]"
extension Zoo {
func removeAnimalType<T: Animal>(type: T.Type) {
for (index, animal) in animals.enumerate() {
if animal is T {
animals.removeAtIndex(index)
}
}
}
}
zoo.animals.count // prints 6
zoo.removeAnimalType(Cat)
zoo.animals.count // prints 3
它实际上是删除了它应该删除的类:D
UIGestureRecognizer 缺少什么?我最终找到了一个解决方法,创建一个没有泛型(无聊)的函数,如下所示:
extension UIView {
func removeActionsTapGestureRecognizer() {
if let gestures = self.gestureRecognizers {
gestures.map({
if $0 is ActionsTapGestureRecognizer {
self.removeGestureRecognizer($0)
}
})
}
}
}
这当然有效,但我仍然希望有一个真正的解决方案
我感谢您的帮助!!
注意:我在这里问的第一个问题