Screenshot showing up blank - Swift

Question

Hi I am making a game and I have added a share button to the game. I want the user to be able to share a message, URL, and screenshot along side each other in one message.Th

Answer 1

In WWDC 2015, What's new in UIVisualEffectView, a solution is "glossed over" for capturing a screenshot of a UIVisualEffectView containing a vibrancy label and a blur. The problem that often arises is that Apple's screenshot API tends not to capture the UIVisualEffect, resulting in a screenshot of the view without the visual effect. The solution according to WWDC 2015 involves capturing the snapshot at the window/screen; unfortunately, sample code was not shown. Following is my own implementation:

//create snapshot of the blurView
let window = UIApplication.sharedApplication().delegate!.window!!
//capture the entire window into an image
UIGraphicsBeginImageContextWithOptions(window.bounds.size, false, UIScreen.mainScreen().scale)
window.drawViewHierarchyInRect(window.bounds, afterScreenUpdates: true)
let windowImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
//now position the image x/y away from the top-left corner to get the portion we want
UIGraphicsBeginImageContext(blurView.frame.size)
windowImage.drawAtPoint(CGPoint(x: -blurView.frame.origin.x, y: -blurView.frame.origin.y))
let croppedImage: UIImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext();
//embed image in an imageView, supports transforms.
let resultImageView = UIImageView(image: croppedImage)

Note: This snapshot code will only work once ViewDidAppear has been called.