Easiest way to support multiple orientations? How do I load a custom NIB when the application is in Landscape?

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I have an application in which I would like to support multiple orientations. I have two .xib files that I want to use, myViewController.xib and myViewControllerLandscape.xib. myViewController.xib exists in project/Resources and myViewControllerLandscape.xib exists in the root project directory.

What I want to do is use a separate NIB (myViewControllerLandscape.xib) for my rotations. I try detecting rotation in viewDidLoad like this:

if((self.interfaceOrientation == UIInterfaceOrientationLandscapeLeft) || (self.interfaceOrientation == UIInterfaceOrientationLandscapeRight))
 {
  NSLog(@"Landscape detected!");
  [self initWithNibName:@"myViewControllerLandscape" bundle:nil];

 }

But I can see in gdb that this isn't executed when the app is started with the device in landscape. The NSLog message doesn't fire. Why is this? What have I done wrong?

Also, if I explicitly put the initWithNibName function call in the viewDidLoad method, that nib is not loaded, and it continues with the myViewController.xib file. What's wrong with my call? Should I specify a bundle?

Thanks!

Time answered 22/3, 2010 at 23:43 Comment(0)

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You have to load one view, then check orientation and load another if needed. You check orientation in shouldAutorotateToInterfaceOrientation: returning yes if you want to rotate.

I use a navigation controller to manage the transition. If I have the portrait view up and the device rotates, I push the landscape view and then pop the landscape view when it return to portrait.

Edit:

I return YES for all orientations in shouldAutorotateToInterfaceOrientation: but will this be called when the app launches? Do you push your view inside of this function?

The orientation constants are not globals you query but rather part of the messages sent the controller by the system. As such, you cannot easily detect orientation before a view controller loads. Instead, you hardwire the app to start in a particular orientation (usually portrait) and then immediately rotate. (See mobile Safari. It always starts in portrait and then rotates to landscape.)

These are the two methods I used to swap out my portrait and landscape views.

All three view controllers have this method:

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {
    // Return YES for supported orientations
    return (interfaceOrientation != UIInterfaceOrientationPortraitUpsideDown);
}

The portrait has this:

- (void)willRotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration {

    if (toInterfaceOrientation==UIInterfaceOrientationLandscapeRight) {
        [self.nav pushViewController:rightLVC animated:NO];
    }
    if (toInterfaceOrientation==UIInterfaceOrientationLandscapeLeft) {
        [self.nav pushViewController:leftLVC animated:NO];
    }
}

Each landscape controller has this:

- (void)willRotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration {

    if (toInterfaceOrientation==UIInterfaceOrientationPortrait) {
        [self.nav popViewControllerAnimated:NO];
    }

The app starts in portrait. If the orientation of the device is landscape, it pushes the appropriate landscapes. When the device rotates back to portrait, it pops the landscape. To the user it looks like the same view reorganizing itself for a different orientation.

Blown answered 23/3, 2010 at 0:27 Comment(10)

I return YES for all orientations in shouldAutorotateToInterfaceOrientation: but will this be called when the app launches? Do you push your view inside of this function? – Time 23/3, 2010 at 2:27

Do you have 3 view controllers? If so, how do they talk with each other (how can they all access the nav parameter)? I've tried your code but avoided having 3 controllers. I've tried the following in willRotateTo...: if((toInterfaceOrientation == UIInterfaceOrientationLandscapeLeft) || (toInterfaceOrientation == UIInterfaceOrientationLandscapeRight)) { myViewController *newVC = [[myViewController alloc] initWithNibName:@"myViewControllerLandscape" bundle:nil]; [self.nav pushViewController:newVC animated:NO]; } but no dice. Should I create a whole separate landscape view controller? – Time 23/3, 2010 at 20:0

I know this question is old, but I have an additional question/suggestion: when I want to load a new view controller inside of a tabbar when the orientation changes, that code will not work because a tabbar's navigation controller returns nil. Instead, I loaded a new view and set a view programmatically instead of swapping out view controllers. I'm not sure if this is the right way to do this, but it seems to work. Hope it helps someone... – Bullhead 30/3, 2011 at 23:16

If you want to use this with a tabbar, you would make a navigation controller the top controller in a particular tabview instead of the entire tabbar controller. Then it would work as above. – Blown 31/3, 2011 at 14:45

The only problem I see with this is that you said that if the device is in landscape while the next vc is pushed, you will push the appropriate landscape controller. If that is so, and the orientation changes while that pushed landscape vc is active, the willRotateToInterfaceOrientation: duration: implementation will pop not to the portrait version, but to the previous view controller. Am I missing something? – Dumbbell 21/5, 2011 at 23:5

The navigation controller responds instantly to changes in orientation. Whenever you rotate from one landscape to another, you: pop the current landscape, push the portrait, pop the portrait and then push the other landscape. You can't move from one landscape vc to another without first transitioning through the portrait vc. Each landscape vc only knows how to pop itself back to the portrait vc. In turn, the portrait vc always loads the needed landscape vc for the next rotation. – Blown 22/5, 2011 at 14:14

This answer ALMOST works - unfortunately, because it inserts an extra item into the Nav stack, it breaks the UINavigationBar (you get an extra entry). I had to add a bunch of logic to intelligently hide the navigationBar when pushing landscape OR popping to landscape, and unhide it when pushing anything else – Mallina 5/3, 2012 at 3:5

