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Pablo Ezequiel Inchausti
Asked: 2020-08-06 18:11:30 +0800 CST 2020-08-06 18:11:30 +0800 CST

Resize an image while keeping the ratio [Objective-C]

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I have an object with an image and I would need to modify the dimensions of the image to a certain height (example 50px), but keeping the scale (the ratios).

UIImage *thumbImage = [UIImage imageNamed:@"peon.png"];

What would be a function that can do this?

objective-c

2 Answers

  1. Best Answer

    You can use this function, for example:

    + (UIImage *)imageWithImage:(UIImage *)image scaledToHeight:(CGFloat)newHeight {

    CGFloat scaleFactor = newHeight / image.size.height;
    CGFloat newWidth = image.size.width * scaleFactor;

    UIGraphicsBeginImageContext(CGSizeMake(newWidth, newHeight));
    [image drawInRect:CGRectMake(0.0, 0.0, newWidth, newHeight)];
    UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();

    return newImage;

}
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  2. I would recommend using Assets.xcassets, you have to put the image and then when assigning the image just like this UIImage *thumbImage = [UIImage imageNamed:@"pawn"];You add for each size you need

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