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。

posted @ 2016-01-07 17:06  ItsApe  阅读(280)  评论(0编辑  收藏  举报