UIAlertView中崩溃

Question

我得到这个下面的例外，同时提示用户

0 CoreFoundation __exceptionPreprocess + 130 
1 libobjc.A.dylib objc_exception_throw + 38 
2 CoreFoundation -[NSObject(NSObject) doesNotRecognizeSelector:] + 202 
3 CoreFoundation ___forwarding___ + 706 
4 CoreFoundation _CF_forwarding_prep_0 + 24 
5 UIKit   -[_UIModalItem setMessage:] + 40 
6 UIKit   -[_UIModalItem initWithTitle:message:otherButtonTitles:completion:delegate:] + 102 
7 UIKit   +[_UIModalItem modalItemWithType:title:message:buttonTitles:completion:] + 76 
8 UIKit   -[UIAlertView _modalItemForNeueCompatibility] + 362 
9 UIKit   -[UIAlertView popupAlertAnimated:animationType:atOffset:] + 56 
10 UIKit   -[UIAlertView popupAlertAnimated:animationType:] + 34 

我写的警报视图代码的方法在我的实用工具类的一个

+(void)showAlertWithTitle:(NSString*)title message:(NSString*)msg cancelButtonTitle:(NSString*)canceltitle confirmBtnTitle:(NSString*)cnftitle andTag:(int)alertTag andDelegate:(id)ref{ 

    UIAlertView *alertView = [[UIAlertView alloc]initWithTitle:title message:msg delegate:ref cancelButtonTitle:canceltitle otherButtonTitles:cnftitle, nil]; 
    alertView.tag = alertTag; 
    [alertView show]; 
} 

Answer 1

，您必须出示从警报视图主线程。如果这一段代码可以潜在地从任何其他队列或线程调用，它包装在一个呼叫到dispatch_async：

dispatch_async(dispatch_get_main_queue(),^
{ 
    UIAlertView *alertView = [[UIAlertView alloc]initWithTitle:title message:msg delegate:ref cancelButtonTitle:canceltitle otherButtonTitles:cnftitle, nil]; 
    alertView.tag = alertTag; 
    [alertView show]; 
});