Question

I have a android Service, in the onStart method i get many Strings from the Intent activity, and then execute a AsynTask to download files from internet.

When the activity is running this works ok, but when i stop the activity, this relaunch the onStart method, but obiusly the intent is null causing me nullPointerException.

What can i do the service dont entry on onStart, and continues the first asyntask to download all the files?

This is my code

    @Override
    public void onStart(Intent intent, int startId) {
        desde = intent.getIntExtra("desde", 0);
        hasta = intent.getIntExtra("hasta", 1);
        email = intent.getStringExtra("email");
        password = intent.getStringExtra("password");

        new DescargaFotos().execute();

    }

@Override
    public IBinder onBind(Intent intent) {

        return null;
    }

and in Inicio.java (The UI activity)

Intent iService = new Intent(contexto,


    ServiceDownloader.class);
                            iService.putExtra("desde", 0);
                            iService.putExtra("hasta", 5);
                            iService.putExtra("email", email);
                            iService.putExtra("password", password);
                            startService(iService);     

EDIT:

New question:

I am using IntentService and i bind the service like this:

Intent iService = new Intent(contexto,
                                ServiceDownloader.class);

                        ServiceConnection serviceConector = new ServiceConnection() {

                            @Override
                            public void onServiceDisconnected(ComponentName name) {
                                Log.i("INFO", "Service bound ");
                            }

                            @Override
                            public void onServiceConnected(ComponentName name,
                                    IBinder service) {
                                Log.i("INFO", "Service Unbound ");
                            }
                        };

                        iService.putExtra("desde", 0);
                        iService.putExtra("hasta", 50);
                        iService.putExtra("email", email);
                        iService.putExtra("password", password);
                        startService(iService);
                        bindService(iService, serviceConector,
                                Context.BIND_AUTO_CREATE);

And now my problem is, in my galaxy nexus, if i enter in app runtime list, and destroy my app, the service stopped, and stop donwload, stop send notification etc? How must i bind the service to solve this?

Answer 1

Use an IntentService. IntentService is specifically designed to do what you want. You don’t have to implement onStart, onStartCommand, etc. The work runs on a background thread. Once the work finishes, the Thread is destroyed.

IntentService will continue to run regardless of the state of the Activity.

One problem you may have is that you’re sending out your Intent in the wrong place in your Activity, or you’re not checking to see if the operation is complete. Before you send the Intent, check a flag in SharedPreferences (if the flag doesn’t exist, it means you’re starting for the first time). When you send the Intent, store a flag in SharedPreferences to indicate that you sent it. When your IntentService receives the Intent, have it update the flag to say it received it. Before the IntentService finishes, have it update the flag again. And so forth.