I am creating an app where if something occurs, it switches back to the previous screen.
There is practically no real code in the app, and when it does it has nothing to do with the previous view, but just in case, here is the entire .m: http://pastie.org/4111440
[self.navigationController popViewControllerAnimated:YES];
This^^ gives me EXC_BAD_ACCESS with "nested pop animation can result in corrupted navigation bar"
If you need any more info leave a comment. Thank you!
If you really want to help, I will message you a link to the entire .xcodepproj or whatever the extention is for the entire product.
I think the message says it all: "nested pop animation can result in corrupted navigation bar".
It looks like you are doing a pop with animation while in the middle of doing a pop with animation. I would recommend you figure out a different way to structure the code so you don't have the double pop.
If that's not possible, you may want to do a delayed pop to keep them from overlapping.
- (void)doPop
{
[self.navigationController popViewControllerAnimated:YES];
}
…
// At the previous pop point.
[self performSelector:#selector(doPop) withObject:nil afterDelay:0.5];
I have a view which is presented as a modal view controller which takes username and password credentials. I want this view to check the delegate, and if the user hasn't previously set an unlock pin for the app, to then show the change pin view as a modal view controller. This is my code...
+(void)presentCredentialsViewController:(UIViewController *)vc{
CredentialsViewController *cvc = [[CredentialsViewController alloc] init];
[vc presentModalViewController:cvc animated:FALSE];
}
and then in CredentialsViewController
-(void)viewDidLoad{
[super viewDidLoad];
if([appDelegate.pin isEqualToString: #""]){
UserPrefsViewController *upvc = [[UserPrefsViewController alloc] init];
upvc.cancelButton.hidden = true;
[self presentModalViewController:upvc animated:FALSE];
}
}
But for some reason it doesn't work. The debugger steps through the code without error, never the less, the second modal view controller isn't displayed.
First, I would suggest checking that your appDelegate.pin is blank and not nil. If it is nil, the if statement would not be satisfied and your second ModalView would not be presented.
You may also want to try the previous suggestion, calling presentModalViewController from viewDidAppear, or setting a delay if leaving it in viewDidLoad. It is possible that the CredentialsViewController is trying to present the second view when it has not yet presented itself.
The if statement is being hit and the second PresentModalViewController is executing without error, but it just wasn't displaying. I did try putting the code in ViewDidAppear and a load of other places as well, such as applicationWillBecomeActive etc. Although not actually crashing the code, still none of these approaches would show the view controller. In the end I have opted for this:
start with pin of #""
on applicationDidEnterBackground check if pin has been set
if yes
PresentModalViewController: PinViewController
if no
do nothing
Bit of a hack but it will do for now. I suppose I should put some sort of notification in somewhere warning that the pin hasn't been set. The suggestion about the delay may possibly work I suppose. I might give it a go in the future. Thanks guys....points up!
I keep getting the following errors:
2011-04-02 14:55:23.350 AppName[42430:207] nested push animation can result in corrupted navigation bar
2011-04-02 14:55:23.352 AppName[42430:207] nested push animation can result in corrupted navigation bar
2011-04-02 14:55:23.729 AppName[42430:207] Finishing up a navigation transition in an unexpected state. Navigation Bar subview tree might get corrupted.
2011-04-02 14:55:23.729 AppName[42430:207] Finishing up a navigation transition in an unexpected state. Navigation Bar subview tree might get corrupted.
Here is what I am doing. From a view controller, I call the following when a certain button is pushed:
EventsViewController *viewController = [[EventsViewController alloc] init];
UINavigationController *navController = [[UINavigationController alloc] initWithRootViewController:viewController];
navController.navigationBar.tintColor = [UIColor blackColor];
[self presentModalViewController:navController animated:YES];
[viewController release];
[navController release];
Then, if a certain button is pushed in EventsController, I call:
SingleEventViewController *viewController = [[SingleEventViewController alloc] initWithEvent:[currentEvents objectAtIndex:indexPath.row]];
[self.navigationController pushViewController:viewController animated:YES];
[viewController release];
Then, if a certain button is pushed in SingleEventViewController, I call:
EventMapView* viewController = [[EventMapView alloc] initWithCoordinates];
[[self navigationController] pushViewController:viewController animated:YES];
[viewController release];
So yea, it's obvious that there's nested push animations, but isn't this the right way to go about it? I checked out Apple's DrillDownSave code and this appears to be how they're doing it. Does it matter that I use init methods instead of viewDidLoad methods?
