iOS应用崩溃显示，当键盘

Question

我们有以下的问题，这是我如何重现它：

1. 我有一个文本框在RootViewController的和viewDidLoad中我做的：

   UITextField *tf = [[UITextField alloc] initWithFrame:CGRectMake(0, 0, 200, 200)]; 
   tf.backgroundColor = [UIColor whiteColor]; 
   tf.delegate = self; 
   [self.view addSubview:tf]; 
   [tf becomeFirstResponder]; 
   

2. RootViewController有2个容器，一个用于侧边菜单，另一个用于实际的内容视图。它并委托UITextFieldDelegate和UITextViewDelegate

3. 如果我们启动应用程序的文本框正常

4. 行为通过几个视图控制器导航这样的后：

   [destination.view setFrame:[[UIScreen mainScreen] applicationFrame]]; 
   
   [self.currentVC willMoveToParentViewController:nil]; 
   [self addChildViewController:destination]; 
   
   [self transitionFromViewController:self.currentVC 
           toViewController:destination 
             duration:0.25 
             options:UIViewAnimationOptionTransitionCrossDissolve 
            animations:nil 
            completion:^(BOOL finished){ 
   
             [self.currentVC removeFromParentViewController]; 
             [destination didMoveToParentViewController:self]; 
   
             self.currentVC = destination; 
             self.currentSelection = selection; 
            }]; 
   

每当我想用显示键盘“Cmd + K”（模拟器）我得到一个EXC_BAD_ACCESS

再一次得到崩溃的唯一方法是显示系统键盘

1. 启用僵尸使它有点更好，但它最终崩溃（只有当我打开键盘）。
2. 我试着malloc的后卫，但虚拟机运行的内存，它并不能真正帮助

我出出主意！下面是跟踪：

0 0x00c1d160 in CALayerGetSuperlayer() 
1 0x00fae832 in -[UIView(Hierarchy) superview]() 
2 0x00fa144a in -[UIView nextResponder]() 
3 0x010f39f1 in -[UIResponder(Internal) _responderWindow]() 
4 0x00fbbc89 in -[UIView(Internal) _firstResponder]() 
5 0x010f25c2 in -[UIResponder isFirstResponder]() 
6 0x01748243 in -[UITextView _keyboardDidShow:]() 
7 0x0222d079 in __57-[NSNotificationCenter addObserver:selector:name:object:]_block_invoke() 
8 0x02dd8be4 in __CFNOTIFICATIONCENTER_IS_CALLING_OUT_TO_AN_OBSERVER__() 
9 0x02cc511b in _CFXNotificationPost() 
10 0x0221c5d6 in -[NSNotificationCenter postNotificationName:object:userInfo:]() 
11 0x016fe4e5 in -[UIInputWindowController postEndNotifications:withInfo:]() 
12 0x01705660 in -[UIInputWindowController keyboardHeightChangeDone]() 
13 0x0117da40 in -[UIKeyboardImpl _resizeForKeyplaneSize:splitWidthsChanged:]() 
14 0x012ebf42 in __66-[UIKeyboardPredictionView setPredictionViewState:animate:notify:]_block_invoke() 
15 0x00fb7c06 in +[UIView(UIViewAnimationWithBlocks) _setupAnimationWithDuration:delay:view:options:factory:animations:start:animationStateGenerator:completion:]() 
16 0x00fb7fc7 in +[UIView(UIViewAnimationWithBlocks) animateWithDuration:delay:options:animations:completion:]() 
17 0x012ebd31 in -[UIKeyboardPredictionView setPredictionViewState:animate:notify:]() 
18 0x012eb78a in -[UIKeyboardPredictionView setPredictionViewState:animate:]() 
19 0x01193b1a in -[UIKeyboardImpl showKeyboard]() 
20 0x01195fb0 in -[UIKeyboardImpl toggleSoftwareKeyboard]() 
21 0x01196020 in -[UIKeyboardImpl ejectKeyDown]() 
22 0x00f32920 in -[UIApplication _physicalButtonsBegan:withEvent:]() 
23 0x0269a7cd in -[NSObject performSelector:withObject:withObject:]() 
24 0x010f1c94 in forwardTouchMethod() 
25 0x010f4226 in -[UIResponder(Internal) _physicalButtonsBegan:withEvent:]() 
26 0x0269a7cd in -[NSObject performSelector:withObject:withObject:]() 
27 0x010f1c94 in forwardTouchMethod() 
28 0x010f4226 in -[UIResponder(Internal) _physicalButtonsBegan:withEvent:]() 
29 0x0269a7cd in -[NSObject performSelector:withObject:withObject:]() 
30 0x010f1c94 in forwardTouchMethod() 
31 0x010f4226 in -[UIResponder(Internal) _physicalButtonsBegan:withEvent:]() 
32 0x0269a7cd in -[NSObject performSelector:withObject:withObject:]() 
33 0x010f1c94 in forwardTouchMethod() 
34 0x010f4226 in -[UIResponder(Internal) _physicalButtonsBegan:withEvent:]() 
35 0x0176f4d3 in -[UITextField _physicalButtonsBegan:withEvent:]() 
36 0x00f8732a in -[UIWindow _sendButtonsForEvent:]() 
37 0x00f878d8 in -[UIWindow sendEvent:]() 
38 0x00f45681 in -[UIApplication sendEvent:]() 
39 0x00f55ab8 in _UIApplicationHandleEventFromQueueEvent() 
40 0x00f292e7 in _UIApplicationHandleEventQueue() 
41 0x02d3006f in __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__() 
42 0x02d25b7d in __CFRunLoopDoSources0() 
43 0x02d250d8 in __CFRunLoopRun() 
44 0x02d24a5b in CFRunLoopRunSpecific() 
45 0x02d2488b in CFRunLoopRunInMode() 
46 0x058352c9 in GSEventRunModal() 
47 0x05835106 in GSEventRun() 
48 0x00f2d0b6 in UIApplicationMain() 
49 0x001cd8ba in main at main.m:14 
50 0x03b4cac9 in start() 

更新：我接触苹果的支持，以获得帮助，因为我一定要得到这个解决。我的想法是，我们正在做一些不好的内存管理，但Profiler不显示僵尸。尽管在ADBEncondingStringToHex中有一个内存泄漏，但无法对该信息进行任何操作。也许完全不相关，也许不是......

Answer 1

我认为在viewDidLoad中调用[tf becomeFirstResponder]为时尚早 - 在视图是应用视图层次结构的一部分之前。您应该将其称为viewWillAppear:或viewDidAppear:。

从文档：

您可能会调用该方法做出响应者的物体，如视图中的第一响应者。但是，如果它是视图层次结构的一部分，则只应在该视图上调用它。如果视图的window属性包含一个UIWindow对象，则它已安装在视图层次结构中;如果它返回nil，则该视图将从任何层次结构中分离出来。

Answer 2

这种问题发生在我以前在iOS8.xx（尽管iOS7.xx没有问题）。我通过在键盘弹出之前调用resignFirstResponder来解决它的问题，即成为第一个响应者。所以我觉得任何事情之前，你应该调用下面的代码，你TF 文本框的resignFirstResponder带出键盘：

[tf resignFirstResponder];