How to resize the UIImageView after AspectFit ratio - ios

Question

How do I resize UIImageView after setting its contentmode to UIViewContentModeScaleAspectFit so that i can remove the white spaces from top & below.
Please see the attached image
Thanks in advance:)

Answer 1

Hope this will help some others as well ,please do comment if it will break in some condition :)
- (CGRect)frameForImageattribute:(CGSize)image inImageViewAspectFit:(UIImageView *)imageView {
float imageRatio = image.width / image.height;
float viewRatio = imageView.frame.size.width / imageView.frame.size.height;
if (imageRatio < viewRatio) {
float scale = imageView.frame.size.height / image.height;
float width = scale * image.width;
return CGRectMake(kLeftPading, kTopPading, width, imageView.frame.size.height);
}
else {
float scale = imageView.frame.size.width / image.width;
float height = scale * image.height;
return CGRectMake(kLeftPading, kTopPading, imageView.frame.size.width, height);
}
}

Answer 2

You need to get the scale factor of the image view. it can be obtained by
float scaleFactor = MAX(image.size.width/imageView.bounds.size.width, image.size.height/imageView.bounds.size.height);
Then do
CGRect ivFrame = imageView.frame;
ivframe.size.height = image.size.height/scalefactor;
ivFrame.size.width = image.size.width/scalefactor;
imageView.frame = ivFrame;
theres probably a category out there that does this automagically.
EDIT: Heres one for the scalefactor calculation, and it even respects the content mode of the mageView:
how can I get the scale factor of a UIImageView who's mode is AspectFit?

Answer 3

If you know only the width of the imageview and when the height of the image is dynamic then you need to scale the image's height according to the given width to remove the white spaces above and below your image in UIViewContentModeScaleAspectFit mode. Use the following method from here to scale the height of the image according to the standard width of your screen.
-(UIImage*)imageWithImage: (UIImage*) sourceImage scaledToWidth: (float) i_width
{
float oldWidth = sourceImage.size.width;
float scaleFactor = i_width / oldWidth;
float newHeight = sourceImage.size.height * scaleFactor;
float newWidth = oldWidth * scaleFactor;
UIGraphicsBeginImageContext(CGSizeMake(newWidth, newHeight));
[sourceImage drawInRect:CGRectMake(0, 0, newWidth, newHeight)];
UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return newImage;
}
And call it from your cellForRowAtIndexPath: method like this:
UIImage *img = [dictImages objectForKey:yourImageKey]; // loaded the image
cell.imgView.image = [self imageWithImage:img scaledToWidth:self.view.frame.size.width];