This approach will cause you grief if you're using a nav controller to manage your hierarchy of views. You either have to nest nav controllers, or use a single nav controller in which case you run into the problems that Adam is describing. – Spondaic 14/3, 2012 at 1:50

I found an alternative that currently works perfectly (iOS 5) - see answer below. It might not work for you (I've only tried it in one of my apps so far) – Mallina 10/5, 2012 at 12:4

The solution is perfect only when there is view part.But this won't work properly, If I got one registration screen controller in both orientation.If filling up few files & I rotate my device then it won;t load that filled data onto another view which got oriented since either it gets pushed or pop.so, I didn;t find this one as an ideal solution where user need to enter the values.The values gets lost when device gets rotated.Do you got some alternative to achieve this ? – Imitative 15/6, 2012 at 7:25

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I found a much better way that works independent of the nav controller. Right now, I have this working when embedded in a nav controller, and when NOT embedded (although I'm not using the nav controller right now, so there may be some bug I've not seen - e.g. the PUSH transition animation might go funny, or something)

Two NIBs, using Apple's naming convention. I suspect that in iOS 6 or 7, Apple might add this as a "feature". I'm using it in my apps and it works perfectly:

triggers on WILL rotate, not SHOULD rotate (waits until the rotate anim is about to start)
uses the Apple naming convention for landscape/portrait files (Default.png is Default-landscape.png if you want Apple to auto-load a landscape version)
reloads the new NIB
which resets the self.view - this will AUTOMATICALLY update the display
and then it calls viewDidLoad (Apple will NOT call this for you, if you manually reload a NIB)

-(void)willRotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration
{
    if( UIInterfaceOrientationIsLandscape(toInterfaceOrientation) )
    {
        [[NSBundle mainBundle] loadNibNamed: [NSString stringWithFormat:@"%@-landscape", NSStringFromClass([self class])]
                                      owner: self
                                    options: nil];
        [self viewDidLoad];
    }
    else
    {
        [[NSBundle mainBundle] loadNibNamed: [NSString stringWithFormat:@"%@", NSStringFromClass([self class])]
                                      owner: self
                                    options: nil];
        [self viewDidLoad];
    }
}

Mallina answered 10/5, 2012 at 12:3 Comment(11)

This is how I have always done orientation changes, having additional view controllers is silly, unnecessary and wasteful of resources.. not to mention what others above pointed out that it leaves a view controller/view in the stack etc. – Annals 9/6, 2012 at 5:37

You just only need to keep im mind to carry about avoiding allocations in your viewDidLoad, because in this case it coz memory leaks. – Twila 28/6, 2012 at 12:27

If you have memory leaks in your viewDidLoad, then ... you already had memory leaks in your viewDidLoad. Perhaps you could insert a "[self viewDidUnload]" call first, if you need to balance your leaks? – Mallina 28/6, 2012 at 12:56

I've found this to be a much better solution than the accepted answer. Different controllers / "invisible" navigation stack items always struck me as hacky. The only caveat is that the nibName property doesn't update when you load a new one. Thanks. – Donyadoodad 22/7, 2012 at 15:51

Thank You Adam ! I got stuck with a storyboard app needing older code that directly loaded its nibs. Nibs not in the storyboard that is. Was at a loss how to get the rotations to happen on the non-storyboard nibs. Your suggestion, as user282171 said, really clarified the old way ( which is clearly still valid ) and solved the issues. The problem is that storyboarding embeds its nib files and you have to get at them by code [vc.storyboard instatiateViewControllerWithIdentifier ... ]; but if the view-nib you need is standalone ...then [insert Adam's solution here] ;)) – Solo 17/3, 2013 at 23:51

Hi @Mallina I did what you have said in this answer it loads the landscape view, but the view is rotated by an angle to 90 degrees.. Though i built the view in IB in landscape orientation .. it is not appearing like that .. what have i done wrong .. how should the view be created in Interface builder. – Puttergill 20/3, 2013 at 10:18

@Sakti sounds like you have a bug in your code somewhere else. Without this code, just loading the NIB normally, is the orientation correct? You should open a new stackoverflow question if not. – Mallina 20/3, 2013 at 13:28

@adam i solved it .. i was trying this for modally presented view controller .. which gave a strange behaviour. i added the view controller to navigation controller and presented it which made it work as intended .. ;) – Puttergill 20/3, 2013 at 18:37

Hi @Adam, I'm having the same issue that Sakti had. I used amergin initWithNibNamed to get the first launch to work (my simulator is coming up landscape now) and my landscape is correct. I go to portrait, and it is correct also, but when I go back to landscape I see that the landscape xib loaded, but it itself is rotated 90 degrees. Does this trick no longer work in iOS6. If you want I'll make a new question. – Pentamerous 2/7, 2013 at 20:5

I did post a new question: #17435897 – Pentamerous 2/7, 2013 at 20:46

I've tried this solution and found the following issues: 1. On initial load of the VC, you have to select the right nib. 2. On return to this view, you have to check if you're showing the right orientation somehow. I've found this to be difficult to get right. – Isolationism 5/10, 2013 at 19:0

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