ios - popViewController Animated : from alertView:didDismissWithButtonIndex: 的断断续续的动画

Question

当它在 UIalertView 委托(delegate)方法 alertView:didDismissWithButtonIndex: 中完成时，我在方法 popViewControllerAnimated: 中遇到动画问题不稳定且快速(使用 Xcode 7.3.1)。谁能理解为什么？

- (void)alertView:(UIAlertView *)alertView didDismissWithButtonIndex:(NSInteger)buttonIndex
{
    if (buttonIndex != alertView.cancelButtonIndex)
    {
        // animation of popViewControllerAnimated: is not working correctly
        [self.navigationController popViewControllerAnimated:YES];
    }
}

奇怪的是这段代码运行没有问题:

- (void)alertView:(UIAlertView *)alertView didDismissWithButtonIndex:(NSInteger)buttonIndex
{
    if (buttonIndex != alertView.cancelButtonIndex)
    {
        // code is running om main thread
        if ([[NSThread currentThread]isMainThread])  {
            // still - by using GCD and go to main thread, the animation works!!
            dispatch_async(dispatch_get_main_queue(), ^{
                [self.navigationController popViewControllerAnimated:YES];
            });
        }
    }
}

还有这个:

- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex {

    if(buttonIndex != alertView.cancelButtonIndex)
    {
        // no problem with animation when done in alertView:clickedButtonAtIndex:
        [self.navigationController popViewControllerAnimated:YES];
    }
}

我知道 UIAlertView 已被弃用一段时间了，可能是因为这个原因吗？自 2012 年以来，该代码在应用程序中就没有被修改过，并且最近开始表现得很奇怪。

Answer 1

您可以尝试使用 willDismissWithButtonIndex 而不是 didDismissWithButtonIndex

- (void)alertView:(UIAlertView *)alertView willDismissWithButtonIndex:(NSInteger)buttonIndex
{
    if (buttonIndex != alertView.cancelButtonIndex)
    {
        [self.navigationController popViewControllerAnimated:YES];
    }
}

对我来说这个工作没问题!希望这对你有帮助