无法在使用 Alamofire 下载的 PDFView IOS 中查看 PDF - SWIFT

Posted 2023-03-12

【中文标题】无法在使用 Alamofire 下载的 PDFView IOS 中查看 PDF - SWIFT

【英文标题】：Cannot view PDF in PDFView IOS downloaded using Alamofire - SWIFT

【发布时间】：2018-03-18 00:17:47

【问题描述】：

我正在尝试从服务器下载 pdf 文件并将其显示在 ios 的 PDFView 中。我相信我已经成功下载（文件大小为 1.1Mb）并将其存储在 DocumentsDirectory 中。但是，当我尝试在 PDFView 中显示此 pdf 文件时，我看到一个空白的视图控制器。以下是我的代码：

我知道我的 UIView 对象已正确连接并正常工作。例如，如果我将“docURL”替换为以下文件 URL，我可以查看 PDF 文件：

 Bundle.main.url(forResource: "paper", withExtension: "pdf")

斯威夫特：

 let destination: DownloadRequest.DownloadFileDestination =  _, _ in
        let documentsURL = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)[0]
        let fileURL = documentsURL.appendingPathComponent("pig.pdf")

        return (fileURL, [.removePreviousFile, .createIntermediateDirectories])
    


    Alamofire.download(containerPDFUrl, to: destination).response  response in
        print("response downLoadPDFDocument: \(response)")

        if response.error == nil, let pdfFilePath = response.destinationURL?.path 

            print("inside DispatchQueue")
            print("pdfFilePath: \(pdfFilePath)")

            DispatchQueue.main.async
                // Instantiate PDFDocument
                let docURL = URL.init(string: pdfFilePath)
                let pdfDoc = PDFDocument.init(url: docURL!)
                self.myPDFView.document = pdfDoc

            
        else
            print("response.error : \(response.error )")
        
    

控制台：

 response downLoadPDFDocument: DefaultDownloadResponse(request: Optional(https://myLink/rab1Mpub.pdf), response: Optional(<NSHTTPURLResponse: 0x60c0000302a0>  URL: https://myLink/rab1Mpub.pdf   Status Code: 200, Headers 
"Accept-Ranges" =     (
    bytes
);
"Content-Length" =     (
    1113030
);
"Content-Type" =     (
    "application/octet-stream"
);
Date =     (
    "Sun, 18 Mar 2018 10:03:12 GMT"
);
Etag =     (
    "\"75b5f9132e45870cf1060c7ebfd0ed76\""
);
"Last-Modified" =     (
    "Mon, 12 Mar 2018 18:42:05 GMT"
);
Server =     (
    AmazonS3
);
"x-amz-id-2" =     (
    "KpynA2h+IMZKEk3ErsAAeIuvWOcuqBQMNiiwBV2K4j42TfC5z/ZQihvZFuHb7rHq0ESeKKeeD+s="
);
"x-amz-request-id" =     (
    F88529EC82881CD2
);
 ), temporaryURL: Optional(file:///Users/myName/Library/Developer/CoreSimulator/Devices/7EBBAD08-6C66-4108-AB24-DEA8892E207A/data/Containers/Data/Application/6BBA1B08-9F77-4509-952C-7F7528DAE855/tmp/CFNetworkDownload_h2MGIC.tmp), destinationURL: Optional(file:///Users/myName/Library/Developer/CoreSimulator/Devices/7EBBAD08-6C66-4108-AB24-DEA8892E207A/data/Containers/Data/Application/6BBA1B08-9F77-4509-952C-7F7528DAE855/Documents/pig.pdf), resumeData: nil, error: nil, timeline: Timeline:  "Request Start Time": 543060190.971, "Initial Response Time": 543060192.280, "Request Completed Time": 543060201.253, "Serialization Completed Time": 543060201.253, "Latency": 1.309 secs, "Request Duration": 10.281 secs, "Serialization Duration": 0.000 secs, "Total Duration": 10.281 secs , _metrics: Optional((Task Interval) <_NSConcreteDateInterval: 0x608000227b00> (Start Date) 2018-03-18 10:03:10 +0000 + (Duration) 10.203282 seconds = (End Date) 2018-03-18 10:03:21 +0000
(Redirect Count) 0
(Transaction Metrics) (Request) <NSURLRequest: 0x608000008110>  URL: https://myLink/rab1Mpub.pdf 
(Response) <NSHTTPURLResponse: 0x608000227700>  URL: https://myLink/rab1Mpub.pdf   Status Code: 200, Headers 
"Accept-Ranges" =     (
    bytes
);
"Content-Length" =     (
    1113030
);
"Content-Type" =     (
    "application/octet-stream"
);
Date =     (
    "Sun, 18 Mar 2018 10:03:12 GMT"
);
Etag =     (
    "\"75b5f9132e45870cf1060c7ebfd0ed76\""
);
"Last-Modified" =     (
    "Mon, 12 Mar 2018 18:42:05 GMT"
);
Server =     (
    AmazonS3
);
"x-amz-id-2" =     (
    "KpynA2h+IMZKEk3ErsAAeIuvWOcuqBQMNiiwBV2K4j42TfC5z/ZQihvZFuHb7rHq0ESeKKeeD+s="
);
"x-amz-request-id" =     (
    F88529EC82881CD2
);
 
