How to change the color of a UIImage in Swift

Question

I'm in swift and I'm trying to generate a function that takes in a UIImage and a UIColor and returns a UIImage recolored

I'm not working with a UIImageView, these are simply UIImages that I intend to use as icons. Is there any good way to implement this?

Answer 1

edit/update:

For iOS10+ we can use UIGraphicsImageRenderer:

Xcode 11 • Swift 5.1

extension UIImage {
    func tinted(with color: UIColor, isOpaque: Bool = false) -> UIImage? {
        let format = imageRendererFormat
        format.opaque = isOpaque
        return UIGraphicsImageRenderer(size: size, format: format).image { _ in
            color.set()
            withRenderingMode(.alwaysTemplate).draw(at: .zero) 
        }
    }
}

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Playground Testing

let camera = UIImage(data: try! Data(contentsOf: URL(string: "https://cdn4.iconfinder.com/data/icons/ionicons/512/icon-camera-128.png")!))!
let redCamera = camera.tinted(with: .red)

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original answer

You can use UIGraphicsBeginImageContextWithOptions to begin an image context, set the desired color and use image's method func draw(in rect: CGRect) to draw your icon image using rendering mode .alwaysTemplate on it:

extension UIImage {
    func tinted(with color: UIColor) -> UIImage? {
        UIGraphicsBeginImageContextWithOptions(size, false, scale)
        defer { UIGraphicsEndImageContext() }
        color.set()
        withRenderingMode(.alwaysTemplate)
            .draw(in: CGRect(origin: .zero, size: size))
        return UIGraphicsGetImageFromCurrentImageContext()
    }
}

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