我正在为一个安卓应用程序开发一个 webview，该 webview 指向另一个团队创建的动态网站。
当我下载文件（主要是动态重定向的 PDF 和 ZIP 文件）时，我得到的只是一个包含一些 HTML 代码的下载文件夹中的文件，并显示“用户不允许读取文件”信息。，无论我如何实现下载，我尝试过：
- DownloadManager
- Intent（让外部浏览器来管理下载）
- 手动下载（AsyncTask 和 httpconnection...）
所有方法都得到相同结果。
在普通浏览器中导航下载很好用，包括台式电脑，安卓和 iOS 设备。
为什么 WebView 不能访问文件？
可能是会话问题？http 端口？
我真的需要一些想法...
另一个提示：当从相同链接下载两次文件时，链接将重定向到相同的文件，但会产生两个不同的文件名...
编辑：我尝试将 webView 指向一个常规网页，该网页通过链接重定向以下载其他文件，嗯，简单地说它起作用了。
这里是 webview.setDownloadListener - onDownloadStart() 参数：
userAgent=Mozilla/5.0 (Linux; Android 4.4.2; Nexus 7 Build/KOT49H) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/30.0.0.0 Safari/537.36
contentDisposition=attachment;
filename=correct_filename.pdf,
url=http://www.xxx.xx/site/downloadfile.wplus?REDIRECTFILE=D-507497120&ID_COUNTOBJ=ce_5_home&TYPEOBJ=CExFILE&LN=2
mimeType=application/octet-stream
这里是一些代码
wv.getSettings().setSupportMultipleWindows(true);
wv.getSettings().setJavaScriptCanOpenWindowsAutomatically(true);
wv.getSettings().setAllowFileAccess(true);
wv.getSettings().setJavaScriptEnabled(true);
wv.getSettings().setBuiltInZoomControls(true);
wv.getSettings().setDisplayZoomControls(false);
wv.getSettings().setLoadWithOverviewMode(true);
wv.getSettings().setUseWideViewPort(true);
wv.setDownloadListener(new DownloadListener() {
@Override
public void onDownloadStart(String url, String userAgent, String contentDisposition, String mimetype, long contentLength){
DownloadManager.Request request = new DownloadManager.Request(Uri.parse(url));
request.setDescription("Download file...");
request.setTitle(URLUtil.guessFileName(url, contentDisposition, mimetype));
request.allowScanningByMediaScanner();
request.setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED); //Notify client once download is completed!
request.setDestinationInExternalPublicDir(Environment.DIRECTORY_DOWNLOADS, URLUtil.guessFileName(url, contentDisposition, mimetype));
DownloadManager dm = (DownloadManager) getSystemService(DOWNLOAD_SERVICE);
dm.enqueue(request);
Toast.makeText(getApplicationContext(), "Downloading File", Toast.LENGTH_LONG).show();
}
}
编辑 II
这是我在手动下载文件时使用的代码：
在 onDownloadStart() 中调用 downloadFileAsync()：
public void onDownloadStart(String url, String userAgent, String contentDisposition, String mimeType, long contentLength) {
String fileName;
try {
fileName = URLUtil.guessFileName(url, contentDisposition, mimeType);
downloadFileAsync(url, fileName);
}catch (Exception e){
}
}
这是异步任务（AsyncTask）：
private void downloadFileAsync(String url, String filename){
new AsyncTask<String, Void, String>() {
String SDCard;
@Override
protected void onPreExecute() {
super.onPreExecute();
}
@Override
protected String doInBackground(String... params) {
try {
URL url = new URL(params[0]);
HttpURLConnection urlConnection = null;
urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.setDoOutput(true);
urlConnection.connect();
int lengthOfFile = urlConnection.getContentLength();
//SDCard = Environment.getExternalStorageDirectory() + File.separator + "downloads";
SDCard = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS)+"";
int k = 0;
boolean file_exists;
String finalValue = params[1];
do {
if (k > 0) {
if (params[1].length() > 0) {
String s = params[1].substring(0, params[1].lastIndexOf("."));
String extension = params[1].replace(s, "");
finalValue = s + "(" + k + ")" + extension;
} else {
String fileName = params[0].substring(params[0].lastIndexOf('/') + 1);
String s = fileName.substring(0, fileName.lastIndexOf("."));
String extension = fileName.replace(s, "");
finalValue = s + "(" + k + ")" + extension;
}
}
File fileIn = new File(SDCard, finalValue);
file_exists = fileIn.exists();
k++;
} while (file_exists);
File file = new File(SDCard, finalValue);
FileOutputStream fileOutput = null;
fileOutput = new FileOutputStream(file, true);
InputStream inputStream = null;
inputStream = urlConnection.getInputStream();
byte[] buffer = new byte[1024];
int count;
long total = 0;
while ((count = inputStream.read(buffer)) != -1) {
total += count;
//publishProgress(""+(int)((total*100)/lengthOfFile));
fileOutput.write(buffer, 0, count);
}
fileOutput.flush();
fileOutput.close();
inputStream.close();
} catch (MalformedURLException e){
} catch (ProtocolException e){
} catch (FileNotFoundException e){
} catch (IOException e){
} catch (Exception e){
}
return params[1];
}
@Override
protected void onPostExecute(final String result) {
}
}.execute(url, filename);
}
do you know already which headers you have to add?- greenapps