Supporting two orientations with separate view controllers in iOS

Question

I'm in a real mess right now . I used apples sample code which does this :

1. Create a portrait view controller and a landscape view controller
2. Potrait event controller then registers for device orientation changed notifications
3. When device is rotated it presents a modal view controller for the landscape view or dismisses the landscape view if it is rotated back to portrait .
   Everythings working as it should except for a little problem ....

Now to my problem . I used this to launch a rotatable view controller from a table view . It can be rotated and works fine . But if I initially launch it in landscape mode it will still launch as portrait . If i want landscape i have to afterwards AGAIN rotate it to landscape .I tried very hard to fix for this but failed . You can download and run the sample code from Apple Developer Site Here . Can anyone fix this code so that if launched in landscape mode it presents the modal view for the landscape view ? Otherwise I'll have to rewrite everything to use a single view controller . These are the relevant portions of apples code :

- (void)viewDidLoad
{
self.view.backgroundColor = [UIColor colorWithRed:197.0/255.0 green:204.0/255.0 blue:211.0/255.0 alpha:1.0];

LandscapeViewController *viewController = [[LandscapeViewController alloc]
                                                initWithNibName:@"LandscapeView" bundle:nil];
self.landscapeViewController = viewController;
[viewController release];

[[UIDevice currentDevice] beginGeneratingDeviceOrientationNotifications];
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(orientationChanged:)
                                                name:UIDeviceOrientationDidChangeNotification object:nil];

}

- (void)orientationChanged:(NSNotification *)notification
{
// We must add a delay here, otherwise we'll swap in the new view
// too quickly and we'll get an animation glitch
[self performSelector:@selector(updateLandscapeView) withObject:nil afterDelay:0];
}

- (void)updateLandscapeView
{
UIDeviceOrientation deviceOrientation = [UIDevice currentDevice].orientation;
if (UIDeviceOrientationIsLandscape(deviceOrientation) && !isShowingLandscapeView)
{
    [self presentModalViewController:self.landscapeViewController animated:YES];
    isShowingLandscapeView = YES;
}
else if (deviceOrientation == UIDeviceOrientationPortrait && isShowingLandscapeView)
{
    [self dismissModalViewControllerAnimated:YES];
    isShowingLandscapeView = NO;
}    
}

// override to allow orientations other than the default portrait orientation
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{return (interfaceOrientation == UIInterfaceOrientationPortrait); // support only portrait}

Answer 1

I know this is probably no longer relevant to you, but I just came across the same glitch and here's my solution.

From the way you have your code set out (including how Apple sets it out)

- (void)updateLandscapeView

is only called once a Notification is sent out telling the ViewController of an orientation change: the issue here is, that this is the method responsible for checking the orientation it self. (i.e. Starting the application this method is not called and therefore it doesn't check whether the device is in any other orientation)

The solution is quite simple: Force cal themethod at launch, i.e. in viewDidLoad . . .

[self  updateLandscapeView]

This will force call the method and check the interfaces orientation, after the first time, the method will be called again when ever it receives a notification for a changed Orientation

Hope this helps someone Out There

Answer 2

It seems that the device assumes portrait unless you specify landscape only in settings. Your only option would be in your portrait view in the loadview method to detect the orientation and to swap views during launch.

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
        {
           if(interfaceOrientation == UIInterfaceOrientationPortrait || interfaceOrientation == UIInterfaceOrientationPortraitUpsideDown ) {
        //Load vertical interface
           }
    else
    {
    //load landscape
    }
        }