强制iOS设备更改方向

Question

First of all, I would like to apologize for asking the same question again which has been asked in this forum many times. But, my problem is that I've tried all the suggested solutions but still I haven't got a solution to my problem.

I have a ViewControllerA in Potrait mode and ViewControllerB in landscape mode. When the device changes from potrait to landscape, i can see ViewControllerB opening in landscape mode, but when the device is rotated back to potrait mode, ViewControllerA is displayed but still in landscape mode. Could anybody help me understand how can I display it back in potrait mode?

I have tried following things but nothing worked for me:

Added following code in ViewControllerA in viewWillAppear :

[[UIApplication sharedApplication] setStatusBarOrientation:UIInterfaceOrientationPortrait];

Have also added following functions in this view controller:

- (BOOL)shouldAutorotate
{
    return NO;
}

- (NSUInteger)supportedInterfaceOrientations
{
   return UIInterfaceOrientationMaskPortrait;
}

- (UIInterfaceOrientation)preferredInterfaceOrientationForPresentation
{
     return UIInterfaceOrientationPortrait;
}

Answer 1

Hope this helps you by using supportedInterfaceOrientationsForWindow

Appdelegate.h

@property () BOOL restrictRotation;

in Appdelegate.m

  -(NSUInteger)application:(UIApplication *)application supportedInterfaceOrientationsForWindow:(UIWindow *)window
{
    //restrictRotation is BOOL value
     if(self.restrictRotation)//set the bool value to view controller which you want to load in landscape
          return UIInterfaceOrientationMaskLandscape;
     else
       return UIInterfaceOrientationMaskAll;
}

//call this where you need

requiredViewController.m

-(void) restrictRotation:(BOOL) restriction
{

  appDelegate = (AppDelegate*)[UIApplication sharedApplication].delegate;
  appDelegate.restrictRotation = restriction;
}

//In ViewdidLoad()

- (void)viewDidLoad
 {
   [super viewDidLoad];
   [self restrictRotation:YES];//Set YES if required in Landscape mode
 }

Answer 2

请试试

[[UIDevice currentDevice] setValue:[NSNumber numberWithInteger:UIInterfaceOrientationPortrait] forKey:@"orientation"];

Answer 3

Use below code

-(void) viewDidAppear:(BOOL)animated
{
[UIViewController attemptRotationToDeviceOrientation];
[super viewDidAppear:animated];
}

& also in viewWIllAppear write

[UIDevice currentDevice] setValue:[NSNumber numberWithInteger:UIInterfaceOrientationPortrait] forKey:@"orientation"]