ios - UIDocumentInteractionController 不起作用

Question

在我的应用程序中，我下载各种格式的文件。我试图让 UIDocumentInteractionController 获得可以打开这种格式的应用程序。问题是 UIDocumentInteractionController 不工作。这是我的代码:

func loadArchiveAtIndex(sender: NSNotification){
        let itemIndex = sender.userInfo!["index"] as! Int
        let archiveKey = sender.userInfo!["downloadKey"] as! String

        self.downloadingItens.append(itemIndex)
        print(archiveKey)

        let qualityOfServiceClass = QOS_CLASS_BACKGROUND
        let backgroundQueue = dispatch_get_global_queue(qualityOfServiceClass, 0)
        dispatch_async(backgroundQueue, {

            SQLiteDataController().getTokenSincronismo({
                (Valido, Retorno, Token, Tipo) -> Void in
                if Valido == true{
                    switch Retorno {
                    case 9: // Retorno Válido
                        print(Token)

                        let params = [
                            "tokenSincronizacao":"\(Token)",
                            "chaveProdutoBiblioteca":"\(archiveKey)"
                        ]
                        Alamofire.request(.GET, "\(_URLPREFIX)/ObtemProdutoBiblioteca", parameters: params).responseJSON { (response) in
                            if response.result.isFailure {
                                print(response.result.error)
                            } else {
                                let result = response.result.value
                                if let archive = result?["ProdutoBiblioteca"] as? NSDictionary{
                                    let bytes = archive.objectForKey("Arquivo") as! String
                                    let name = archive.objectForKey("NomeArquivo") as! String
                                    let data = NSData.init(base64EncodedString: bytes, options: .IgnoreUnknownCharacters)
                                    let url = NSURL.init(string: name.lowercaseString)
                                    data?.writeToURL(url!, atomically: true)

                                    let documents = try! NSFileManager.defaultManager().URLForDirectory(.DocumentDirectory, inDomain: .UserDomainMask, appropriateForURL: nil, create: false)
                                    let fileURL = documents.URLByAppendingPathComponent((name.lowercaseString))
                                    print(fileURL)

                                    let dic = UIDocumentInteractionController.init(URL: fileURL!)
                                    dic.delegate = self
                                    dic.presentPreviewAnimated(true)
//
                                    dispatch_async(dispatch_get_main_queue(), { () -> Void in
                                        var arrayIndex = 0
                                        for item in self.downloadingItens {
                                            let i = item
                                            if i == itemIndex {
                                                self.downloadingItens.removeAtIndex(arrayIndex)
                                                NSNotificationCenter.defaultCenter().postNotificationName("reloadTable", object: nil, userInfo: ["itens":self.downloadingItens])
                                                break
                                            }
                                            arrayIndex = arrayIndex + 1
                                        }
                                    })

                                }
                            }
                        }

                        break
                    default:
                        self.showError("Atenção", message: "Não foi Possivel Processar a sua Solicitação")
                        break
                    }
                }else{
                    self.showError("Atenção", message: "Não foi Possivel Processar a sua Solicitação")
                }
                }, sincFull:true)
        })
    }

    func documentInteractionControllerViewForPreview(controller: UIDocumentInteractionController) -> UIView? {
            return self.view
        }

我做错了什么？

Answer 1

您需要从主线程呈现 View 。

代替:

let dic = UIDocumentInteractionController.init(URL: fileURL!)
dic.delegate = self
dic.presentPreviewAnimated(true)

尝试:

dispatch_async(dispatch_get_main_queue(), { () -> Void in
   let dic = UIDocumentInteractionController.init(URL: fileURL!)
   dic.delegate = self
   dic.presentPreviewAnimated(true)                                    
})