Use a Handler inside an IntentService started by a BroadcastReceiver

Question

I want to use an IntentService (which is started from a BroadcastReceiver) to download a file from Internet, but I want to inform the user if the file was downloaded successfully or not and if was downloaded to parse the file. Using a handler and handleMessage inside my IntentService is a good solution? From what I read IntentServices is simple worker threads that expire after handling the intent, so is it possible that the handler does not handle the message ?

private void downloadResource(final String source, final File destination) {
    Thread fileDownload = new Thread(new Runnable() {
        @Override
        public void run() {
            try {
                URL url = new URL(source);
                HttpURLConnection urlConnection = (HttpURLConnection)
                                               url.openConnection();
                urlConnection.setRequestMethod("GET");
                urlConnection.setDoOutput(true);
                urlConnection.connect();

                FileOutputStream fileOutput = new FileOutputStream(destination);
                InputStream inputStream = urlConnection.getInputStream();

                byte[] buffer = new byte[1024];
                int bufferLength;

                while ((bufferLength = inputStream.read(buffer)) > 0) {
                    fileOutput.write(buffer, 0, bufferLength);
                }
                fileOutput.close();

                // parse the downloaded file ?
            } catch (Exception e) {
                e.printStackTrace();
                destination.delete();
            }
        }
    });
    fileDownload.start();
}

score 1 · Accepted Answer · edited May 23 '17 at 12:12

1

If you just want to create a notification to inform the user, then you can do it after download in your IntentService (see Sending a notification from a service in Android)

If you want to display a more elaborated UI (via an Activity) then you probably want to start one of your app's activities with startActivity() method (see android start activity from service)

If you don't need any UI stuff, just do the parsing in the IntentService right after download.

edited May 23 '17 at 12:12

Community

1
1

answered Sep 10 '12 at 11:41

sdabet

17,379
11
73
143

I simply want to parse the downloaded file, without any UI interaction. – Paul Sep 10 '12 at 11:43
Oh ok, but you said "I want to inform the user if the file was downloaded successfully or not". If you don't need any UI, why don't you parse it in your IntentService after download ? – sdabet Sep 10 '12 at 11:44
I added some code to the post. so it is ok to parse the file at line "// parse the downloaded file ?" ? – Paul Sep 10 '12 at 11:47
Sure. Why not? As long as your parsing does modify any UI stuff. – sdabet Sep 10 '12 at 11:58
I'll give it a try in few minutes. – Paul Sep 10 '12 at 12:01
But I don't see why you manually start a new thread...I assume that the `downloadResource()` method is called from your `IntentService` which already runs in a background thread. – sdabet Sep 10 '12 at 12:05

Use a Handler inside an IntentService started by a BroadcastReceiver

1 Answers1