Question

Right now I have an app where the first screen the users see when they open the app is the login view.

But I only want the user to see that view if it’s the first time they try to login.

Thus I want one view to appear if a certain nsuserdefault field is empty, and the Login View to appear if it isn’t.

How would I go about this?

I tried to insert an if clause in the loginview.m’s viewdidload, but apparently it’s not possible to switch to another view automatically from the viewdidload?

Answer 1

You should implement this in the App’s delegate. This should be done in method:

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions

Check there for values saved in user defaults and fire appropriate controllers.

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    self.window = [[[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]] autorelease];

    // Check user defaults here

    BOOL shouldShowLogin = [[NSUserDefaults standardUserDefaults] boolForKey:@"ShowLogin"];

    MasterViewController *masterViewController = [[[MasterViewController alloc] initWithNibName:@"MasterViewController" bundle:nil] autorelease];

    self.navigationController = [[[UINavigationController alloc] initWithRootViewController:masterViewController] autorelease];


    if (shouldShowLogin) {
        LoginViewController *loginViewController = [[[LoginViewController alloc] initWithNibName:@"LoginViewController" bundle:nil] autorelease];

        [self.navigationController pushViewController:loginViewController animated:NO];
    }

    self.window.rootViewController = self.navigationController;
    [self.window makeKeyAndVisible];
    return YES; }

Above example should show you the idea. It uses navigation controller but the same can be done without navigation controller – by presenting the login controller modally.