ios UINavigationController中强制只有一个viewcontroller 为 landscape 模式

 

竖屏模式代码

 

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation{
    return (toInterfaceOrientation == UIInterfaceOrientationPortrait);
}
-(BOOL)shouldAutorotate {
    return YES;
}
- (NSUInteger)supportedInterfaceOrientations {
    return UIInterfaceOrientationMaskPortrait;
}

 

 

同样的，横屏模式一样的代码

 

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation{
    return (toInterfaceOrientation == UIInterfaceOrientationLandscapeLeft);
}
-(BOOL)shouldAutorotate {
    return YES;
}
- (NSUInteger)supportedInterfaceOrientations {
    return UIInterfaceOrientationMaskLandscapeLeft;
}

 

Every view controller pushed onto the navigation controllers stack have to support the same orientations. This means that it is not possible to have some view controllers only supporting portrait and others only supporting landscape. In other words all view controllers on the same navigation controller stack should return the same in the delegate:

 

(BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation

 

 

But there is a simple solution to this! Here is an example for going from portrait to landscape. Here is the steps to do it and below is code to support it.

 

1. Create a ‘fake’ view controller that will be root in a sub navigation controller. 

    This view controller should support landscape.

2. Create a new instance of a UINavigationController, add an instance of the ‘fake’ view      controller as root and an instance of your landscape view controller as second view controller

3. Present the UINavigationController instance as modal from the parent view controller

 

First, create a new view controller (FakeRootViewController) with this code:

 

interface FakeRootViewController : UIViewController
@property (strong, nonatomic) UINavigationController* parentNavigationController;
@end

@implementation FaceRootViewController
@synthesize parentNavigationController;
// viewWillAppear is called when we touch the back button on the navigation bar
(void)viewWillAppear:(BOOL)animated {
  // Remove our self from modal view though the parent view controller
  [parentNavigationController dismissModalViewControllerAnimated:YES];
}
(BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {
   return (interfaceOrientation == UIInterfaceOrientationIsLandscape(interfaceOrientation));
} 

 

Here is the code to present the view controller that you wish to show in landscape mode:

 

FakeRootViewController* fakeRootViewController = [[FakeRootViewController alloc] init];[fakeRootViewController.navigationItem setBackBarButtonItem:backButton]; // Set back button
// The parent navigation controller is the one containing the view controllers in portrait mode.
fakeRootViewController.parentNavigationController = parentNavigationController;

UINavigationController* subNavigationController = // Initialize this the same way you have initialized your parent navigation controller.

UIViewController* landscapeViewController = // Initialize the landscape view controller

[subNavigationController setViewControllers:
   [NSArray arrayWithObjects:fakeRootViewController, 
                                               landscapeViewController, nil] animated:NO];

[_navigationController presentModalViewController:subNavigationController animated:YES];

 

Remember that the landscapeViewController should also have this implementation:

(BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {
   return (interfaceOrientation == UIInterfaceOrientationIsLandscape(interfaceOrientation));
}