I would like to be able to handle orientation changes in my current iPhone application. The problem is that I don't want the view of my controller to rotate or resize. When the device orientation changes, I just want one UI element to rotate 90 degrees on the screen.
Apple's camera application is a perfect example of this - when the device orientation changes, all of the buttons rotate, but the view itself does not rotate.
I suppose that I could just resize the view, move all of my elements around, and then animate the buttons, but I feel like there must be an easier way to do it.
Thanks in advance.
1) You can create 2 view hierarchies and change which is on screen in willRotateToInterfaceOrientation:
see this question
2) Or you can handle all rotations yourself
see this question
You can use
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
if(interfaceOrientation==UIInterfaceOrientationPortrait || interfaceOrientation==UIInterfaceOrientationPortraitUpsideDown)
{
//Change frames as per orientations
}
else
{
//Change frames as per orientations
}
return NO;
}
and based on the orientation manually set the frames of the UI elements you want to change.
you can access all the orientation from Constants section of this doc.
EDIT:
You can use NSNotification for the issue.
UIApplicationDidChangeStatusBarOrientationNotification
Posted when the orientation of the application's user interface
changes.
The userInfo dictionary contains an NSNumber object that encapsulates
a UIInterfaceOrientation value (see UIInterfaceOrientation). Use
UIApplicationStatusBarOrientationUserInfoKey to access this value
Availability
Available in iOS 2.0 and later.
Declared In UIApplication.h
I've been searching through lots of posts trying to find a way to change the orientation of the view manually. However I can't seem to find a definitive answer that's not outdated. Please can someone suggest the best way to switch the orientation based on when a user presses a button?
I.e. I need some help filling in the gap...
- (IBAction)buttonPressed:(id)sender
{
// Switch the orientation to ...
}
The Apple guideline doesn't allow that. There's some hack to do that but it's not a good idea to use it.
Your app will run in a real device and there isn't any piece of code that can physically turn the phone. Device orientation is constraint by real world constraint, you can't force your user to turn his phone.
[UIApplication sharedApplication].statusBarOrientation = UIInterfaceOrientationLandscapeLeft
Change the orientation to Landscape or Portrait.
You might have to also apply a transformation to complete the change:
self.view.transform = CGAffineTransformRotate(self.view.transform, -(M_PI / 2.0));
How can I retrieve a rotation specific applicationFrame/screen bounds? The "applicationFrame" method always returns 768x1024 on the iPad, no matter whether the device is in landscape or portrait mode. I am looking for a method that would return me 1024x768 if the device is in landscape and 768x1024 if its in portrait.
I am sure there is something like this out there but I just can't find it. In case it really doesn't exist, how do make your iPad apps landscape and portrait compatible?
[UIDevice currentDevice].orientation
Will return one of
typedef enum {
UIDeviceOrientationUnknown,
UIDeviceOrientationPortrait,
UIDeviceOrientationPortraitUpsideDown,
UIDeviceOrientationLandscapeLeft,
UIDeviceOrientationLandscapeRight,
UIDeviceOrientationFaceUp,
UIDeviceOrientationFaceDown
} UIDeviceOrientation;
From there, you can deduce what the current frame should be.
Turns out applicationFrame works fine, but only if the autorotation is properly implemented! In my case the controller of the view that was added as subview to the UIWindow was released too early, which seems to cause applicationFrame to break along with the autorotation mechanism. I think this is because the responder chain can no longer function properly, yet I did not verify this.
I don't need to specify the orientation in this case, I just need to detect it, but I'm having trouble. I have conditional code that should only work in portrait, and if the device is in landscape I need to do something else. Since the deviceOrientation is not necessarily the same as the interfaceOrientation, I can't come up with a way to test for portrait mode.
Most tutorials I find on Google are ways to force landscape or do some sort of rotation. The only thing I want to do is just determine what the orientation is. Here is my code, which is not working:
-(void)viewDidLoad {
[super viewDidLoad];
//currentOrientation is declared as UIInterfaceOrientation currentOrientation
currentOrientation = [[UIApplication sharedApplication] statusBarOrientation];
NSLog(#"%#",currentOrientation); // == NULL
}
I need to determine the value of the interfaceOrientation and program conditionally. Thanks for your help!
Are you aware of the interfaceOrientation property of the UIViewController class?
