Strange warning dismissing modal view controller - iphone

Question

I'm working on iOS 6.
My application has a standard navigation controller with embedded a CustomViewController.
In this controller I create a modal view like this:
-(IBAction)presentModalList:(id)sender {
UIStoryboard *storyboard = [UIStoryboard storyboardWithName:#"MainStoryboard" bundle:nil];
StationsListViewController *list = [storyboard instantiateViewControllerWithIdentifier:#"StationsListViewController"];
[list setStationsData: [self.stationsData allValues]];
[self presentModalViewController:list animated:YES];
}
The modal controller show perfectly but dismissing generates a warning.
The dismiss method in this controller is:
-(IBAction)backToMap
{
[self dismissModalViewControllerAnimated:YES];
}
The warning generated is Warning:
Attempt to dismiss from view controller < UINavigationController: 0x1ed91620 > while a presentation or dismiss is in progress!
Any clues about that?
Thanks

Answer 1

I realise this is a late answer but maybe this will help someone else looking for a solution to this, here is what I did:
-(IBAction)backToMap
{
if (![[self modalViewController] isBeingDismissed])
[self dismissModalViewControllerAnimated:YES];
}
For me, i found that line of code was being called multiple times, I couldn't find out why so this was the easiest fix.

Answer 2

Thanks JDx for getting me on the right track. I adapted it to form this solution, which will remove the warning without using functions that are deprecated in iOS 6:
-(IBAction)backToMap
{
if (![self.presentedViewController isBeingDismissed]) {
[self dismissViewControllerAnimated:YES completion:^{}];
}
}

Answer 3

Targeting iOS6, this is what worked for me:
if (![self.presentedViewController isBeingDismissed])
[self.presentedViewController dismissViewControllerAnimated:YES
completion:nil];

Answer 4

I found this approach to be unreliable - say one case in five I'd still see the error.
My solution was to use the completion block to set a flag which controls whether or not it's safe to dismiss - that way you don't need to check whether or not the view is being dismissed.
-(IBAction)presentModalView:(id)sender {
:
self.canDismiss = NO;
[self presentViewController:aVC animated:YES completion:^{
self.canDismiss = YES;
}];
:
}
In the bit of code where the dismiss occurs, just check the flag:
-(void)dismisser {
:
if (self.canDismiss) {
[self dismissViewControllerAnimated:YES completion:nil];
}
:
}
Hey presto, no more errors!

Answer 5

You can do whatever you want after the completion of the dismiss method as:
-(IBAction)backToMap
{
[self dismissViewControllerAnimated:YES
completion:^{
//Do something here
}];
}