打開並查看文檔文件URL

Question

如何使用QLPreviewController打開並查看從Web服務獲取的文檔文件的URL。

Answer 1

你不能這樣做。文檔可以很好地解釋這一點，但是，您想嘗試製作自己的查看器。祝你好運！

參見：

Oficial topic IOS

您可以作爲網站顯示：「創建和配置文檔交互控制器」

- (UIDocumentInteractionController *) setupControllerWithURL: (NSURL) fileURL 
usingDelegate: (id <UIDocumentInteractionControllerDelegate>) interactionDelegate { 

UIDocumentInteractionController *interactionController = 
    [UIDocumentInteractionController interactionControllerWithURL: fileURL]; 
interactionController.delegate = interactionDelegate; 

return interactionController;} 

「一旦你有一個文檔交互控制器，你可以使用其屬性獲取關於相關文件的信息，包括其名稱，類型和URL。「

Answer 2

1. 顯示某種進度微調。
2. 使用URLSession和URLSessionDownloadTask將文件下載到您的~/documents文件夾。
3. 隱藏進度微調器。
4. 然後，您需要創建一個實現QLPreviewControllerDataSource並保存文檔的類的實例。

5. 隱藏進度微調和現在QLPreviewController

   import UIKit 
   import QuickLook 
   
   
   class Document: NSObject, QLPreviewItem { 
       var previewItemURL: URL? 
   } 
   
   class PreviewDataSource: NSObject, QLPreviewControllerDataSource { 
   
       var document: Document? 
   
       func numberOfPreviewItems(in controller: QLPreviewController) -> Int { 
        return document != nil ? 1 : 0 
       } 
   
       func previewController(_ controller: QLPreviewController, previewItemAt index: Int) -> QLPreviewItem { 
        return document! 
       } 
   } 
   
   class ProgressLoadingViewController: UIViewController { 
   
       var session: URLSession = URLSession(configuration: URLSessionConfiguration.default) 
       var downloadTask: URLSessionDownloadTask? 
   
       var dataSource: PreviewDataSource? 
   
       override func viewDidLoad() { 
        super.viewDidLoad() 
        startDownload() 
       } 
   
       func startDownload() { 
        // start progres spinner 
        downloadTask = session.downloadTask(with: URL(string: "http://che.org.il/wp-content/uploads/2016/12/pdf-sample.pdf")!) { [weak self] (downloadLocation, response, error) in 
         guard // check if download went correctly 
          error != nil, 
          let filename = response?.suggestedFilename, 
          let downloadLocation = downloadLocation 
          else { 
           print("Something went wrong: \(error!)") 
           return 
         } 
   
         // copy file 
         let fileManager = FileManager.default 
         let targetPath = URL(fileURLWithPath: filename, relativeTo: fileManager.temporaryDirectory) 
         do { 
          try fileManager.copyItem(at: downloadLocation, to: targetPath) 
         } catch let fileError { 
          print("Copying failed: \(fileError)") 
          return 
         } 
   
         // prepare preview 
         let document = Document() 
         document.previewItemURL = targetPath 
         self?.dataSource? = PreviewDataSource() 
         self?.dataSource?.document = document 
   
         let qlViewController = QLPreviewController() 
         qlViewController.dataSource = self?.dataSource 
   
         // hide progress spinner 
         self?.present(qlViewController, animated: true) { 
          self?.downloadTask = nil 
          qlViewController.reloadData() 
         } 
        } 
        downloadTask?.resume() 
       } 
   } 
   

當然這漫長完成函數應該分成幾個，然後搬到了自己的類DocumentDownloadManager。