Problems with removing TabBarController

[SteveMobs]

Before posting (quite complex) code I would just like to say what I want to do and which problems I have.

After starting the App I would like to present a login-view. When the user presses the login button I would like to present a TabBarController with several view controllers. The user also has the chance to logout. When the logout button is pressed, the tab bar controller and all its view controllers should be unloaded/released, and the login view should be loaded again and presented.

Now I am having some serious troubles with the tab bar controller. I tried to wrap it into a separate view controller class, which has a tab bar controller as a property. when doing this loading and unloading the tab bar works fine but no viewWillAppear and similar methods are send to the view controllers of the tab bar. I just don't understand why those messages are not fired!?

So I tried to create a tab bar controller directly in the app delegate in the didFinishLaunchingWithOptions methods. This also works on first sight. even the viewDidAppear and similar methods are fired on the view controllers of the tab bar. The problem here is, that I cannot unload/release the tab bar controller when the user presses the logout button. When sending a release message to the tab bar controller, the app simply crashes!?

[window addSubview:_myLoginViewController.view]; // works
[_myTabBarController.view removeFromSuperview]; // works
[_myTabBarController release]; // crash

What am I doing wrong? Any faults in my logic? How to unload a tab bar controller?

Thank you!

[bytor99999]

Well maybe it is as simple as the [_myTabBarController.view removeFromSuperview]; already releases the ViewController too, so the retain count went from 1 to 0, then you try to release from 0, when it is already completely released.

Mark

[SteveMobs]

Thanks for this suggestion. I tried:

NSLog(@"tabBar retainCount before removeFromSuperview = %d", [self.tabBarController retainCount]);
[self.tabBarController.view removeFromSuperview];
NSLog(@"tabBar retainCount after removeFromSuperview  = %d", [self.tabBarController retainCount]);
[self.tabBarController release];

which results in the output:

tabBar retainCount before removeFromSuperview = 1
tabBar retainCount after removeFromSuperview = 1
Program received signal: “EXC_BAD_ACCESS”.

:-(

I could live with having the tab bar controller in the background all the time but I would like to remove the view controllers at least so that quite some objects get deallocated.

self.tabBarController.viewController = nil;

This also results in a EXC_BAD_ACCESS... I thought it is possible to remove the view controllers at runtime!?

I was searching the web for any example in which a UITabBarController is removed from the super view. Even the Apple UICatalogue example seems to avoid the tab bar controller.