HTTP Async Downloader with Auto Resume on Error

Question

I have an asynchronous bootloader in my application, but sometimes the connection is lost, especially when I'm in a mobile connection, and if the file is large (> 10 MB). Is there a way to catch when the download stops, and then force it to resume with the completion of the download?

This is the doInBackground asynchronous task:

 protected String doInBackground(String... aurl) { int count; try { URL url = new URL(aurl[0]); URLConnection conexion = url.openConnection(); // conexion.setRequestProperty("Range", "bytes=" + downloaded + "-"); conexion.connect(); int lenghtOfFile = conexion.getContentLength(); pesoVideo = lenghtOfFile / 1048576; output = "/sdcard/" + folderString + "/" + nomeFile + ".mp3"; InputStream input = new BufferedInputStream(url.openStream()); OutputStream output = new FileOutputStream( VideoDownloaderBrowserActivity.this.output); byte data[] = new byte[1024]; long total = 0; while ((count = input.read(data)) != -1) { total += count; publishProgress("" + (int) ((total * 100) / lenghtOfFile)); output.write(data, 0, count); } output.flush(); output.close(); input.close(); } catch (Exception e) { } return null; } 

This is onProgressUpdate :

 protected void onProgressUpdate(String... progress) { if (Integer.parseInt(progress[0]) > progresso) { ... } } 

Answer 1

Here is a thread discussing renewable downloads in Android below API 9. Otherwise, DownloadManager is a good option for newer versions.

Basically, you need to include a byte that will be used on your server in order to allow resuming downloads.