- (void) viewDidLoad {
[super viewDidLoad];
BOOL isPortrait = UIDeviceOrientationIsPortrait(self.interfaceOrientation);
// now do whatever you need
}
Or are you after [[UIDevice currentDevice] orientation]?
Especially at launch I have found the following to be always accurate for the UI, regardless of what the UIDevice says the orientation is.
[UIApplication sharedApplication].statusBarOrientation
self.interfaceOrientation is unreliable in certain situations. For example, re-arranging tabs in a tabbar application returns incorrect value.
However [UIApplication sharedApplication].statusBarOrientation is always reliable. You saved me a lot of time slycrel. Thank you.
UIInterfaceOrientation orientation = [UIApplication sharedApplication].statusBarOrientation;
if ((orientation == UIInterfaceOrientationLandscapeLeft)
|| (orientation == UIInterfaceOrientationLandscapeRight) )
{
//Landscape
}
else
{
//Portrait
}
I know it is a very old post. How ever I would like to add a point to say it is better to check status bar orientation is better. When ever you call self.interfaceorientation it is calling shouldRotateToOrientation every time. If you have written some code in that method it will be executed. So be cautious!.
UIDeviceOrientation deviceOrientation = [UIDevice currentDevice].orientation;
UIInterfaceOrientation statusBarOrientation = [UIApplication sharedApplication].statusBarOrientation;
if(deviceOrientation == UIDeviceOrientationFaceUp || deviceOrientation == UIDeviceOrientationFaceDown){
if(debug){
NSLog(#"Nothing to change because it is gone to Flat");
}
return;
}
if(deviceOrientation !=statusBarOrientation){
if(debug){
NSLog(#"\nApple has a bug?:\n UIDeviceOrientation : %d, UIInterfaceOrientation: %d",deviceOrientation, statusBarOrientation );
}
}
You won't believe me until you will see at the console the second output!
Some situations - and they exists! - is displayed the last NSLog content!
Than you have to do some workarounds to go on that way, where iOS has no bug, good luck for everyone!
Ah that ... forum moderator maybe will delete this post too, because this doesn't meant to be and answer in his opinion!
I hope it helps for somebody once, it happens on iphone too...(there I got)
Mix it up a little:
BOOL isLandscape = self.view.frame.size.width > self.view.frame.size.height;
(edit) Obviously the previous answers are the correct way to do this and this solution would fail in a situation where view controllers are not full-screen.
-(void)willRotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration{</br>
if (UIDeviceOrientationIsLandscape(toInterfaceOrientation)) {</br>
some instructions;
} else {
some instructions;
}
}
This is a snippet from one of my programs.
You could of course use the if statement in your ViewDidLoad notification as well.
I already voted up the answer by #slycrel, but I would like to take the time to write this, and point some things out that seems to be lost in this old question, and lots of other questions on the subject.
It's true that Apple does not really want us to update most of our UI based on orientation changes, but it is still totally possible and sometimes necessary on a case by case scenario, and it will be that way until Apple improves their new(ish) APIs (e.g. viewWillTransitionToFrame: would be way more useful than viewWillTransitionToSize:. Just sayin')
Why I voted up the answer by #slycrel is related to what you need to keep in mind as the logical difference between UIDeviceOrientation and UIInterfaceOrientation.
Tthe status bar is what denotes an application's currently known UIInterfaceOrientation. All this stuff about FaceUp, FaceDown is only related to a device's orientation, not necessarily your application's. An application does not support device orientations anyway. Really, UIDeviceOrientation can be ignored completely if all you have to do is make sure you layout and animate things appropriately in your interface, which is 99% of an application developer's use cases. This is currently achieved with the status bar's UIInterfaceOrientation from #slycrel's answer:
[UIApplication sharedApplication].statusBarOrientation
It should be noted, the readwrite version of this property is deprecated, the readonly version is not.
Take this example:
I have an application that supports ALL interfaces orientations, and a root view controller that supports them as well.
Now, I am presenting a UIViewController that will result in the status bar orientation to become landscape.
Which landscape orientation (left or right) it goes to is based on what is returned by preferredInterfaceOrientationForPresentation for that view controller, what the current device orientation is, and what interface orientations the view controller supports (see next point).
The status bar will go to landscape, regardless of what the current device orientation is, because this view controller only supports landscape based on what is returned by supportedInterfaceOrientations. Lets say we support both landscape left and right with UIInterfaceOrientationMaskLandscape.
