当使用 swift3.0 执行按钮操作时，如何在 ios 移动设备中打开文档文件，例如（.pdf、.doc、.docx）？

我需要打开UIDocumentPickerViewController它应该允许用户选择所有类型的文件。即我使用的(.pdf,.doc)文件UIDocumentPickerViewController方法。 我的代码：

UIDocumentPickerDelegate, UIDocumentMenuDelegate在我的班级宣言中

//上传文件

func OpenFile(){

    let importMenu = UIDocumentMenuViewController(documentTypes: [String(kUTTypePNG),String(kUTTypeImage)], in: .import)
    importMenu.delegate = self
    importMenu.modalPresentationStyle = .fullScreen
    self.present(importMenu, animated: true, completion: nil)

}
@available(iOS 8.0, *)
public func documentPicker(_ controller: UIDocumentPickerViewController, didPickDocumentAt url: URL) {        
    let cico = url as URL
    print("The Url is : \(cico)")

    do {
        let weatherData = try NSData(contentsOf: cico, options: NSData.ReadingOptions())
        print(weatherData)
        let activityItems = [weatherData]
        let activityController = UIActivityViewController(activityItems: activityItems, applicationActivities: nil)
        if UI_USER_INTERFACE_IDIOM() == .phone {
            self.present(activityController, animated: true, completion: { _ in })
        }
        else {
            let popup = UIPopoverController(contentViewController: activityController)
            popup.present(from: CGRect(x: CGFloat(self.view.frame.size.width / 2), y: CGFloat(self.view.frame.size.height / 4), width: CGFloat(0), height: CGFloat(0)), in: self.view, permittedArrowDirections: .any, animated: true)
        }

    } catch {
        print(error)
    }

    //optional, case PDF -> render
    //displayPDFweb.loadRequest(NSURLRequest(url: cico) as URLRequest)      


}

@available(iOS 8.0, *)
public func documentMenu(_ documentMenu:     UIDocumentMenuViewController, didPickDocumentPicker documentPicker: UIDocumentPickerViewController) {

    documentPicker.delegate = self
    present(documentPicker, animated: true, completion: nil)        
} 


func documentPickerWasCancelled(_ controller: UIDocumentPickerViewController) {

    print(" cancelled by user")

    dismiss(animated: true, completion: nil)        

}

在此代码中，应用程序将崩溃。原因是Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'You cannot initialize a UIDocumentPickerViewController except by the initWithDocumentTypes:inMode: and initWithURL:inMode: initializers.

我不知道如何初始化initWithDocumentTypes:inMode.我是 iOS 新手，有人可以帮助我吗？？？ 你能帮我么..

斯威夫特 3*, 4*,

要打开文档并选择任何文档，您正在使用UIDocumentPickerViewController如果用户设备中连接了 Google Drive，则将显示 iCloud、文件和 Google Drive 中显示的所有文档。然后选定的文档需要在您的应用程序中下载，然后您可以在其中显示它WKWebView,

   @IBAction func uploadNewResumeAction(_ sender: Any) {

  /*  let documentPicker = UIDocumentPickerViewController(documentTypes: ["com.apple.iwork.pages.pages", "com.apple.iwork.numbers.numbers", "com.apple.iwork.keynote.key","public.image", "com.apple.application", "public.item","public.data", "public.content", "public.audiovisual-content", "public.movie", "public.audiovisual-content", "public.video", "public.audio", "public.text", "public.data", "public.zip-archive", "com.pkware.zip-archive", "public.composite-content", "public.text"], in: .import) */

    let documentPicker = UIDocumentPickerViewController(documentTypes: ["public.text", "com.apple.iwork.pages.pages", "public.data"], in: .import)

    documentPicker.delegate = self
    present(documentPicker, animated: true, completion: nil)
}

   extension YourViewController: UIDocumentPickerDelegate{


      func documentPicker(_ controller: UIDocumentPickerViewController, didPickDocumentAt url: URL) {

                let cico = url as URL
                print(cico)
                print(url)

                print(url.lastPathComponent)

                print(url.pathExtension)

               }
   }

注意：如果您打算选择所有文件，则必须使用以下代码：

  let documentPicker = UIDocumentPickerViewController(documentTypes: ["com.apple.iwork.pages.pages", "com.apple.iwork.numbers.numbers", "com.apple.iwork.keynote.key","public.image", "com.apple.application", "public.item","public.data", "public.content", "public.audiovisual-content", "public.movie", "public.audiovisual-content", "public.video", "public.audio", "public.text", "public.data", "public.zip-archive", "com.pkware.zip-archive", "public.composite-content", "public.text"], in: .import) 

在你的行动方法中。