Setting up a background process with Threading to handle work in Android

Question

Hello I am trying to create a sample app when executed, will bring you back to the home screen , run a back ground process, and display toast points.

I figure that I will need a separate thread in the background process to do whatever work I need. Here is the Code of my Main Activity(BackGroundPrcessingExampleActivity):

enter code here
public class BackGroundProcessExampleActivity extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        try {

            Intent myIntent = new Intent(this, MyService.class);
            startService(myIntent);

            moveTaskToBack(false);

        } catch (Exception e) {
            e.printStackTrace();
        }
    }

Here is the Code from "MyService.java":

enter code here
public int onStartCommand(Intent intent, int flags, int startId) {

    Toast.makeText(getBaseContext(), "Service is started!", 1).show();

    myHandler = new Handler() {

        @Override
        public void handleMessage(Message msg) {

            super.handleMessage(msg);


                Toast.makeText(getBaseContext(), "Hello!",
                        Toast.LENGTH_SHORT).show();
        }
    };



    Runnable runnable = new Runnable() {
        @Override
        public void run() {



            while (true) {

                try {               

                    Thread.sleep(2);

                    myHandler.sendEmptyMessage(0);

                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        }
    };
    new Thread(runnable).start();

    return super.onStartCommand(intent, flags, startId);
}

The problem I am having is that the Toast message is not appearing. I can put breakpoints and see that it is stepping through the code but no message appears. I think it might be that the context is not correct? Do I need the UI's Context(BackGroundPRcessExampleActivity)? Any help is appreciated, thanks in advance.

D

Answer 1

With the help of the replies, this is what eventually worked for me. There is notification code added.

    @Override
public int onStartCommand(Intent intent, int flags, int startId) {

    final NotificationManager notificationManager = (NotificationManager) 
            getSystemService(NOTIFICATION_SERVICE);

    // Create Notifcation
    final Notification notification = new Notification(R.drawable.ic_launcher,
        "A new notification", System.currentTimeMillis());

    // Cancel the notification after its selected
    notification.flags |= Notification.FLAG_AUTO_CANCEL;
    //
    notification.number += 1;

    // Specify the called Activity
    Intent intent2 = new Intent(this, NotificationReceiver.class);

    Toast.makeText(getApplicationContext(), "Service is started!", 1)
            .show();

    PendingIntent activity = PendingIntent.getActivity(this, 0, intent2, 0);
    notification.setLatestEventInfo(this, "This is the title",
        "This is the text", activity);


    myHandler = new Handler();

    Runnable runnable = new Runnable() {
        @Override
        public void run() {
            int i = 0;

            while (true) {
                final int x = i++;

                try {
                    Thread.sleep(500);
                } catch (InterruptedException e1) {
                    e1.printStackTrace();
                }

                myHandler.post(new Runnable() {

                    @Override
                    public void run() {

                        try {
                            Toast.makeText(getApplicationContext(),
                                    "Hello!" + String.valueOf(x),
                                    3).show();

                            if(x == 100)
                                notificationManager.notify(0, notification);
                            Thread.sleep(1);

                        } catch (InterruptedException e) {
                            e.printStackTrace();
                        }
                    }
                });
            }
        }
    };
    new Thread(runnable).start();

Thank you everyone for their help.

D