warning:performSelector may cause a leak because... 忽略此警告方法
在ARC项目中使用 performSelector: withObject:
函数出现“performSelector may cause a leak because its selector is unknown”。
在stackoverflow找到了一个解决方案,地址:http://stackoverflow.com/questions/7017281/performselector-may-cause-a-leak-because-its-selector-is-unknown。
解决办法1:
宏定义忽略警告
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:
#pragma clang diagnostic push #pragma clang diagnostic ignored "-Warc-performSelector-leaks" [self.ticketTarget performSelector: self.ticketAction withObject: self];//此处是你调用函数的地方 #pragma clang diagnostic pop
如果在程序中多处使用,可以写一个宏定义,如下:
#define SuppressPerformSelectorLeakWarning(Stuff) \ do { \ _Pragma("clang diagnostic push") \ _Pragma("clang diagnostic ignored \"-Warc-performSelector-leaks\"") \ Stuff; \ _Pragma("clang diagnostic pop") \ } while (0) 如果没有返回结果,可以直接按如下方式调用:
SuppressPerformSelectorLeakWarning(
[_target performSelector:_action withObject:self]
);
如果要返回结果,可以按如下方式调用:
id result; SuppressPerformSelectorLeakWarning( result = [_target performSelector:_action withObject:self] );
解决办法2:
使用函数指针方式
SEL selector = NSSelectorFromString(@"someMethod"); IMP imp = [_controller methodForSelector:selector]; void (*func)(id, SEL) = (void *)imp; func(_controller, selector);
当有额外参数时:如:
SEL selector = NSSelectorFromString(@"processRegion:ofView:"); IMP imp = [_controller methodForSelector:selector]; CGRect (*func)(id, SEL, CGRect, UIView *) = (void *)imp; CGRect result = func(_controller, selector, someRect, someView);
解决办法3:
使用函数指针方式
[self performSelector:aSelector withObject:nil afterDelay:0.0];
如果在接受范围内,允许在下一个runloop执行,可以这么做。xCode5没问题, xCode6不能消除这个警告。