如何以编程方式设置设备（UI）方向？

Question

Would like everything on the screen (UI) to be able to rotate from landscape left to right or vica versa.

How do I go about doing this? Is this private?

I know that

-(BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {}

lets you say which orientations the UI can be, but is there a way to force only one at a time?

Cheers

Answer 1

In iOS [[UIDevice currentDevice] setDeviceOrientation:UIDeviceOrientationSomeOrientation] method is absent. But we can rotate a view with status bar, for this:

- (void)showAlbum {
    // check current orientation
    if ([[UIApplication sharedApplication] statusBarOrientation] != UIInterfaceOrientationLandscapeLeft) {
        // no, the orientation is wrong, we must rotate the UI
        self.navigationController.view.userInteractionEnabled = NO;
        [UIView beginAnimations:@"newAlbum" context:NULL];
        [UIView setAnimationDelegate:self];
        // when rotation is done, we can add new views, because UI orientation is OK
        [UIView setAnimationDidStopSelector:@selector(addAlbum)];
        // setup status bar
        [[UIApplication sharedApplication] setStatusBarOrientation:UIInterfaceOrientationLandscapeLeft  animated:NO];
        // rotate main view, in this sample the view of navigation controller is the root view in main window
        [self.navigationController.view setTransform: CGAffineTransformMakeRotation(M_PI / 2)];
        // set size of view
        [self.navigationController.view setFrame:CGRectMake(0, 0, 748, 1024)];
        [UIView commitAnimations];
    } else {
        [self addAlbum];
    }

}

Answer 2

I've had success with this:

 if (self.interfaceOrientation != UIInterfaceOrientationPortrait) {
    // http://stackoverflow.com/questions/181780/is-there-a-documented-way-to-set-the-iphone-orientation
    // http://openradar.appspot.com/radar?id=697
    // [[UIDevice currentDevice] setOrientation:UIInterfaceOrientationPortrait]; // Using the following code to get around apple's static analysis...
    [[UIDevice currentDevice] performSelector:NSSelectorFromString(@"setOrientation:") withObject:(id)UIInterfaceOrientationPortrait];
}

Answer 3

That method is called to determine whether your interface should automatically rotate to a given rotation (ie letting UIKit do the hard work, rather than you doing it manually).

So if you wanted your app to only work in landscape you'd implement the body of that method with:

return UIInterfaceOrientationIsLandscape(interfaceOrientation);

If you wanted your UI to auto rotate to all orientations you could just return YES;

Is that what you were asking?

Answer 4

If you present a modal view controller which implements -shouldAutorotateToInterfaceOrientation: to only support one orientation, the whole interface will automatically be forced into it. I don't think there's a way to programmatically change orientation otherwise.

Answer 5

Also this simple way works:

[[UIApplication sharedApplication] setStatusBarHidden:YES];
[[UIApplication sharedApplication] setStatusBarOrientation:UIInterfaceOrientationLandscapeRight];

and back:

[[UIApplication sharedApplication] setStatusBarHidden:NO];
[[UIApplication sharedApplication] setStatusBarOrientation:UIInterfaceOrientationPortrait];

Answer 6

In Swift to change the orientation to portrait:

UIDevice.currentDevice().setValue(UIInterfaceOrientation.Portrait.rawValue, forKey: "orientation")

See: https://stackoverflow.com/a/24259601

Answer 7

This was addressed by: Guntis Treulands https://stackoverflow.com/a/10146270/894671

//-----------------------------------
// FORCE PORTRAIT CODE
//-----------------------------------
[[UIApplication sharedApplication] setStatusBarOrientation:UIDeviceOrientationPortrait animated:NO];
//present/dismiss viewcontroller in order to activate rotating.
UIViewController *mVC = [[UIViewController alloc] init];
[self presentModalViewController:mVC animated:NO];
[self dismissModalViewControllerAnimated:NO];

Answer 8

if ([[UIDevice currentDevice] respondsToSelector:@selector(setOrientation:)]) {
        objc_msgSend([UIDevice currentDevice], @selector(setOrientation:),    UIInterfaceOrientationLandscapeLeft );
    }

Answer 9

Even though this is not an idle solution, works well for me.

- (void)viewDidLoad
{
   self.view.transform = CGAffineTransformIdentity;
   self.view.transform = CGAffineTransformMakeRotation((M_PI * (90) / 180.0)); 
   self.view.bounds = CGRectMake(0.0, 0.0, 480, 320);
}

Answer 10

As suggested on a related thread shouldAutorotateToInterfaceOrientation is deprecated. Newer apps should leverage the following methods as described in Apple's UIViewController Class Reference until they themselves become deprecated:

• shouldAutorotate ,
• preferredInterfaceOrientationForPresentation ; and
• attemptRotationToDeviceOrientation .

From what I understand it's best to use different View Controllers for views which need to lock into (ie have a preferred) orientation mode which differs from the last.