Swift iOS中的屏幕截图？

Question

如何通过代码(在Swift中)从我的屏幕截取屏幕截图并保存？我可以截取屏幕并将其保存为图像吗？

我看了,我看到了这段代码,但我不能使用它(我认为),因为它没有做任何事情.

var screen = UIScreen.mainScreen()
snapshotVieww = screen.snapshotViewAfterScreenUpdates(false)
UIGraphicsBeginImageContextWithOptions(screen.bounds.size, false, 0)
snapshotVieww.drawViewHierarchyInRect(view.bounds, afterScreenUpdates: true)
var image:UIImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
provino = UIImageView(image: image)

Answer 1

使用Swift 4/iOS 10.3,您可以选择以下方法之一来解决您的问题.

1.截取视图控制器视图的屏幕截图

以下代码显示如何截取屏幕截图并将其保存在设备相册中:

import UIKit

class ViewController: UIViewController {

    /* ... */

    @IBAction func screenshot(_ sender: UIBarButtonItem) {
        //Create the UIImage
        UIGraphicsBeginImageContextWithOptions(view.frame.size, true, 0)
        guard let context = UIGraphicsGetCurrentContext() else { return }
        view.layer.render(in: context)
        guard let image = UIGraphicsGetImageFromCurrentImageContext() else { return }
        UIGraphicsEndImageContext()

        //Save it to the camera roll
        UIImageWriteToSavedPhotosAlbum(image, nil, nil, nil)
    }

}

请注意,此代码的结果将是.JPG图像.另请注意,导航栏和状态栏不会出现在最终图像中.

从iOS 10开始,作为上一代码的替代品,您可以使用以下代码:

import UIKit

class ViewController: UIViewController {

    /* ... */

    @IBAction func screenshot(_ sender: UIBarButtonItem) {
        //Create the UIImage
        let renderer = UIGraphicsImageRenderer(size: view.frame.size)
        let image = renderer.image(actions: { context in
            view.layer.render(in: context.cgContext)
        })

        //Save it to the camera roll
        UIImageWriteToSavedPhotosAlbum(image, nil, nil, nil)
    }

}

2.截取iPhone窗口的屏幕截图

如果要拍摄包含导航栏(但不是状态栏)的屏幕截图,可以使用以下代码:

import UIKit

class ViewController: UIViewController {

    /* ... */

    @IBAction func screenshot(_ sender: UIBarButtonItem) {
        //Create the UIImage
        guard let layer = UIApplication.shared.keyWindow?.layer else { return }
        UIGraphicsBeginImageContextWithOptions(layer.frame.size, true, 0)
        guard let context = UIGraphicsGetCurrentContext() else { return }
        layer.render(in: context)
        guard let image = UIGraphicsGetImageFromCurrentImageContext() else { return }
        UIGraphicsEndImageContext()

        //Save it to the camera roll
        UIImageWriteToSavedPhotosAlbum(image, nil, nil, nil)
    }

}

从iOS 10开始,作为上一代码的替代品,您可以使用以下代码:

import UIKit

class ViewController: UIViewController {

    /* ... */

    @IBAction func screenshot(_ sender: UIBarButtonItem) {
        //Create the UIImage
        guard let layer = UIApplication.shared.keyWindow?.layer else { return }
        let renderer = UIGraphicsImageRenderer(size: layer.frame.size)
        let image = renderer.image(actions: { context in
            layer.render(in: context.cgContext)
        })

        //Save it to the camera roll
        UIImageWriteToSavedPhotosAlbum(image, nil, nil, nil)
    }

}

提醒

从iOS 10开始,为了防止您的应用在调用screenshot(_:)方法时崩溃,您需要将密钥添加NSPhotoLibraryUsageDescription到项目的Info.plist文件中:

<key>NSPhotoLibraryUsageDescription</key>
<string>Some description to explain why access is required</string>

Answer 2

只需这几行代码就可以获得View的screenShot :(刚刚测试过)

  UIGraphicsBeginImageContextWithOptions(UIScreen.mainScreen().bounds.size, false, 0);
  self.view.drawViewHierarchyInRect(view.bounds, afterScreenUpdates: true)
  var image:UIImage = UIGraphicsGetImageFromCurrentImageContext();

  UIGraphicsEndImageContext();

  self.imgView.image = image;