Calling pushViewController before viewDidAppear is unsafe.
ACCIDENTLY TRIGGERING THE SAME SEGUE TWICE
Once in code, and once from interface builder, but both at the same time...
I was getting the same error as the rest of you. Only my problem was I was accidentally firing the same segue, twice. Once from interface builder, and once from within my code.
I have a UITableView. When a cell is selected, a segue in interface builder fires. Heres my problem, I had the segue set up to be directly fired off clicking the CELL ITSELf, inside interface builder, then in my code, I had under didSelectRowAtIndexPath, code that would fire that same segue... like so...
[self performSegueWithIdentifier:#"MySegue" sender:tableView];
That means when didSelectRowAtIndexPath gets called because a row was selected, it fires the segue with the above line of code. Then interface builder, also triggers the segue, because its connected directly to the cell object in interface builder. To stop interface builder from directly firing the segue. You have to connect the segue from the top of the view controller, not nested down inside coming off of the cell itself.
So if you are having this problem for the same reason as me, that is, you are calling the same segue twice, you can fix this by unlinking the connection from the CELL DIRECTLY, to your segue, and having the segue connection originate at the top of the table hierarchy in IB, rather than nested inside the cell. Connect the segue from you View Controller itself, to the segue. If you have done this correct, when you select the segue, it should highlight the ENTIRE view it is coming from, not just the cell.
Now Apples documentation states thus under the performSegueWithIdentifier:sender: reference:
Apps normally do not need to trigger segues directly. Instead, you configure an object in Interface Builder associated with the view controller, such as a control embedded in its view hierarchy, to trigger the segue. However, you can call this method to trigger a segue programmatically, perhaps in response to some action that cannot be specified in the storyboard resource file. For example, you might call it from a custom action handler used to process shake or accelerometer events.
In my case, I have a search button for my UITableView, and whether the segue is called when the search results table is present, or the normal table view is present, had to be determined. So I needed to trigger the segue directly.
So remove the embedded control from interface builder, and just stick it on the view controller itself, then trigger the segue in your code!
Now, no more double segues! And no more errors.
I had the same problem / error message as you did just now, was looking for a solution and ended up at this thread, however, for me I found that the solution is actually having only one animated:YES when doing a nested push (I put animated:YES only for the final push), hope this helps
cheers.
I've figured it out. Apparently if you call -pushViewController from outside of the -didSelectRowAtIndexPath method of a UITableViewDelegate, it doesn't work. Moving the call into that function worked. Weird.
I happened upon this same problem that resulted from a button in a nib being connected to two different actions. It tried loading both view controllers, thereby corrupting the stack.
What do you mean when you say you use init methods instead of viewDidLoad methods?
If you're pushing a new view controller before the old push has bad a chance to be actioned, you will get this sort of error. So putting certain code into init and doing things prematurely could certainly get you the error being reported.
At the point where init is being run on a view controller, the view hasn't been loaded yet!
Um I had this issue, and Im new to the whole iOS dev scene. But after looking at my connections inspector (with file's owner) in the interface builder i saw that as I had copied a button it had the previous buttons method assigned to it as well as the new method I had created. I guess that was where the nested aspect of my problem came from, as it was executing 2 different methods both of which pushed a view onto the Nav Controller. I know this has already been answered but I figured I would put this up just in case anyone else had a silly mistake like mine.
This has already been answered, but I thought this might help others as I got the same error but without using table views. I finally figured out the problem.
I had an existing button whose IBAction invoked a pushViewController. I had created a new button by copying the existing button. The new button also had an action that invoked pushViewController. When the new button was tapped (touch up inside) and the view controller was pushed, I got this error. I deleted the new button, created it from scratch, bound it to the existing outlets and actions, and the error went away.
Ran into the same problem. In my case I was missing a break in the switch statement so two segues were fired at the same time. Easy fix for me.
My problem had to do with the keyboard being active.
