如何捕获WKWebview的完整页面截图？

Question

我可以捕捉调整UIWebView的UIScrollView的框架UIWebView的所有内容截屏。但是，我不能用同样的方法捕捉WKWebView的所有内容截屏。

我用来捕捉UIWebView如下的方法：

1. 备份帧和webview.scrollView的上海华
2. 创建一个新的容器视图webview.scrollView是上海华
3. 调整的新容器视图和webview.scrollView帧。帧是相同的，以webview.scrollView.contentSize
4. 通过renderInContext或drawViewHierarchyInRect画

然而，这种方法将捕获WKWebview的白色屏幕截图。这是行不通的！

我有打印WKWebView的所有级别，然后我发现了一个UIView（WKContentView）的大小是相同的，以内容查看，你可以发现这个水平这一观点：

• WKWebView WKScrollView WKContentView（大小是相同的，以内容查看）

我也有尝试WKContentView捕捉到，然后我发现唯一可见的视图可以被捕获。

无论如何，任何人都可以告诉我如何捕获WKWebView一整页内容截屏？

Answer 1

请参阅本answer

iOS的11.0及以上，苹果已经提供了以下API捕捉WKWebView的快照。

@available(iOS 11.0, *)
    open func takeSnapshot(with snapshotConfiguration: WKSnapshotConfiguration?, completionHandler: @escaping (UIImage?, Error?) -> Swift.Void)

Answer 2

迅速3时，Xcode 8

func takeScreenshot() -> UIImage? { 
    let currentSize = webView.frame.size
    let currentOffset = webView.scrollView.contentOffset

    webView.frame.size = webView.scrollView.contentSize
    webView.scrollView.setContentOffset(CGPoint.zero, animated: false)

    let rect = CGRect(x: 0, y: 0, width: webView.bounds.size.width, height: webView.bounds.size.height)
    UIGraphicsBeginImageContextWithOptions(rect.size, false, UIScreen.main.scale)
    webView.drawHierarchy(in: rect, afterScreenUpdates: true)
    let image = UIGraphicsGetImageFromCurrentImageContext()
    UIGraphicsEndImageContext()

    webView.frame.size = currentSize
    webView.scrollView.setContentOffset(currentOffset, animated: false)

    return image
}

Answer 3

- Xcode的10 SWIFT 4.2 -

用这个;

//这是取截屏按钮

   @IBAction func snapShot(_ sender: Any) {

       captureScreenshot()
    }

//这是这是手柄的截图功能的功能。

func captureScreenshot(){
    let layer = UIApplication.shared.keyWindow!.layer
    let scale = UIScreen.main.scale
    // Creates UIImage of same size as view
    UIGraphicsBeginImageContextWithOptions(layer.frame.size, false, scale);
    layer.render(in: UIGraphicsGetCurrentContext()!)
    let screenshot = UIGraphicsGetImageFromCurrentImageContext()
    UIGraphicsEndImageContext()
    // THIS IS TO SAVE SCREENSHOT TO PHOTOS
    UIImageWriteToSavedPhotosAlbum(screenshot!, nil, nil, nil)
}

并且必须添加在您的info.plist这些键;

 key value = "Privacy - Photo Library Additions Usage Description" ,
 key value = Privacy - Photo Library Usage Description

Answer 4

斯威夫特3时，Xcode 9：我创建了一个扩展来实现这一点。希望这可以帮助你。

extension WKWebView{

     private func stageWebViewForScreenshot() {
        let _scrollView = self.scrollView
        let pageSize = _scrollView.contentSize;
        let currentOffset = _scrollView.contentOffset
        let horizontalLimit = CGFloat(ceil(pageSize.width/_scrollView.frame.size.width))
        let verticalLimit = CGFloat(ceil(pageSize.height/_scrollView.frame.size.height))

         for i in stride(from: 0, to: verticalLimit, by: 1.0) {
            for j in stride(from: 0, to: horizontalLimit, by: 1.0) {
                _scrollView.scrollRectToVisible(CGRect(x: _scrollView.frame.size.width * j, y: _scrollView.frame.size.height * i, width: _scrollView.frame.size.width, height: _scrollView.frame.size.height), animated: true)
                 RunLoop.main.run(until: Date.init(timeIntervalSinceNow: 1.0))
            }
        }
        _scrollView.setContentOffset(currentOffset, animated: false)
    }

     func fullLengthScreenshot(_ completionBlock: ((UIImage) -> Void)?) {
        // First stage the web view so that all resources are downloaded.
         stageWebViewForScreenshot()

        let _scrollView = self.scrollView

        // Save the current bounds
        let tmp = self.bounds
        let tmpFrame = self.frame
         let currentOffset = _scrollView.contentOffset

        // Leave main thread alone for some time to let WKWebview render its contents / run its JS to load stuffs.
         mainDispatchAfter(2.0) {
            // Re evaluate the size of the webview
            let pageSize = _scrollView.contentSize
             UIGraphicsBeginImageContext(pageSize)

            self.bounds = CGRect(x: self.bounds.origin.x, y: self.bounds.origin.y, width: pageSize.width, height: pageSize.height)
            self.frame = CGRect(x: self.frame.origin.x, y: self.frame.origin.y, width: pageSize.width, height: pageSize.height)

            // Wait few seconds until the resources are loaded
            RunLoop.main.run(until: Date.init(timeIntervalSinceNow: 0.5))

             self.layer.render(in: UIGraphicsGetCurrentContext()!)
            let image: UIImage = UIGraphicsGetImageFromCurrentImageContext()!
            UIGraphicsEndImageContext()

            // reset Frame of view to origin
            self.bounds = tmp
            self.frame = tmpFrame
            _scrollView.setContentOffset(currentOffset, animated: false)

             completionBlock?(image)
        }
    }
}

Answer 5

更新：不知道为什么贾森是坚持这样的回答都过网。它并没有解决如何截图全部WKWebView内容...包括了屏幕的问题。

尝试这个：

func snapshot() -> UIImage {
        UIGraphicsBeginImageContextWithOptions(self.webView.bounds.size, true, 0);
        self.webView.drawViewHierarchyInRect(self.webView.bounds, afterScreenUpdates: true);
        let snapshotImage = UIGraphicsGetImageFromCurrentImageContext();
        UIGraphicsEndImageContext();

        UIImageWriteToSavedPhotosAlbum(snapshotImage, nil, nil, nil)

        return snapshotImage
    }

图像将自动保存到的iOS相机胶卷（由UIImageWriteToSavedPhotosAlbum（））。