問題描述

我找不到任何合乎邏輯的解釋，但事實仍然是，在 iOS 5 (xCode 4.2) 中，如果我 presentModalView:* animated:YES，我可以調(diào)用dismissModalViewAnimated:* 很好，但如果我調(diào)用 presentModalView:*動畫:否，然后調(diào)用解除方法崩潰.(如果我使用新的 presentViewController:animated:completion:+dismissViewControllerAnimated:)，這同樣適用.我現(xiàn)在要嘗試解決這個問題(我不希望演示文稿動畫化)并向Apple報告一個錯誤，但我一直在努力解決這個問題.歡迎任何和所有建議.iOS 5 上沒有多少，所以如果可以，請?zhí)峁椭?在 iOS 4 或 iOS 5 中不會崩潰的示例代碼:

I can't find any logical explanation, but the fact remains that, in iOS 5 (xCode 4.2), if I presentModalView:* animated:YES, I can call dismissModalViewAnimated:* fine, but if I call presentModalView:* animated:NO, then calling the dismiss method crashes. (This works the same if I use the new presentViewController:animated:completion: + dismissViewControllerAnimated:). I am going TRY to work around this for now (I don't want the presentation animated) and report a bug to Apple, but I have been beating my head on this for a while. Any and all suggestions are welcome. Not much out there on iOS 5, so please help if you can. Sample code that does not crash in iOS 4 or iOS 5:

LoginController *loginController = [[LoginController alloc] initWithNibName:@"LoginControllerGG" bundle:nil];
[self presentModalViewController:loginController animated:YES];
[loginController release];
...
[self dismissModalViewControllerAnimated:YES];

這將在 iOS 5 中崩潰，并在解除調(diào)用時出現(xiàn) EXC_BAD_ACCESS:

This will crash in iOS 5 with EXC_BAD_ACCESS on the dismiss call:

LoginController *loginController = [[LoginController alloc]    initWithNibName:@"LoginControllerGG" bundle:nil];
[self presentModalViewController:loginController animated:NO];
[loginController release];
...
[self dismissModalViewControllerAnimated:YES]; //crashes with EXC_BAD _ACCESS

注意:我在 loginController 中有一個動畫，它發(fā)生在 viewDidLoad 上.去看看把它拿出來是否會改變?nèi)魏螙|西，但我想把它拿出來，因為我需要盡快找到解決方案.

One note: I have an animation within the loginController that happens on viewDidLoad. Going to see if taking that out changes anything, but I wanted to get this out there since I need a solution asap.

完整代碼流程...在 AppDelegate 中，application:didFinishLaunchingWithOptions:

Full code flow... In AppDelegate, application:didFinishLaunchingWithOptions:

if (!loggedIn)  [myViewController showLoginPanel];

在 myViewController 中:

In myViewController:

- (void)showLoginPanel {    
    LoginController *loginController = [[LoginController alloc] initWithNibName:@"LoginControllerGG" bundle:nil];
    if ([self respondsToSelector:@selector(presentViewController:animated:completion:)]) {
        [self presentViewController:loginController animated:NO completion:nil];
    } else {
        [self presentModalViewController:loginController animated:NO]; //iOS 4 works fine with or without animation   
    } 
    [loginController release];  
}

在登錄控制器中:

- (IBAction)closeLoginWindow {
    [[NSNotificationCenter defaultCenter] postNotificationName:@"CloseLoginWindow" object:nil];
}   //doing it this way because calling on the self.parentViewController doesn't work

返回 myViewController:

Back in myViewController:

- (void) viewDidLoad
    ...
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(closeLoginWindow) name:@"CloseLoginWindow" object:nil];
    ...

- (void)closeLoginWindow {
    if ([self respondsToSelector:@selector(dismissViewControllerAnimated:completion:)]) {
        [self dismissViewControllerAnimated:YES completion:nil];    //iOS 5 crashes only if presentation was not animated
    } else [self dismissModalViewControllerAnimated:YES];    //deleting the previous condition, iOS 5 still crashes if presentation was not animated
}    

推薦答案

在 iOS5 中，生命周期的管理發(fā)生了某種變化，我無法詳細解釋這個問題.無論如何，解決方法是將工作流從 applicationDidFinishLaunchingWithOptions 推遲到 applicationDidBecomeActive.似乎在調(diào)用 applicationDidFinishLaunchingWithOptions 時沒有正確初始化某些內(nèi)容.

In iOS5 the managing of the lifecyle somehow changed and I cannot explain that issue in detail. Anyway, the fix is to postpone that workflow from applicationDidFinishLaunchingWithOptions to applicationDidBecomeActive. It seems that something isn't initialized right at the call of applicationDidFinishLaunchingWithOptions.

- (void)applicationDidFinishLaunchingWithOptions:... {    
    // in order to do this only at launching, but not on every activation 
    // Declaration as property for example
    applicationDidLaunch = YES;
}

- (void) applicationDidBecomeActive:(UIApplication *)application {
    if (applicationDidLaunch) {
        applicationDidLaunch = NO;
        [Start your login Workflow with modal view presenting here]
    }
}

很好奇你的反饋:)....

Curious to ur feedback :)....

這篇關(guān)于dismissModalViewControllerAnimated:(和dismissViewControllerAnimated)在iOS 5中崩潰的文章就介紹到這了，希望我們推薦的答案對大家有所幫助，也希望大家多多支持html5模板網(wǎng)！