Presenting a specific view controller from AppDelegate

Question

I am trying to present a view controller (a passcode request type view) every time my app becomes active. Once the correct passcode is entered, it should pop off the stack.

Answer 1

I suggest you use applicationWillEnterForeground:, not applicationDidBecomeActive:, because it works better with multitasking gestures. For example, you don't want to put up the lock screen if the user double-clicks the home button to display the task bar, and then dismisses the task bar without changing apps.

Presumably your AppDelegate has a window property, and you know that your window's root view controller is a UINavigationController.

- (void)applicationWillEnterForeground:(UIApplication *)application {
    PasscodeViewController *pvc = [[PasscodeViewController alloc] init];
    [(UINavigationController *)self.window.rootViewController pushViewController:pvc animated:NO];
    // [pvc release]; if not using ARC
}