swift在extension中能加属性吗

2025-04-03 07:07:05
推荐回答(1个)
回答1:

比如,我有一个ELCImagePickerController类,需要增加一个tag属性,代码如下:

import ObjectiveC

private var xoTag: UInt = 0

extension ELCImagePickerController {

var tag: UInt {
get {
return (objc_getAssociatedObject(self, xoTag) as? UInt)!
}
set(newValue) {
objc_setAssociatedObject(self, xoTag, newValue, objc_AssociationPolicy(OBJC_ASSOCIATION_RETAIN))
}
}
}