Changing UIImageView height dynamically while scrolling - ios

Question

I have a question pretty similar to iPhone: Expand UITextView when scrolling
My App is also supposed to have a picture on top of the detail view and a textview below it. When scrolling the picture is supposed to shrink so there is more space for the text. A smilir effect can be found in Music Apps like Shazam or Rdio with the Album-Cover on top and information to the album below.
So far I managed to get the picture to resize by using - (void)scrollViewDidScroll:(UIScrollView *)scrollView, but it is only working if the UIImageView is set to Aspect Fit, I need it to be Aspect Fill though, as I don't want the picture to be squished when resizing the frame.
Can anybody help me achieve that effect?
This is what I used so far. I'm pretty new to programming, so if you have any other comments to the code I write I really appreciate that, too!
Viewcontroller.h
#import <UIKit/UIKit.h>
#interface ViewController : UIViewController < UIScrollViewDelegate>
#property (weak, nonatomic) IBOutlet UIScrollView *scrollView;
#property (weak, nonatomic) IBOutlet UIImageView *imageView;
#property (weak, nonatomic) IBOutlet UITextView *textView;
#end
Viewcontroller.m
#interface ViewController ()
{
CGFloat draggedOffsetY;
CGFloat newHeight;
}
#end
#implementation ViewController
- (void)viewDidLoad
{
[super viewDidLoad];
//UIScrollView *scroll = [[UIScrollView alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height)];
[self.scrollView setContentSize:CGSizeMake(320, 800)];
CGPoint offset = CGPointMake(0, 0);
[self.scrollView setContentOffset:offset];
self.scrollView.delegate = self;
}
- (void)scrollViewDidScroll:(UIScrollView *)scrollView{
draggedOffsetY = self.scrollView.contentOffset.y;
NSLog(#"View was dragged to: %f", draggedOffsetY);
newHeight = self.imageView.frame.size.height-draggedOffsetY;
if (newHeight > 75 && newHeight < 150 ){
[self.imageView setFrame:CGRectMake(0, 0, self.view.frame.size.width, newHeight)];
CGFloat topCoordiate = self.imageView.frame.size.height;
self.textView.frame = CGRectMake(0, topCoordinate, self.textView.frame.size.width, self.textView.frame.size.height);
}
}

Answer 1

If I don't get wrong, I think the reason of the problem is that you don't understant the "Aspect Fit" and "Aspect Fill" yet. With setting to "Aspect Fill", you must change both width and height of imageView to implemetion of image shrink.