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Question

我正在使用以下代码来显示警报控制器，但有时它会收到上述消息并且警报控制器会停止响应。这是什么意思？固定？

+(void)showAlertFor:(UIViewController *)viewController Title:(NSString*)title WithMessage:(NSString *)message 
{ 

    UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"Error" message:message preferredStyle:UIAlertControllerStyleAlert]; //Getting the alert view controller 
    UIAlertAction* ok = [UIAlertAction actionWithTitle:@"OK" style:UIAlertActionStyleDefault handler:^(UIAlertAction *action) { 

    }]; 

    [alertController addAction:ok]; 

    [viewController presentViewController:alertController animated:YES completion:nil]; 
} 

Answer 1

试试这个

+(void)showAlertFor:(UIViewController *)viewController withTitle:(NSString*)title withMessage:(NSString *)message { 

    UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"Error" message:message preferredStyle:UIAlertControllerStyleAlert]; //Getting the alert view controller 
    UIAlertAction* ok = [UIAlertAction actionWithTitle:@"OK" style:UIAlertActionStyleDefault handler:^(UIAlertAction *action) { 

    }]; 

    [alertController addAction:ok]; 
    dispatch_async(dispatch_get_main_queue(),^{ 
    [viewController presentViewController:alertController animated:YES completion:nil]; 
    }); 
} 

调用它的主线程将解决你的问题。并确保你没有在同一时间出示任何其他控制器。