objective-c - 来自字符串的 UIControlEvents 变量

Question

是否可以创建 UIControlEvents来自 NSString 的变量或类似的？例如，我可能有一个 NSString那叫UIControlEventTouchUpInside这与 UIControlEvents 的类型定义之一相同变量。

感谢大家的帮助!

Answer 1

如果我理解这是如何正确工作的，UIControlEvents 的枚举如下:

enum {
   UIControlEventTouchDown           = 1 <<  0,
   UIControlEventTouchDownRepeat     = 1 <<  1,
   UIControlEventTouchDragInside     = 1 <<  2,
   UIControlEventTouchDragOutside    = 1 <<  3,
   UIControlEventTouchDragEnter      = 1 <<  4,
   UIControlEventTouchDragExit       = 1 <<  5,
   UIControlEventTouchUpInside       = 1 <<  6,
   UIControlEventTouchUpOutside      = 1 <<  7,
   UIControlEventTouchCancel         = 1 <<  8,

   UIControlEventValueChanged        = 1 << 12,

   UIControlEventEditingDidBegin     = 1 << 16,
   UIControlEventEditingChanged      = 1 << 17,
   UIControlEventEditingDidEnd       = 1 << 18,
   UIControlEventEditingDidEndOnExit = 1 << 19,

   UIControlEventAllTouchEvents      = 0x00000FFF,
   UIControlEventAllEditingEvents    = 0x000F0000,
   UIControlEventApplicationReserved = 0x0F000000,
   UIControlEventSystemReserved      = 0xF0000000,
   UIControlEventAllEvents           = 0xFFFFFFFF
};

再一次，如果我理解正确的话，请纠正我，但你应该能够创建一个变量整数并将其传递给控制事件，如下所示:

    int myVariable = 64;
    [myButton addTarget:self action:@selector(mySelector) forControlEvents:myVariable];

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