IPhone - After dismissing Modal View Controller - gap is left at top of page

Question

When starting the app, if the user doesn't have login information stored, I want to display a modal view controller to force the entry of this information. I found through trial and error, that this had to occur in viewDidAppear of my root view controller. I tried to put it in viewDidLoad and viewWillAppear, but those didn't work unless I assigned the view of the root view controller to the view of the navigation controller used in the modal which then caused other issues...

So I have:

- (void)viewDidAppear:(BOOL)animated {      NewAccountViewController *newAccountViewController = [[[NewAccountViewController alloc] initWithNibName:@"NewAccountViewController" bundle:nil] autorelease];       UINavigationController *accountNavigationController = [[UINavigationController alloc] initWithRootViewController:newAccountViewController];   [self presentModalViewController:accountNavigationController animated:YES];        } 

And in the newAccountViewController I have a simple navigation item button that dismisses the modal view controller with dismissModalViewController.

This all works and when the modal is dismissed a view in a navigation controller is visible with its navigation item title at the top....

But there is a white gap about the same size as the status bar between the status bar and the top of the blue navigation item bar. If I don't do the modal, then the gap is never there. It only occurs after the modal is presented and dismissed. I've tried doing animated:NO on both the present and dismissModalViewController. I've also tried not using the navigation controller in the modal, and that did nothing as well. Any ideas would be great! Thanks.

Answer 1

I had the same problem. My solution was to temporarily close the status bar just before switching views:

- (void) temporarilyHideStatusBar {   [[UIApplication sharedApplication] setStatusBarHidden:YES];   [self performSelector:@selector(showStatusBar) withObject:nil afterDelay:0]; } - (void) showStatusBar {   [[UIApplication sharedApplication] setStatusBarHidden:NO]; }  // Use these by calling the hide function just before a broken view switch: [self temporarilyHideStatusBar]; [self doViewSwitch];  // No need to call [self showStatusBar]; explicitly. 

I experimented with other code-based solutions, and I like this one the best because it works 100% of the time - some of my frame-based solutions only worked most of the time - and because it has minimal user-visible effects.

I suspect this is an Apple bug, and it would be nice to hear the official word from them on the best workaround.

Answer 2

Turns out this was happening because I was calling my modalviewcontroller on the current view controller, but my view controller already had a another view controller loaded as a subview. Once I changed it to make the view controller in the subview, load the modal, then it went away. Thanks for all your help.