Quick question:
If I use
[someViewController.view addSubView:otherViewController.view];
to add a view. And then use
[otherViewController.view removeFromSuperView]
to remove the view, my app will crash when I call [otherViewController release]
The crash point is in the [super dealloc]
line in my dealloc
method of otherViewControll
class implementation.
otherViewController is a reference to the view controller. I call release after its view has been removeFromSuperView'ed. By the time I call release, it's a valid pointer.
What am I doing wrong here?
otherViewController's dealloc class implementation
- (void)dealloc {
[popVC release];
[photoContainer release];
[photoView release];
[recordName release];
[recordIngr release];
[recordDesc release];
[recordPrice release];
[quantity release];
[pricingLabel release];
[increaseButton release];
[decreaseButton release];
[pricingTableVC release];
[pricingTable release];
[super dealloc]; // <--- crash point
}
updated: call trace
2011-06-04 00:35:05.110 MyApp[2308:207] -[__NSCFType _viewDelegate]: unrecognized selector sent to instance 0x4b6feb0
2011-06-04 00:35:05.124 MyApp[2308:207] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSCFType _viewDelegate]: unrecognized selector sent to instance 0x4b6feb0'
*** Call stack at first throw:
(
0 CoreFoundation 0x00dd75a9 __exceptionPreprocess + 185
1 libobjc.A.dylib 0x00f2b313 objc_exception_throw + 44
2 CoreFoundation 0x00dd90bb -[NSObject(NSObject) doesNotRecognizeSelector:] + 187
3 CoreFoundation 0x00d48966 ___forwarding___ + 966
4 CoreFoundation 0x00d48522 _CF_forwarding_prep_0 + 50
5 UIKit 0x00379051 -[UIViewController dealloc] + 128
6 MyApp 0x00009b26 -[RecordDetailViewController dealloc] + 797
7 MyApp 0x00004744 __-[RecordRootViewController bringUpNextRecordDetail:isNext:]_block_invoke_2 + 77
8 UIKit 0x002f7fb9 -[UIViewAnimationState sendDelegateAnimationDidStop:finished:] + 294
9 UIKit 0x002f7e4b -[UIViewAnimationState animationDidStop:finished:] + 77
10 QuartzCore 0x01d7b99b _ZL23run_animation_callbacksdPv + 278
11 QuartzCore 0x01d20651 _ZN2CAL14timer_callbackEP16__CFRunLoopTimerPv + 157
12 CoreFoundation 0x00db88c3 __CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION__ + 19
13 CoreFoundation 0x00db9e74 __CFRunLoopDoTimer + 1220
14 Core开发者_运维技巧Foundation 0x00d162c9 __CFRunLoopRun + 1817
15 CoreFoundation 0x00d15840 CFRunLoopRunSpecific + 208
16 CoreFoundation 0x00d15761 CFRunLoopRunInMode + 97
17 GraphicsServices 0x0172e1c4 GSEventRunModal + 217
18 GraphicsServices 0x0172e289 GSEventRun + 115
19 UIKit 0x002d5c93 UIApplicationMain + 1160
20 MyApp 0x0000200c main + 102
21 MyApp 0x00001f9d start + 53
)
terminate called after throwing an instance of 'NSException'
Update: in -viewDidLoad, I have a gesture recognizer:
{
UISwipeGestureRecognizer *leftSwipeGestureRecognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(showNextRecod:)];
[leftSwipeGestureRecognizer setDirection:(UISwipeGestureRecognizerDirectionLeft)];
[self.view addGestureRecognizer:leftSwipeGestureRecognizer];
[leftSwipeGestureRecognizer release];
}
I tried to use a Button to call -(IBAction) showNextRecod, it won't crash!! Only when I use the gesture to call the same method, it would crash
Regards
Leo
When you add a view controller's view as a subview to another view, you are only retaining it's view in memory and not the controller itself. Therefore, you must retain the view controller somewhere else (most likely make it a property)
Does that make sense?
In your gesture selector showNextRecod:
you should remove your target [pGestureRecognizer removeTarget:nil action:NULL];
@leo You are just adding otherViewController.view in someViewController.view.
Just adding view not allocating it, then just remove it from your view.
Im not getting why you are using [otherViewController release] when you are not allocating it same view.
For sure you can log otherViewController.view count. See how much retain count for that view you are getting.
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