This was caused for me by pushing a ViewController from a textField's delegate method:
-(void)textFieldDidBeginEditing:(UITextField *)textField{
FilterLocationViewController *destViewController = (FilterLocationViewController *)[self.storyboard instantiateViewControllerWithIdentifier:#"FilterLocationViewController"];
[self.navigationController pushViewController:destViewController animated:YES];
}
By changing the code to this:
-(void)textFieldDidBeginEditing:(UITextField *)textField{
[_textFieldLocation resignFirstResponder]; //adding this line
FilterLocationViewController *destViewController = (FilterLocationViewController *)[self.storyboard instantiateViewControllerWithIdentifier:#"FilterLocationViewController"];
[self.navigationController pushViewController:destViewController animated:YES];
}
(adding the line [textField resignFirstResponder];) the problem went away.
Basically the lesson is that you shouldn't modify the navigationController stack if the keyboard is out.
Recently, I've faced the same problem. The reason was: -I was trying to pop view controller twice by mistake. you can check this crash by setting breakpoints on push and pop View controllers
1) Perhaps you could try passing the necessary variables as properties before pushing the UIViewController rather than using the init methods with parameters. Most likely you will need these parameters beyond your init method anyway.
Also, in your initWithCoordinates: method you are missing the parameters. Possibly your custom init methods are a part of the problem.
2) Just because you mentioned viewDidLoad -- this method is for initialization after a view has loaded . If you create the UIViewController in code, as it seems you do, you should use loadView to set up your subviews.
This was happening for me because of my UIControlEvents
[button addTarget:self action:#selector(callSecondView) forControlEvents:UIControlEventAllTouchEvents];
I had to change the UIControlEventAllTouchEvents to UIControlEventTouchUpInside or however you want your button to work if you had the issue because of a UIButton call.
My Solution was
[self performSelector:#selector(moveTo) withObject:nil
afterDelay:0.5];
Don't know about other's. I think most of the People using StoryBoard is facing such Problem. I am using XIB.
In my case The Problem Was, when I was moving to another view using push,
I was also using
[self.navigationController popViewControllerAnimated:YES];
in the ViewWillDisappear of the current View at the same time. Just remove it and it works fine.
I was using POP, because of the requirement and the Flow.
The Hierarchy was 1 -> 2 ->3
I was on view 2 and wanted to move to view 3. In that case I encountered this error.
In my case I was both setting the push segue from the storyboard and programatically. Hopefully that'll help anyone
I had this error message too, and the navigation bar and navigation controller transitions were weird. My setup was a bunch of Navigation Controllers embedded in a Tab bar Controller. The problem was that I didn't call super.viewDidLoad() in my Tab bar Controller implementation of viewDidLoad.
Calling super is something the docs clearly point out that you should do when overriding viewDidLoad, and I learned this the hard way.
Maybe this can help someone else too!
I know that this was answered, but it could help others.
I had the same problem, but it was caused because I was using a bad event for an info button.
I was using "UIControlEventAllTouchEvents" and this generated two push of the same view into the navigation controller. The correct event was "UIControlEventTouchUpInside". I'm new to iOS.
This resolves the problem:
https://github.com/nexuspod/SafeTransition
If you push (or pop) a view controller with animation(animated:YES) it doesn't complete right away, and bad things happen if you do another push or pop before the animation completes.
To reproduce this bug, try pushing or popping two view controllers at the same time. Example:
- (void)viewWillAppear:(BOOL)animated
{
[super viewWillAppear:animated];
UIViewController *vc = [[UIViewController alloc] init];
[self.navigationController pushViewController:vc animated:YES];
}
You will receive this error:
2014-07-03 11:54:25.051 Demo[2840:60b] nested push animation can
result in corrupted navigation bar 2014-07-03 11:54:25.406
Demo[2840:60b] Finishing up a navigation transition in an unexpected
state. Navigation Bar subview tree might get corrupted.
Just add the code files into your project and makes your navigation controller as a subclass of APBaseNavigationController, and you'll be good to do.
Just to complete the list, here is another reason which can cause "nested push animation can result in corrupted navigation bar":
I did setup several NavigationController within a TabBarController and set
the selectedIndex within the storyboard Identifiy Properties. After moving active Tab to Code error disappeared.
I have a situation where I want to open one modal controller from the other. But when the user closes either, they should go back to the parent controller of both modal controllers.
So I have the parent controller in charge of this. The method on the parent does something similar to the code below when the user clicks a button on the first modal controller.
