UIImageWriteToSavedPhotosAlbum save as PNG with transparency?

Question

I\'m using UIImageWriteToSavedPhotosAlbum to save a UIImage to the user\'s photo album. The problem is that the image doesn\'t have transparency and is a JPG. I\'ve got the

Answer 1

As an alternative to creating a secondary UIImage for UIImageWriteToSavedPhotosAlbum the PNG data can be written directly using the PHPhotoLibrary.

Here is a UIImage extension named 'saveToPhotos' which does this:

extension UIImage {

    func saveToPhotos(completion: @escaping (_ success:Bool) -> ()) {

        if let pngData = self.pngData() {

            PHPhotoLibrary.shared().performChanges({ () -> Void in

                let creationRequest = PHAssetCreationRequest.forAsset()
                let options = PHAssetResourceCreationOptions()

                creationRequest.addResource(with: PHAssetResourceType.photo, data: pngData, options: options)

            }, completionHandler: { (success, error) -> Void in

                if success == false {

                    if let errorString = error?.localizedDescription  {
                        print("Photo could not be saved: \(errorString))")
                    }

                    completion(false)
                }
                else {
                    print("Photo saved!")

                    completion(true)
                }
            })
        }
        else {
            completion(false)
        }

    }
}

To use:

    if let image = UIImage(named: "Background.png") {
        image.saveToPhotos { (success) in
            if success {
                // image saved to photos
            }
            else {
                // image not saved
            }
        }
    }