Marcus Franzen Marcus Franzen - 5 months ago 41
iOS Question

iPad iOS7 - UIImagePickerController in UIPopoverController has wrong preview image

I am using an UIImagePickerController within an UIPopoverController which is working perfectly with iOS6. With iOS 7 the "preview" image which is shown to capture the image is rotated, but if I take a picture it is saved correctly.

This is how I get my picker:

UIImagePickerController *imagePicker = [[UIImagePickerController alloc] init];
imagePicker.delegate = self;
imagePicker.sourceType = UIImagePickerControllerSourceTypeCamera;
imagePicker.mediaTypes = [NSArray arrayWithObjects:
(NSString *) kUTTypeImage,
nil];
imagePicker.allowsEditing = NO;


And add it to a popover controller:

self.imagePickerPopOver = [[UIPopoverController alloc] initWithContentViewController:imagePicker];
[self.imagePickerPopOver presentPopoverFromRect:CGRectMake(aPosViewA.x, cameraButton_y, 100.0, 30.0) inView:self.detailViewController.view permittedArrowDirections:UIPopoverArrowDirectionAny animated:YES];


Those are calculations for the button position at a UIScrollView to show the popover at the correct position:

presentPopoverFromRect:CGRectMake(aPosViewA.x, cameraButton_y, 100.0, 30.0)


I don't think that the problem lies there as I have tried out several combinations.

I have also tried to capture the image in fullscreen-mode, but the app is only allowed to use landscape mode. If the image is taken in portrait-mode and the modal view is dismissed, the app stays in portrait mode as well. I couldn't find a way to prevent the UIImagePickerController to switch to portrait mode or to force the app back to landscape mode if the modal view was dismissed.

UPDATE

I have taken the answer from here and came a step further.

I transform the view after creating the picker and before showing the popover :

switch ([UIApplication sharedApplication].statusBarOrientation) {
case UIInterfaceOrientationLandscapeLeft:
self.imagePicker.view.transform = CGAffineTransformMakeRotation(M_PI/2);
break;
case UIInterfaceOrientationLandscapeRight:
self.imagePicker.view.transform = CGAffineTransformMakeRotation(-M_PI/2);
break;
default:
break;
}


which works as long as i don't turn around the iPad. For that I am registering for the orientation changed event:

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(orientationChanged:) name:UIDeviceOrientationDidChangeNotification object:nil];


and change the picker view:

- (void)orientationChanged:(NSNotification *)notification{

if (self.imagePicker) {
switch ([UIApplication sharedApplication].statusBarOrientation) {
case UIInterfaceOrientationLandscapeLeft:
self.imagePicker.view.transform = CGAffineTransformMakeRotation(M_PI/2);
break;
case UIInterfaceOrientationLandscapeRight:
self.imagePicker.view.transform = CGAffineTransformMakeRotation(-M_PI/2);
break;
default:
break;
}
}
}


REMAINING PROBLEM:
As I wrote in the beginning, when the picture was taken, it was shown correctly to accept or dismiss it. This is now transformed as well. Somehow I need to know when the image is taken and transform it back.

AND, this is really a nasty hack and probably won't work with the next iOS Update. Has anybody an idea how to implement that in a cleaner way?

UPDATE 2

This was too nasty, I have found a cleaner solution which solves my problem but is not the answer to the initial question regarding an imagepicker in a popover controller, which is not recommended by Apple, but allowed.

I have subclassed now the UIImagePickerController like this:

@implementation QPImagePickerController

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation {
return UIInterfaceOrientationIsLandscape(toInterfaceOrientation);
}

- (BOOL)shouldAutorotate {
return YES;
}

- (NSUInteger)supportedInterfaceOrientations{
return UIInterfaceOrientationMaskLandscape;
}

@end


and I am using the imagepicker in fullscreen instead in a popover. Tested so far in iOS7.

Answer

The UIImagePickerController has a property called cameraViewTransform. Applying a CGAffineTransform to this will transform the preview image but will not transform the captured image which will therefore be correctly captured. I have the same problem that you describe and I solved it (for iOS7) by creating my camera controller and placing it in a popover as follows:

UIImagePickerController *imagePickerController = [[UIImagePickerController alloc] init];

[imagePickerController setDelegate:self];

imagePickerController.sourceType = UIImagePickerControllerSourceTypeCamera;

CGFloat scaleFactor=1.3f;

switch ([UIApplication sharedApplication].statusBarOrientation) {

        case UIInterfaceOrientationLandscapeLeft:

            imagePickerController.cameraViewTransform = CGAffineTransformScale(CGAffineTransformMakeRotation(M_PI * 90 / 180.0), scaleFactor, scaleFactor);

            break;

        case UIInterfaceOrientationLandscapeRight:

            imagePickerController.cameraViewTransform = CGAffineTransformScale(CGAffineTransformMakeRotation(M_PI * -90 / 180.0), scaleFactor, scaleFactor);

            break;

        case UIInterfaceOrientationPortraitUpsideDown:

            imagePickerController.cameraViewTransform = CGAffineTransformMakeRotation(M_PI * 180 / 180.0);

            break;

            default:
                break;
        }

 __popoverController = [[UIPopoverController alloc] initWithContentViewController:imagePickerController];

[__popoverController presentPopoverFromRect:presentationRect inView:self.view permittedArrowDirections:UIPopoverArrowDirectionAny animated:YES];

I also scale the image when in Landscape so that it fills the viewfinder more than it otherwise would. To my mind this is all rather nasty, but I will hopefully be able to remove it once iOS7.1 arrives.

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