How to fill the background with image in landscape in IOS? - ios

Question

What I'm doing is creating filling in a view's background with an image returned from a UIImagePickerController. The image fills fine in portrait mode; however, the image will repeat when filled as background in landscape mode, but I have no idea why this is occuring. This is a private method I use to resize my image.
+ (UIImage *)imageWithImage:(UIImage *)image scaledToSize:(CGSize)newSize landscape:(BOOL)landscape {
UIGraphicsBeginImageContextWithOptions(newSize, NO, 0.0);
[image drawInRect:CGRectMake(0, 0, newSize.width, newSize.height)];
UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return newImage;
}
When this method is called the newsize parameter is equal to the views bounds size (self.view.bounds.size). The size is accessed after the view's transformation to landscape, but the image doesn't properly.
This is the code that is called right after getting an image from the UIImagePickerController.
-(void) imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info
{
UIImage *image = [info objectForKey:UIImagePickerControllerOriginalImage];
if (image.size.width > image.size.height) {
self.view.transform = CGAffineTransformRotate(self.view.transform, M_PI_2);
self.composition.landscapemode = YES;
} else {
self.composition.landscapemode = NO;
}
self.composition.image = [NewCompositionViewController imageWithImage:image scaledToSize:self.view.bounds.size landscape:self.composition.landscapemode];
self.view.backgroundColor = [UIColor colorWithPatternImage:self.composition.image];
[self dismissViewControllerAnimated:YES completion:nil];
}

Answer 1

[UIColor colorWithPatternImage:] is meant for tiling images, so it's behaving as it should.
I would recommend creating a UIImageView with screen-sized frame, setting an image to it, and adding it as subview:
UIImageView *backgroundImage = [[UIImageView alloc] initWithFrame:self.view.frame];
[backgroundImage setImage:self.composition.image];
// choose best mode that works for you
[backgroundImage setContentMode:UIViewContentModeScaleAspectFill];
[self.view insertSubview:backgroundImage atIndex:0];
//OR
[self.view addSubview:backgroundImage];
[self.view sendSubviewToBack:backgroundImage];
once it's added, you can rotate it and experiment with autoresizing masks to make sure it's displayed properly for all orientations. Exact method would depend on if you are using auto-layout or not.

Answer 2

UIViewContentModeScaleAspectFill may be more appropriate here than UIViewContentModeScaleAspectFit since the image is filling a background view. AspectFit will maintain the image's aspect ratio and make the entire image fit in the space, which may leave portions of the view transparent. AspectFill also maintains aspect ratio, but will fill the entire view and clip any portions of the image that don't match the view bounds.

Answer 3

I've been able to apply an "aspect fit" UIImage to a UIView background by combining a few AVFoundation and UIKit APIs. Here's one example:
UIImage *image = [UIImage imageWithContentsOfFile:self.desiredBackgroundImageFilePathString];
UIGraphicsBeginImageContext(self.drawingImage.frame.size);
[image drawInRect:AVMakeRectWithAspectRatioInsideRect(image.size, self.drawingImage.bounds)];
image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
self.drawingImage.backgroundColor = [UIColor colorWithPatternImage:image];
This flows through a few simple, but important steps:
Generate a UIImage from a file (or whatever).
Define the context of the image (the desired UIView for the background) with UIGraphicsBeginImageContext().
Use drawInRect in combination with AVMakeRectWithAspectRatioInsideRect to scale the image. Provide AVMakeRect...() with the image's .size and the bounds of the target UIView.
Apply the resized image to the desired image context.
Apply your now-resized image to the .backgroundColor of the target UIView using colorWithPatternImage.
I'm able to swap out images with both landscape and portrait aspect ratios without alignment or clipping issues using this code.