在micromax funbook中打开pdf文件时文档为空（size 0kb）

Question

Iam试图从服务器下载pdf并在android micromax funbook中显示它。

我收到错误的文件大小为空（0 KB）。当打开PDF文件...

我是新到Android提示我我用的是什么编码是正确的或者不进行下载

public static void DownloadFile(String fileURL, File directory) { 
    try { 

        FileOutputStream f = new FileOutputStream(directory); 
        URL u = new URL(fileURL); 
        HttpURLConnection c = (HttpURLConnection) u.openConnection(); 
        c.setRequestMethod("GET"); 
        c.setDoOutput(true); 
        c.connect(); 
        InputStream in = c.getInputStream(); 
        byte[] buffer = new byte[1024]; 
        int len1 = 0; 
        while ((len1 = in.read(buffer)) > 0) { 
          f.write(buffer, 0, len1); 
        } 
        f.close(); 
      } catch (Exception e) { 
        e.printStackTrace(); 
      } 
    } 

和用于显示pdf的代码。

public void showPdf() { 
      File file = new File(Environment.getExternalStorageDirectory() 
        + "/pdf/Read.pdf"); 
      PackageManager packageManager = getPackageManager(); 
      Intent testIntent = new Intent(Intent.ACTION_VIEW); 
      testIntent.setType("application/pdf"); 
      List list = packageManager.queryIntentActivities(testIntent, 
        PackageManager.MATCH_DEFAULT_ONLY); 
      Intent intent = new Intent(); 
      intent.setAction(Intent.ACTION_VIEW); 
      Uri uri = Uri.fromFile(file); 
      intent.setDataAndType(uri, "application/pdf"); 
      startActivity(intent); 
     } 

Answer 1

使用DownloadManager而不是编写自己的下载代码。

Answer 2

您应该使用c.openStream();而不是c.getinputstream();。