how to set a background color in UIimage in swift programming

You can also use this extension:

    extension UIImage {
        func imageWithColor(tintColor: UIColor) -> UIImage {
            UIGraphicsBeginImageContextWithOptions(self.size, false, self.scale)

            let context = UIGraphicsGetCurrentContext()!
            context.translateBy(x: 0, y: self.size.height)
            context.scaleBy(x: 1.0, y: -1.0);
            context.setBlendMode(.normal)

            let rect = CGRect(x: 0, y: 0, width: self.size.width, height: self.size.height) as CGRect
            context.clip(to: rect, mask: self.cgImage!)
            tintColor.setFill()
            context.fill(rect)

            let newImage = UIGraphicsGetImageFromCurrentImageContext()!
            UIGraphicsEndImageContext()

            return newImage
        }
    }

And then

image.imageWithColor("#1A6BAE".UIColor)

EDIT: 2019-11: Updated to Swift 5 by @Yuto

Updated @Egghead's solution for Swift 3

extension UIImage {
   static func imageWithColor(tintColor: UIColor) -> UIImage {
        let rect = CGRect(x: 0, y: 0, width: 1, height: 1)
        UIGraphicsBeginImageContextWithOptions(rect.size, false, 0)
        tintColor.setFill()
        UIRectFill(rect)
        let image: UIImage = UIGraphicsGetImageFromCurrentImageContext()!
        UIGraphicsEndImageContext()
        return image
    }
}

Usage :

UIImage.imageWithColor(tintColor: <Custom color>)

Swift 5, 4

If you need to draw the background of an image, for optimization and decorative purposes, you can draw the image in a specific way:

UIImage(named: "someImage")?.withBackground(color: .white)

---

Extension

extension UIImage {
  func withBackground(color: UIColor, opaque: Bool = true) -> UIImage {
    UIGraphicsBeginImageContextWithOptions(size, opaque, scale)
        
    guard let ctx = UIGraphicsGetCurrentContext(), let image = cgImage else { return self }
    defer { UIGraphicsEndImageContext() }
        
    let rect = CGRect(origin: .zero, size: size)
    ctx.setFillColor(color.cgColor)
    ctx.fill(rect)
    ctx.concatenate(CGAffineTransform(a: 1, b: 0, c: 0, d: -1, tx: 0, ty: size.height))
    ctx.draw(image, in: rect)
        
    return UIGraphicsGetImageFromCurrentImageContext() ?? self
  }
}