Consider a UIViewController that supports different interface orientations based on its state, which can change based on user input.
AFAIK, supportedInterfaceOrientations is only called when the device orientation changes. Is there a way to tell the application that it needs to ask again about the supported interface orientations, even if the device orientation didn't change?
You're correct. Basically you can only respond to an orientation change, not force it.
But there is a trick you can use to fool the application to go through all the orientation callbacks.
You should have a ViewController which you created at the start of your app and set as the window's rootViewController. Remove that ViewController's view from its superview (which is the window) and immediately add it as a subview to the window again. Since the entire visible view hierarchy just changed, the app will go through all orientation callbacks again.
But I wouldn't rely on this too much if I were you, while it is logical for this to happen, you never know when Apple might change this. Now that I think of it, I haven't tested this in iOS 6 yet. It does work on iOS 4 and 5.
Related
I have a systemic portrait-mode storyboard.
However I want to be able to rotate one scene to landscape mode without affecting other storyboard scenes.
Is this possible and how would I implement it?
Override the supportedInterfaceOrientations method in the view controller you want to allow landscape in, to return UIInterfaceOrientationMaskAllButUpsideDown or whichever value is suitable. This property is also configurable from the storyboard.
This will not affect the possible orientations of other view controllers; the app's UI orientation will automatically change back to portrait when you go to another scene.
You might need to uncheck Device Orientation options located in the project's General Settings for this to take effect (I didn't need to, but it seems to be necessary for some people):
My app runs in portrait mode, but i want to show one screen in landscape mode only as it is a chart. What do i add to my uiviewcontroller to force it into landscape mode only?
I'm sorry but this answer will be very short: If you're using the UINavigationController, you can't. The answer #jer gives is therefore incorrect. The Apple documentation states:
All child view controllers in your UITabBarController or UINavigationController do not agree on a common orientation set.
I recently had this question answered on a bounty and my app rejected in the process. Read up on that here: How to constrain autorotation to a single orientation for some views, while allowing all orientations on others?
The only solution you have, is to throw away the UINavigationController and rewrite it with something of your own.
By presenting and dismissing a view controller modally you can force an orientation. Set animations to "NO" and you can do this without the user even realizing it occurred.
You can read more about this Josh's answer on Is there a documented way to set the iPhone orientation?
I consider it a bit of a hack, but I've successfully implemented code using this premise to force any device orientation.
You implement shouldAutorotateToInterfaceOrientation: and have it return only YES for UIInterfaceOrientationIsLandscape(param) where param is the parameter you declared for the method.
This will support landscape left and landscape right, instead of locking you to only one landscape orientation.
My app has 4 tabs. All the view controllers support rotation, and indeed are rotated when I rotate the device. For one of the view controllers, I need to reposition some of the subviews upon rotation. I do this in willRotateToInterfaceOrientation of that view controller, and it works fine.
The problem comes when I switch to a different tab, then rotate the device, then go back to the original tab. It apparently has not received the rotation notification, since willRotateToInterfaceOrientation has not been called. So it seems as though only the "active" view controller gets notified that the device has rotated.
The question: how do you get all the view controllers (controlled by a TabBarController) to rotate?
Unfortunately this is a bug in iOS 3.x. It works fine in iOS 4.x. I've seen apps that manually keep track of orientation changes and then do the rotation manually for inactive viewcontrollers. Sucks.
Looking through the iOS 3.2 docs to make sure this works, there is a viewControllers property in UITabBarController. Try something like this:
for (UIViewController * viewController in tabBarController) {
// Do stuff here with each 'viewController'.
}
I recommend that you do something with the UIViewController's -shouldAutorotateToInterfaceOrientation: method but you may have another way in which you plan on achieving the rotation.
You should also check for the interface orientation in viewWillAppear method of the controller whose subviews frame you are changing.Because when you move to the new tab and rotate the device and now when you tap another tab the viewWillAppear method will we called and there you can change the frames accordingly.
I also faced the same problem which i sorted out using this approach
I'm strugging with getting an iPhone application which requires just about every push or pop in the Nav Controller Stack to change orientation.
Basically the first view is portrait, the second landscape the third portrait again (Yes I know this is less than ideal, but that's the design and I've got to implement it).
I've been through various advice on here....
How do I detect a rotation on the iPhone without the device autorotating?
Force portrait orientation on pushing new view to UINavigationViewController
Is there a documented way to set the iPhone orientation?
But without total success.
Setting to link against 3.1.2 my reading of the linked articles above seems to indicate that if my portrait view pushes a view with
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {
// Return YES for supported orientations
return ((interfaceOrientation == UIInterfaceOrientationLandscapeRight) );
}
Then then that view should appear rotated to landscape. What happens is it appears in its "broken" portrait form, then rotates correctly as the device is turned.
If I pop the controller back to my portrait view (which has an appropriate shouldAutoRotate...) then that remains in broken landscape view until the device is returned to portrait orientation.
I've also tried removing all the shouldautorotate messages, and instead forcing rotation by transforming the view. This kind of works, and I've figured out that by moving the status bar (which is actually hidden in my application) [UIApplication sharedApplication].statusBarOrientation = UIInterfaceOrientationLandscapeRight; the keyboard will appear with the correct orientation when desired.
