popToRootViewController crashes when called by UITabBarControllerDelegate - iphone

Question

I have a UITabBarController with 4 UINavigationControllers. I have implemented the didSelectViewController Delegate Method as follows:
-(void)tabBarController:(UITabBarController *)tabBarController didSelectViewController:(UIViewController *)viewController {
if ([viewController isKindOfClass:[UINavigationController class]]) {
[(UINavigationController *)viewController popToRootViewControllerAnimated:NO];
}
}
It crashes when a NavigationController is at a 2nd Level after didSelectRowAtIndexPath pushes a new viewController onto the stack.
-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
// Navigation logic may go here. Create and push another view controller.
RootViewController *detailViewController = [[RootViewController alloc] initWithNibName:#"RootViewController" bundle:nil];
// ...
detailViewController.title = [self.temp objectAtIndex:indexPath.row];
detailViewController.sort = self.title;
// Pass the selected object to the new view controller.
[self.navigationController pushViewController:detailViewController animated:YES];
[detailViewController release];
}
Of course the debugger with NSZombies enabled doesn't give any feedback.
However, if I add retain to detailViewController alloc;
RootViewController *detailViewController = [[[RootViewController alloc] initWithNibName:#"RootViewController" bundle:nil] retain];
It works, but leaks memory.
Any ideas what is wrong, how to fix, what is happening?

Answer 1

I have the similar scenario and i came up with following solution.
In my application i have login screen at launch and then I have UITabbarController with 4 UINavigationControllers.
I have created property of UINavigationController in AppDelegate.h file.
#property (strong, nonatomic) UINavigationController *navigationController;
Then
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions (NSDictionary *)launchOptions
{
//Override point for customization after application launch.
LoginViewController *loginViewController = [[LoginViewController alloc] initWithNibName:#"LoginViewController" bundle:nil];
self.navigationController = [[UINavigationController alloc] initWithRootViewController:loginViewController];
self.window.rootViewController = self.navigationController;
[self.window makeKeyAndVisible];
return YES;
}
Now when you need to pop to RootViewController then use following code
#import "AppDelegate.h"
[((AppDelegate *)[[UIApplication sharedApplication] delegate]).navigationController popToRootViewControllerAnimated:YES];
Hope this solves your problem.