[self.navigationController dismissModalViewController:YES];
SecondModalViewController *c = [[SecondModalViewController alloc] init];
[self.navigationController presentModalViewController:c animated:YES];
[c release];
The only thing that happens is the first view closes, but I don't see the second view open. Is it possible to close a modal ViewController and open a second one in the same method? If so, how?
i think that by the time you close the first view controller, the [self.navigation presentmodal..] dosen't have a self to open the new one from.
you could do that:
use a boolean variable to state whether the next time this controller appears (when you close the one you're currently trying to open), it should close, and implements that feature in the viewDidApper: method, like so:
#interface FirstViewController : UIViewController
{
//...
BOOL close;
}
and in the .m file,
-(void)viewDidAppear:(BOOL)animated{
if(close)
[self dismissModalViewControllerAnimated:NO];
else
[super viewDidAppear:animated];
}
now, to open your new controller, do that:
-(IBAction)openSecondController:(id)sender{
//..
SecondViewController* controller = [[SecondViewController alloc] initWithNibName:#"SecondViewController" bundle:nil];
close = YES;
[self presentModalViewController:controller animated:NO];
}
now, when you close the second one, the first one will close also. doesn't have any visible side affects in my apps..
not the cleanest way, but i didn't find a better one.
cheers
I do that same thing all the time without a problem, though mine have animated:NO... I'm guessing your issue is because you have animated:YES on both. What effect are you looking for exactly? Do you want to see one get animated away, and then the other get animated in? If so, you need to execute the presentModalViewController with a delay.
Otherwise, you should just be able to present the second modal view controller without closing the first one at all. When you call dismissModalViewController; it should dismiss both.
I'm finding exactly the same response. It looks like standard behaviour.
The way I got around it is to use performSelector:withObject:afterDelay:
[self performSelector:#selector(presentController:) withObject:navController afterDelay:0.5f];
The only drawback was I had to set a presentController function which then did the presentModalViewController:animated:
I tried to use a NSInvocation but I kept on getting a bad access error when I tried to pass a BOOL for the animated argument.
The main thing is it works and my client is happy.
You can use handle uiviewcontroller closed and open another with using Unwind Segues.
https://developer.apple.com/library/content/technotes/tn2298/_index.html
I am a relatively new iPhone app developer so my knowledge is a little sketchy, so please forgive me if this is a bit of a trivial question.
I have a navigation app which drills between table views by calling pushViewController on the navigationController object
I have one particular section which pushes new view controllers sequentially as the user goes through the interface. The view controllers are all subclassed from UIViewController.
It all works fine until it gets to the end, where the idea is the user presses a "Finish" button and is returned to the root view controller (main menu).
So on the button press I call:
[[self navigationController] popToRootViewControllerAnimated:YES];
And it crashes.
I am a bit worried this could be a big problem as this definitly worked at some point but it is now always failing.
Can anyone give any ideas/advice?
Some suggestions:
Before calling popToRootViewControllerAnimated: confirm that the RootViewController does actually exist. If it died somewhere along the line, calling the method will cause a crash.
Check the – viewWillDisappear: and – viewDidDisappear: methods of your last view to make sure you're not doing something dangerous there.
Not sure if popping a view causes it to always deallocate but check the dealloc method of the views and their controllers to make sure your not over-releasing something.
One mistake I've seen a lot is releasing objects in the data model from controllers. When another controller (in this case the RootViewController) tries to access the data model the app crashes.
It sound's like you need how to use the Xcode debugger. Type in debugger in Xcode help to get pointers.
You should not be using popToRootViewController in your viewWillDisappear.
Instead if you want to pop to root controller on your pressing the back button, you should replace the back button by your own and add an action to it. Try doing something like ::
UIBarButtonItem *back = [[UIBarButtonItem alloc] initWithTitle:#"back"
style:UIBarButtonItemStyleBordered
target:self
action:#selector(goBack:)];
self.navigationItem.leftBarButtonItem = back;
and then handle the action as ::
- (void) goBack:(id)sender
{
// pop to root view controller
[self.navigationController popToRootViewControllerAnimated:YES];
}
As the others have commented, the first step is to run this is debug mode and figure out where and why you are crashing.
The most common type of crash is using a deallocated object (EXEC_BAD_ACCESS). Have you run the static analyzer? Are you properly retaining your object references?