How to lock screen in portrait/landscape in iPhone?

Question

My Application supports all orientation but in few cases i want to lock the screen in

portrait/landscape mode.

In my Application i have two kind of pdf docum

Answer 1

For iOS6+, you could add this to your controller:

- (BOOL)shouldAutorotate {
    YES;
}

- (NSUInteger)supportedInterfaceOrientations {

  if (<PDF is portrait>)
    return UIInterfaceOrientationMaskPortrait;
  if (<PDF is landscape>)
    return UIInterfaceOrientationMaskLandscape;

  return UIInterfaceOrientationMaskAll;

}

Hope this helps.

EDIT:

I am not sure if you need to manually rotate the PDF to get the results you want. In this case you might try with something like:

- (void)willRotateToInterfaceOrientation:(UIInterfaceOrientation)toOrientation
                            duration:(NSTimeInterval)duration {

    if (toOrientation == UIInterfaceOrientationMaskLandscape)
        pdfScrollViewFrame.transform = CGAffineTransformMakeRotation(M_PI/2);

    … // handle all other cases here
}

In order to only lock rotation after viewDidAppear, I would do following:

@interface…
…
   @property (nonatomic) BOOL isRotationLocked;
…
@end

@implementation…
…
- (void)viewDidAppear:(BOOL)animated {
  …
  self.isRotationLocked = YES;
}

- (BOOL)shouldAutorotate {
    YES;
}

- (NSUInteger)supportedInterfaceOrientations {

  if (self.isRotationLocked) {
    if (<PDF is portrait>)
      return UIInterfaceOrientationMaskPortrait;
    if (<PDF is landscape>)
      return UIInterfaceOrientationMaskLandscape;
  }
  return UIInterfaceOrientationMaskAll;

}
…