利用blend來改變
// 輸出改變顏色的圖片
extension UIImage {
func imageWithTintColor(tintColor: UIColor) -> UIImage {
UIGraphicsBeginImageContextWithOptions(self.size, false, 0.0)
tintColor.setFill()
let bounds = CGRect(x: 0, y: 0, width: self.size.width, height: self.size.height)
UIRectFill(bounds)
self.draw(in: bounds, blendMode: .destinationIn, alpha: 1.0)
let tintedImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return tintedImage!
}
}
