IOS 避免self循環(huán)引用的方法的實(shí)例詳解
示例代碼:
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// - weak & strong #define myWeakify(VAR) \ try {} @finally {} \ __weak __typeof__(VAR) VAR##_myWeak_ = (VAR) #define myStrongify(VAR) \ try {} @finally {} \ __strong __typeof__(VAR) VAR = VAR##_myWeak_ #define myStrongifyRetVIfNil(VAR, RET) \ try {} @finally {} \ __strong __typeof__(VAR) VAR = VAR##_myWeak_;\ if (VAR == nil) return RET #define myStrongifyRetNIfNil(VAR) \ try {} @finally {} \ __strong __typeof__(VAR) VAR = VAR##_myWeak_;\ if (VAR == nil) return |
使用如下:
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- ( void )handleFromVC { NSArray *viewControllers = self.navigationController.viewControllers; @myWeakify(self); [viewControllers enumerateObjectsWithOptions:NSEnumerationReverse usingBlock:^(id _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) { @myStrongifyRetNIfNil(self); //代碼 }]; } |
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原文鏈接:http://blog.csdn.net/robinson_911/article/details/73471384