The problem with this approach is that the status bar transform is weird and ugly when you don't have a status bar - a shadow looms over the page with each change.
So. What am I missing.
1) Am I wrong in thinking that in 3.1.2 (or possibly earlier) shouldAutorotateToInterfaceOrientation should provide the desired orientation simply by pushing controllers ?
2) Is there another way of getting keyboards to appear in the correct orientation.
3) Are the undocumented API calls the way to go (please no!)
You shouldn't use [UIViewController shouldAutorotateToInterfaceOrientation:] to trigger an orientation change; it's only there to let the system know if automatic rotations are allowed. You should still update it to specify the orientation that's allowed though.
If you want to change the orientation when a particular view is showing, you should call [UIApplication setStatusBarOrientation:animated:] inside your [UIViewController viewWillAppear:] override method for each of the view controllers that force a particular orientation. That will cause a change when a view is being pushed onto the stack and when it's being popped off it. Make sure you call super in your override method.
This is also the right place to change how the status bar is displayed, if that's something you're doing.
I did some experiments on autorotation.
The situation: I have a TabBar 4(tabs), three should be portrait only. The last one is a UINavigationController, which by itself should not autorotate any of the stacked controllers. It is basically a browsing application, as I show file and folders everything should be portrait. Some times, a special UIViewController is pushed, and I would like only this one to autorotate (it is always the last on the stack). In this last view, the tabbar is hidden.
How I achieved the goal: I subclassed the UITabBarController, to override the standard shouldAutorotate method behaviour:
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {
if([self.selectedViewController isKindOfClass:[UINavigationController class]])
return [[(UINavigationController*)self.selectedViewController visibleViewController] shouldAutorotateToInterfaceOrientation:interfaceOrientation];
else
return [self.selectedViewController shouldAutorotateToInterfaceOrientation:interfaceOrientation];
This way, the answer of shouldAutorotate is forwarded to the controlled tabs, and in particular for the UINavigationController, it is again delegated to the visible UIViewController. Basically this works, as I have all the UIViewControllers answering NO, except for the particular one I described above: correctly, when rotating the Simulator, only when the special UIViewController is visible, the interface rotates to landscape, whici is perfect. The Tabbar here is hidden, so user don't get that also that one is rotated (which would be unconsistent in my design: basically whenever the tabbar is visible, which means everywhere except in this special view, the application is portrait only).
The problem is that I would like that, even if the device is still in landscape mode and user pops the special ViewController, the interface should behave consistently and return to portrait mode. Instead, when I pop, the interface stays in landscape (it's not designed in that way so it's a mess, of course) even when showing a UIViewController that would answer NO to shouldAutorotate... this is because (I think) the method is called only when rotation occurs, so until the rotation actually occurs again, the interface is rotated to landscape anyway.
How do avoid this? My first solution would be somehow to intercept the popping of the last view, and rotate manually the view before popping... but I'm not sure, I hope there is some more robust method to handle!!
I use the simulator with 3.0, dunno if this makes a difference.
I know that this is not a solution to your problem, but I think you should really avoid this kind of user interface when portrait-only portrait+landscape or landscape-only pages mixed on the same UINavigationController. Unfortunately the rotation management is extremely buggy and the bugs vary on different firmware versions.
I managed to quite the same thing in one of my projects, but had to remove it later due to firmware bugs: for example if you pressed the "back" button in landscape mode and went back to a portrait-only view, it often occured that the status bar and/or the navigation bar remained in landscape mode and the layout was completely broken. As far as I know this bug is not yet fixed although it was already present in firmware 2.x.
If you still want to do this I suggest the following things:
Make sure that all overridden UIViewController methods (init, viewWillAppear, etc) calls its [super methodName]. If not, auto-rotation is silently buggy. This was mentioned in the "Getting Ready for iPhone OS 3.0 Technical Note" (https://developer.apple.com/iphone/checklist/), but currently this document is unavailable :(
You may experiment with calling the undocumented [UIDevice setOrientation:] method when leaving the landscape view. It sometimes needs to be called twice, once with the current orientation and once with the desired orientation :) You may also need to call [UIDevice setStatusBarOrientation:] if the status bar remains in landscape mode. But note that Apple is likely to reject your application if you use these methods (they introduced an automatic tool some time ago which detects the presence of undocumented symbols in your application).
I had the same problem as you, and I solved this way:
I subclassed the UITabBarController, and added the following code:
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
if (self.selectedViewController)
return [self.selectedViewController shouldAutorotateToInterfaceOrientation:interfaceOrientation];
else
return (interfaceOrientation == UIDeviceOrientationPortrait);
}
This way, every child view controller could control its own orientation.
The problem is that you are rotating your UITabBarController (with the child view controller on top of it) rather than just the child view controller. You should be able to implement shouldAutorotateToInterfaceOrientation: only in your child view controller and have it work properly. It would also simplify your code.
I have never had this issue, but I've also never implemented shouldAutorotateToInterfaceOrientation: in a "container" view controller like a UITabBarController or UINavigationController.
The problem with your implementation is that you use the visibleViewController member of UINavigationController. You should use topViewController instead and everything will work as expected.