ios - 执行选择器警告

Question

我收到警告

PerformSelector may cause a leak because its selector is unknown

在代码中:

- (void) callDelegate: (SEL) selector withArg: (id) arg error: (NSError*) err
{
    assert([NSThread isMainThread]);
    if([delegate respondsToSelector: selector])
    {
        if(arg != NULL)
        {
            //this line the warning
            [delegate performSelector: selector 
                           withObject: arg 
                           withObject: err]; 
        }
        else
        {
            //this line the warning
            [delegate performSelector: selector 
                           withObject: err]; 
        }
    }
    else
    {
        NSLog(@"Missed Method");
    }
}

标题:

@interface Topscore : UIViewController <NSObject> {

//
}

Answer 1

您的 if ... respondsToSelector: selector 将不起作用，因为您的 selector 只是方法的名称。对于您的情况，您需要检查

if ([delegate respondsToSelector: @selector(method::)]

另一种情况仅适用于方法:。

无论如何，你可以像这样抑制警告:

#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Warc-performSelector-leaks"
    [self performSelector:nextView];
#pragma clang diagnostic pop