I also want to conditionally animate this view controller into position with a rotation transform. This will only be necessary when going from portrait or portrait upside down, to landscape left or landscape right. Otherwise it will be a more simple presentation animation without rotation.
Then, after some time and device use, I dismiss that view controller.
Now I want to conditionally animate this view controller off the screen with another rotation transform. This will only be necessary when going from landscape left or landscape right, to portrait or portrait upside down. Otherwise it will be a more simple dismissal animation without rotation.
At this point, the status bar's orientation will become whatever the system decides is appropriate for the combination of your root view controller's preferred interface orientation and supported interface orientations, as well as the device's current UIDeviceOrientation.
Since the view controller we are going to supports ALL interface orientations, if your device's orientation is FaceUp or FaceDown, you can not reliably guess the next UIInterfaceOrientation based on UIDeviceOrientation, and you do not have to anyway.
So... status bar orientation to the rescue!
The previous example is possible, because the status bar orientation is not updated when a view controller transition is about to start (the system asks a transition delegate for an animator, etc.). Then it is updated when the transition starts animating (e.g. by the time animationTransition: is called). This way you should have a good comparison just using the initial and current values of the status bar's UIInterfaceOrientation.
Even without using view controller transitions, it should still be safe to update views based on the status bar orientation.
Keep in mind, if you are manually updating the status bar, and if you are not using "View controller-based status bar appearance" in your Info.plist, then your application's logic must be aware when the status bar will and did change orientation. You will probably be looking for a couple NSNotification names for these cases, which are:
UIApplicationWillChangeStatusBarOrientationNotification
UIApplicationDidChangeStatusBarOrientationNotification
As well as these UIApplicationDelegate methods:
- (void)application:(UIApplication *)application willChangeStatusBarOrientation:(UIInterfaceOrientation)newStatusBarOrientation duration:(NSTimeInterval)duration;
- (void)application:(UIApplication *)application didChangeStatusBarOrientation:(UIInterfaceOrientation)oldStatusBarOrientation;
- (UIInterfaceOrientationMask)supportedInterfaceOrientationsForWindow:(nullable UIWindow *)window
And this other helpful UIApplication property:
#property(nonatomic,readonly) NSTimeInterval statusBarOrientationAnimationDuration;
As of iOS8, APIs have been deprecated or return unhelpful results such as .FaceUp .FaceDown
This is because Apple does NOT want you to update your UI using orientation, but rather by using size classes, constraints, and proportion (using n% of superview).
Indeed, orientation dependent code might fail to provide good results across the whole range of device and use case (especially multitasking)
The iphone app I am developing in landscape mode is seriously chugging. I put it in portrait for comparison and it appears to run much smoother in that orientation. I am not doing what I'd think is process intensive: a map view, some buttons, some labels, and some quartz drawing, yet some basic quartz animation seriously slows down really badly.
Does anyone know if landscape mode is just terribly handicapped compared to portrait, and/or if so, if there are better ways to create a landscape app? I simply use a root rotated view transformed 90 degrees and attach all my sub views to it.
Thanks.
There should be no real difference between landscape and portrait orientations when it comes to rendering performance. Are you using a transform to rotate your main view 90 degrees? As of iPhone OS 2.1, I believe, you no longer need to manually apply a transform to your main view to get it to start in landscape. All I had to do to force landscape orientation was to place this delegate method within my application delegate:
- (void)application:(UIApplication *)application willChangeStatusBarOrientation:(UIInterfaceOrientation)newStatusBarOrientation duration:(NSTimeInterval)duration;
{
// This prevents the view from autorotating to portrait in the simulator
if ((newStatusBarOrientation == UIInterfaceOrientationPortrait) || (newStatusBarOrientation == UIInterfaceOrientationPortraitUpsideDown))
[application setStatusBarOrientation:UIInterfaceOrientationLandscapeRight animated:NO];
}
and the following in my root view controller:
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
return ( (interfaceOrientation == UIInterfaceOrientationLandscapeLeft) || (interfaceOrientation == UIInterfaceOrientationLandscapeRight));
}
Maybe you do some divisions which result in non-integer pixel positions ( like 0.76 ). I had some issues with performance when i had non-integer pixel positions. (Though i am not completely sure these were connected. But maybe it helps you)
Thank you for all your suggestions and help, everyone. I tried Brad's suggestion of setting the view controller autorotate settings and it worked extremely well. I think that was a huge contributing factor to the slowdown.