细节
- Xcode 9.3,Swift 4.1
- Xcode 10.2(10E125)和11.0(11A420a),Swift 5
在iOS上测试:9、10、11、12、13
解
import UIKit
extension UIApplication {
func getKeyWindow() -> UIWindow? {
if #available(iOS 13, *) {
return windows.first { $0.isKeyWindow }
} else {
return keyWindow
}
}
func makeSnapshot() -> UIImage? { return getKeyWindow()?.layer.makeSnapshot() }
}
extension CALayer {
func makeSnapshot() -> UIImage? {
let scale = UIScreen.main.scale
UIGraphicsBeginImageContextWithOptions(frame.size, false, scale)
defer { UIGraphicsEndImageContext() }
guard let context = UIGraphicsGetCurrentContext() else { return nil }
render(in: context)
let screenshot = UIGraphicsGetImageFromCurrentImageContext()
return screenshot
}
}
extension UIView {
func makeSnapshot() -> UIImage? {
if #available(iOS 10.0, *) {
let renderer = UIGraphicsImageRenderer(size: frame.size)
return renderer.image { _ in drawHierarchy(in: bounds, afterScreenUpdates: true) }
} else {
return layer.makeSnapshot()
}
}
}
extension UIImage {
convenience init?(snapshotOf view: UIView) {
guard let image = view.makeSnapshot(), let cgImage = image.cgImage else { return nil }
self.init(cgImage: cgImage, scale: image.scale, orientation: image.imageOrientation)
}
}
用法
imageView.image = UIApplication.shared.makeSnapshot()
imageView.image = view.makeSnapshot()
imageView.image = view.layer.makeSnapshot()
imageView.image = UIImage(snapshotOf: view)
旧解决方案
Xcode 8.2.1,快速3
适用于iOS 10x的版本1
import UIKit
extension UIApplication {
var screenShot: UIImage? {
if let layer = keyWindow?.layer {
let scale = UIScreen.main.scale
UIGraphicsBeginImageContextWithOptions(layer.frame.size, false, scale);
if let context = UIGraphicsGetCurrentContext() {
layer.render(in: context)
let screenshot = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return screenshot
}
}
return nil
}
}
适用于iOS 9x,10x的版本2
如果您尝试在iOS 9x中使用版本1代码, 则会出现错误:CGImageCreateWithImageProvider:无效的图像提供程序:NULL。
import UIKit
extension UIApplication {
var screenShot: UIImage? {
if let rootViewController = keyWindow?.rootViewController {
let scale = UIScreen.main.scale
let bounds = rootViewController.view.bounds
UIGraphicsBeginImageContextWithOptions(bounds.size, false, scale);
if let _ = UIGraphicsGetCurrentContext() {
rootViewController.view.drawHierarchy(in: bounds, afterScreenUpdates: true)
let screenshot = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return screenshot
}
}
return nil
}
}
用法
let screenShot = UIApplication.shared.screenShot!