How apply and move a UIImageView layered above another UIImageView Swift3 - ios

Question

i read here many guides how to create a new image merging two existing ones, using the UIGraphics and the layer.render methods for the two UIImageViews, and finally i can create an then save my new image. The problem is that i can't understand how to put the second UIImageView where i want, at the bottom for example. I 'll post now a image of an merged image and the function that my code run making this possible.
Captured merged photo
And here's my code that do the trick:
extension UIImage {
class func imageWithWatermark(image1: UIImageView, image2: UIImageView) -> UIImage {
UIGraphicsBeginImageContextWithOptions(image1.bounds.size, false, 0.0)
let frame = image1.frame
image2.frame = CGRect(x: 0, y: frame.size.height * 0.80, width: frame.size.width, height: frame.size.height * 0.20 )
image1.layer.render(in: UIGraphicsGetCurrentContext()!)
image2.layer.render(in: UIGraphicsGetCurrentContext()!)
let img = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return img!
}
}
And then my func that saves the merged image:
func addWatermark() {
let newImage = UIImage.imageWithWatermark(image1: cameraPreview, image2: provaImage)
UIImageWriteToSavedPhotosAlbum(newImage, nil,nil,nil)
}

Answer 1

You can use this function which merge two images and the second will be replaces on bottom
func mergeTwoImageSeconInBottom(backgroundImage: UIImage, imageOnBottom: UIImage) -> UIImage {
let size = YOUR_CG_SIZE
UIGraphicsBeginImageContextWithOptions(size, false, 0.0)
backgroundImage.draw(in: CGRect(x: 0, y: 0, width: size.width, height: size.height))
imageOnBottom.draw(at: CGPoint(x: (size.width - imageOnBottom.size.width) / 2, y: size.height - imageOnBottom.size.height))
let newImage: UIImage = UIGraphicsGetImageFromCurrentImageContext()!
UIGraphicsEndImageContext()
return newImage
}