warning:performSelector may cause a leak because its selector is unknown

在使用 performSelector: withObject: 函数出现“performSelector may cause a leak because its selector is unknown”。

主要是警告信息，在非ARC项目中没有这个警告。如果是在某一处修改只需要加入下列代码

[code=objc]

#pragma clang diagnostic push

#pragma clang diagnostic ignored "-Warc-performSelector-leaks"

            [vcappear performSelector:selectorwithObject:nil];

#pragma clang diagnostic pop

[/code]

如果在程序中多次使用可以设置一下宏

[code=objc]

#define SuppressPerformSelectorLeakWarning(Stuff) \

do { \

_Pragma("clang diagnostic push") \

_Pragma("clang diagnostic ignored \"-Warc-performSelector-leaks\"") \

Stuff; \

_Pragma("clang diagnostic pop") \

} while (0)

[/code]

如果没有返回值

[code=objc]

        SuppressPerformSelectorLeakWarning(

          [_target performSelector:_action withObject:self]

                                               );

[/code]

有返回值

[code=objc]

       

            id result;

            SuppressPerformSelectorLeakWarning(

              result = [_target performSelector:_action withObject:self]

                                               );

[/code]