(Fetch Start) 2018-03-18 10:03:10 +0000
(Domain Lookup Start) 2018-03-18 10:03:10 +0000
(Domain Lookup End) 2018-03-18 10:03:11 +0000
(Connect Start) 2018-03-18 10:03:11 +0000
(Secure Connection Start) 2018-03-18 10:03:11 +0000
(Secure Connection End) 2018-03-18 10:03:11 +0000
(Connect End) 2018-03-18 10:03:11 +0000
(Request Start) 2018-03-18 10:03:11 +0000
(Request End) 2018-03-18 10:03:11 +0000
(Response Start) 2018-03-18 10:03:11 +0000
(Response End) 2018-03-18 10:03:21 +0000
(Protocol Name) http/1.1
(Proxy Connection) NO
(Reused Connection) NO
(Fetch Type) Network Load

))
inside DispatchQueue
pdfFilePath: 
/Users/myName/Library/Developer/CoreSimulator/Devices/7EBBAD08-6C66-4108-AB24-DEA8892E207A/data/Containers/Data/Application/6BBA1B08-9F77-4509-952C-7F7528DAE855/Documents/pig.pdf
2018-03-18 10:03:27.341067+0000 labbook[38709:4229832] [BoringSSL] Function boringssl_session_errorlog: line 2871 [boringssl_session_read] SSL_ERROR_ZERO_RETURN(6): operation failed because the connection was cleanly shut down with a close_notify alert
2018-03-18 10:04:06.253109+0000 labbook[38709:4231789] TIC Read Status [1:0x608000167800]: 1:57
2018-03-18 10:04:06.253340+0000 labbook[38709:4231789] TIC Read Status [1:0x608000167800]: 1:57
2018-03-18 10:04:06.253512+0000 labbook[38709:4231789] TIC Read Status [1:0x608000167800]: 1:57

【参考方案1】：

PDFDocument(url: URL) 只接受文件URL，但在你的代码中你说：

let fileURL = URL.init(string: self.containerPDFUrl)
let pdfDoc = PDFDocument.init(url: fileURL!)

你说self.containerPDFUrl是那种类型

https://example.org/rab1Mpub.pdf

但这不是文件网址。我相信你是有意的：

let pdfDoc = PDFDocument(url: self.destination.0)

但是let fileURL = documentsURL.appendingPathComponent("pig.png") 应该是let fileURL = documentsURL.appendingPathComponent("pig.pdf")

更新

if response.error == nil, let pdfFilePath = response.destinationURL?.path 

        print("inside DispatchQueue")
        print("pdfFilePath: \(pdfFilePath)")

        DispatchQueue.main.async
            // Instantiate PDFDocument
            let docURL = URL.init(string: pdfFilePath)
            let pdfDoc = PDFDocument.init(url: docURL!)
            self.myPDFView.document = pdfDoc

        
 

这里不需要处理路径。只需获取destinationURL 并从中初始化文档。例如：

if response.error == nil, let pdfURL = response.destinationURL? 

        DispatchQueue.main.async
            // Instantiate PDFDocument
            let pdfDoc = PDFDocument(url: pdfURL)
            self.myPDFView.document = pdfDoc

        

【讨论】：

我已经更正了我的代码（参见上面的编辑），但我仍然看到一个空白的 viewController。我还更新了控制台中的当前信息。

/Users/myName/Library/Developer/CoreSimulator/Devices/7EBBAD08-6C66-4108-AB24-DEA8892E207A/data/Containers/Data/Application/6BBA1B08-9F77-4509-952C-7F7528DAE855/Documents/pig.pdf 不是有效的文件 url，因为没有应该是 file:// 的方案，请参阅我的更新答案