Question

I have secondViewController that can display content in both landscape and portrait view. The MainViewController (parent of secondViewController) can only display content in landscape mode.

When SecondView is in portrait mode and is pop out, the view the MainViewController (which is supposed to display content in landscape mode only) displays content in portrait. It does not refresh to landscape mode.

Is there a way to force MainViewController to refresh the content?

On the MainViewController’s viewWillAppear method, I have added setNeedsDisplay and layoutSubviews, etc.

-(void) viewWillAppear:(BOOL)animated {
    [self.view setNeedsDisplay];
    [self.view layoutIfNeeded];
    [self.view layoutSubviews];
}

but it is not reloading the view. I also tried the navigation controller’s delegate method – willShowViewController but its not working.

Answer 1

Looks like if you remove the view and add it back it works

UIDeviceOrientation orientation = [[UIDevice currentDevice] orientation];
if (UIDeviceOrientationIsPortrait(orientation)){        
    NSLog(@"force to landscape mode ");
    UIWindow *window = [[UIApplication sharedApplication] keyWindow];
    UIView *view = [window.subviews objectAtIndex:0];
    [view removeFromSuperview];
    [window addSubview:view];        
}

You can also use CGAffineTransformMakeRotation but it the rotation does not work on the navigation controller

    if (orientation == UIDeviceOrientationPortraitUpsideDown) {
        [self.view setTransform:CGAffineTransformMakeRotation(M_PI/-2.0)];
        //[self.navigationController.view setTransform:CGAffineTransformMakeRotation(M_PI/-2.0)];
    } else if (orientation == UIDeviceOrientationPortrait) {
        [self.view setTransform:CGAffineTransformMakeRotation(M_PI/2.0)];
        //[self.navigationController.view setTransform:CGAffineTransformMakeRotation(M_PI/-2.0)];
    }