在 iOS 10 上的 WKWebView 中打開 PDF 文件時啟用雙指縮放手勢

Question

我正在尋找一種在 iOS 10 上的 WKWebview 中打開本地 PDF 文件時啟用“捏合縮放”放大手勢的方法。據我所知，在 iOS 12 上啟用了捏合縮放

class ViewController: UIViewController {
   var wkWebView: WKWebView?
   @IBOutlet var webView: UIView!
   fileprivate var delegate = AuthenticatedWebViewNavigationDelegate()

   override func viewDidLoad() {
     super.viewDidLoad()

     if wkWebView == nil {
        createWebView()
     }
     let filePath = Bundle.main.path(forResource: "local", ofType: 
      "pdf")
     let baseUrl = URL(fileURLWithPath: filePath!)
     wkWebView?.loadFileURL(baseUrl, allowingReadAccessTo: baseUrl)

   }
}

class AuthenticatedWebViewNavigationDelegate: NSObject, WKNavigationDelegate {
    weak var viewController: ViewController?

    public func webView(_ webView: WKWebView, decidePolicyFor navigationAction: WKNavigationAction, decisionHandler: @escaping (WKNavigationActionPolicy) -> Void) {
            decisionHandler(.allow)
       }

    public func webView(_ webView: WKWebView, decidePolicyFor navigationResponse: WKNavigationResponse, decisionHandler: @escaping (WKNavigationResponsePolicy) -> Void) {
            decisionHandler(.allow)
       }

    public func webView(_ webView: WKWebView, didFailProvisionalNavigation navigation: WKNavigation!, withError error: Error) { 
            print("error")
       }

    public func webView(_ webView: WKWebView, didFinish navigation: WKNavigation!) {
            print("finish")
       }
    public func webView(_ webView: WKWebView, didFail navigation: WKNavigation!, withError error: Error) {
           print("error")
       }
}

Answer 1

我發現在 iOS 10 的 wkwebview 上禁用了 scrollview.pinchGestureRecognizer

所以解決辦法是啟用pinchGestureRecognizer，我把這個函數放在下面的函數中：

public func webView(_ webView: WKWebView, didFinish navigation: WKNavigation!) {
    if #available(iOS 11.0, *) {
    } else {
      if webView.url?.scheme == "file" {                       
         webView.scrollView.pinchGestureRecognizer?.isEnabled = true
       }
    }

        print("finish")
   }