How do I present a modal view at application startup?

Question

I have the following code in application didFinishLaunchingWithOptions where I want to present a modal view controller for user login.

LoginViewController_iPhone *loginViewController=[[LoginViewController_iPhone alloc]initWithNibName:@"LoginViewController_iPhone" bundle:nil];
UINavigationController *loginNavigationController=[[UINavigationController alloc]initWithRootViewController:loginViewController];
loginNavigationController.modalPresentationStyle=UIModalPresentationFullScreen;
[self.window.rootViewController presentModalViewController:loginNavigationController animated:NO];

[loginViewController release];
[loginNavigationController release];

However, all I get is a blank white screen. If I substitute the following

self.window.rootViewController=loginNavigationController;

the login screen displays correctly. There is no other view controller assigned to the rootViewController property as the app is just starting. Do I need another view controller assigned to get this to work?

score 3 · Accepted Answer · answered Jul 19 '11 at 17:03

3

Yes. you need to assign something to the window's rootViewController property in order to call its method presentModalViewController.

answered Jul 19 '11 at 17:03

Jesse Naugher

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Works. Thanks. That was what I suspected. – ChrisP Jul 19 '11 at 17:08
just a general thing, you were trying to call a method on an object that was nil. – Jesse Naugher Jul 19 '11 at 17:09

score 0 · Answer 2 · answered Jul 19 '11 at 17:05

0

UINavigationController *navController = [[UINavigationController alloc] initWithRootViewController:LoginViewController];

navController.modalTransitionStyle = UIModalTransitionStyleFlipHorizontal;
[self presentModalViewController:navController animated:NO];

You can set this up in the viewDidLoad of the view that would load up first as soon as the app starts. So, as soon as login is successful, you can pop it off, and you will have the loaded view ready.

answered Jul 19 '11 at 17:05

Legolas

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While this approach would work I chose the first answer as a callback via a delegate to the AppDelegate gives me more control after login. – ChrisP Jul 19 '11 at 17:35

How do I present a modal view at application startup?

2 Answers2

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