UIImage Extension Not Working Properly

Question

So I am trying to set custom icons for tabBarItems in my project (because the default options are quite limited).

Apparently the icons are not automatically adjusted to be 30 x 30 as they need to be so I've been trying to do it manually using a UIImage extension. I have only used extensions once or twice, and all that I am really trying to do is convert this answer into Swift 3. My attempt for the extension is below:

extension UIImage {

    func scaledToSize(size: CGSize) -> UIImage {
        UIGraphicsBeginImageContextWithOptions(size, false, 0.0)
        images?[0].draw(in: CGRect(x: 0, y: 0, width: size.width, height: size.height))
        let image = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()
        return image!
    }

}

If it is not clear, this extension is supposed to be used like this to achieve my purpose:

self.tabBarItem.image = tabBarItemImage?.scaledToSize(size: CGSize(width: 30, height: 30))

I understand that this isn't the most elegant solution as-is, but I thought it would work and it isn't. I have tried using it with a simple imageView, but it doesn't work with that either so I don't think it is an issue with using this technique with the tabBarItems specifically.

If anyone could point out what I am doing wrong or guide me in the right direction that would be much appreciated.

Answer 1

try below extension,

extension UIImageView {
    func scaledToSize(size: CGSize){
        UIGraphicsBeginImageContextWithOptions(size, false, 0.0)
        self.image!.draw(in: CGRect(x: 0, y: 0, width: size.width, height: size.height))
        let imageed = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()
        self.image = imageed
    }
}