UIImageView aspect fit and center

Question

I have an image view, declared programmatically, and I am setting its image, also programmatically.

However, I find myself unable to set the image to both fit the as

Answer 1

This subclass uses center if the image is not larger than the view, otherwise it scales down. I found this useful for a UIImageView that changes the size.

The image it displays is smaller than the view for large sizes, but larger than the view for small sizes. I want it only to scale down, but not up.

class CenterScaleToFitImageView: UIImageView {
    override var bounds: CGRect {
        didSet {
            adjustContentMode()
        }
    }

    override var image: UIImage? {
        didSet {
            adjustContentMode()
        }
    }

    func adjustContentMode() {
        guard let image = image else {
            return
        }
        if image.size.width > bounds.size.width ||
            image.size.height > bounds.size.height {
            contentMode = .ScaleAspectFit
        } else {
            contentMode = .Center
        }
    }
}

Answer 2

In swift language we can set content mode of UIImage view like following as:

let newImgThumb = UIImageView(frame: CGRect(x: 10, y: 10, width: 100, height: 100))
newImgThumb.contentMode = .scaleAspectFit

Answer 3

Swift

yourImageView.contentMode = .center

You can use the following options to position your image:

• scaleToFill
• scaleAspectFit // contents scaled to fit with fixed aspect. remainder is transparent
• redraw // redraw on bounds change (calls -setNeedsDisplay)
• center // contents remain same size. positioned adjusted.
• top
• bottom
• left
• right
• topLeft
• topRight
• bottomLeft
• bottomRight

Answer 4

I solved this problem like this.

1. setImage to UIImageView (with UIViewContentModeScaleAspectFit)
2. get imageSize (CGSize imageSize = imageView.image.size)
3. UIImageView resize. [imageView sizeThatFits:imageSize]
4. move position where you want.

I wanted to put UIView on the top center of UICollectionViewCell. so, I used this function.

- (void)setImageToCenter:(UIImageView *)imageView
{
    CGSize imageSize = imageView.image.size;
    [imageView sizeThatFits:imageSize];
    CGPoint imageViewCenter = imageView.center;
     imageViewCenter.x = CGRectGetMidX(self.contentView.frame);
    [imageView setCenter:imageViewCenter];
}

It works for me.

Answer 5

Just pasting the solution:

Just like @manohar said

imageView.contentMode = UIViewContentModeCenter;
if (imageView.bounds.size.width > ((UIImage*)imagesArray[i]).size.width && imageView.bounds.size.height > ((UIImage*)imagesArray[i]).size.height) {
       imageView.contentMode = UIViewContentModeScaleAspectFit;
}

solved my problem

Answer 6

You can achieve this by setting content mode of image view to UIViewContentModeScaleAspectFill.

Then use following method method to get the resized uiimage object.

- (UIImage*)setProfileImage:(UIImage *)imageToResize onImageView:(UIImageView *)imageView
{
    CGFloat width = imageToResize.size.width;
    CGFloat height = imageToResize.size.height;
    float scaleFactor;
    if(width > height)
    {
        scaleFactor = imageView.frame.size.height / height;
    }
    else
    {
        scaleFactor = imageView.frame.size.width / width;
    }

    UIGraphicsBeginImageContextWithOptions(CGSizeMake(width * scaleFactor, height * scaleFactor), NO, 0.0);
    [imageToResize drawInRect:CGRectMake(0, 0, width * scaleFactor, height * scaleFactor)];
    UIImage *resizedImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();

    return resizedImage;
}

Edited Here (Swift Version)

func setProfileImage(imageToResize: UIImage, onImageView: UIImageView) -> UIImage
{
    let width = imageToResize.size.width
    let height = imageToResize.size.height

    var scaleFactor: CGFloat

    if(width > height)
    {
        scaleFactor = onImageView.frame.size.height / height;
    }
    else
    {
        scaleFactor = onImageView.frame.size.width / width;
    }

    UIGraphicsBeginImageContextWithOptions(CGSizeMake(width * scaleFactor, height * scaleFactor), false, 0.0)
    imageToResize.drawInRect(CGRectMake(0, 0, width * scaleFactor, height * scaleFactor))
    let resizedImage = UIGraphicsGetImageFromCurrentImageContext()
    UIGraphicsEndImageContext()

    return resizedImage;
}