Android run thread in service every X seconds

Question

I want to create a thread in an Android service that runs every X seconds

I am currently using , but the postdelayed method seems to really lag out my app.

Answer 1

There are number of alternative ways to do this. Personally, I prefer to use ScheduledExecutorService:

ScheduledExecutorService scheduleTaskExecutor = Executors.newScheduledThreadPool(5);

// This schedule a runnable task every 2 minutes
scheduleTaskExecutor.scheduleAtFixedRate(new Runnable() {
  public void run() {
    doSomethingUseful();
  }
}, 0, 2, TimeUnit.MINUTES);

Answer 2

Starting a runnable every few seconds is gonna have some lag no matter what way you slice it, no? I don't see why a Handler shouldn't work just fine.

You might be experiencing some troubles though because you have

void startRepeatingTask()
{
    m_handlerTask.run(); 
}

Instead, you should use the Handler and do something like:

void startRepeatingTask()
{
    m_handler.post(m_handlerTask); 
}

(As an aside, the convention in Java is to use camel case, not snake case. So it should be mHandler, not m_handler, etc. Just telling you because it might make your code easier to read for some.)

Answer 3

Here is how I run a repeating thread, as you'll see it loops every 1 second. I see no lag with this method.

final Thread t = new Thread(new RepeatingThread());
t.start();

And the class:

import android.os.Handler;

public class RepeatingThread implements Runnable {

    private final Handler mHandler = new Handler();

    public RepeatingThread() {

    }

    @Override
    public void run() { 
        mHandler.postDelayed(this, 1000);       
    }
}

Answer 4

MyService.java

public class MyService extends Service {

    public static final int notify = 5000;  //interval between two services(Here Service run every 5 seconds)
    int count = 0;  //number of times service is display
    private Handler mHandler = new Handler();   //run on another Thread to avoid crash
    private Timer mTimer = null;    //timer handling

    @Override
    public IBinder onBind(Intent intent) {
        throw new UnsupportedOperationException("Not yet implemented");
    }

    @Override
    public void onCreate() {
        if (mTimer != null) // Cancel if already existed
            mTimer.cancel();
        else
            mTimer = new Timer();   //recreate new
        mTimer.scheduleAtFixedRate(new TimeDisplay(), 0, notify);   //Schedule task
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        mTimer.cancel();    //For Cancel Timer
        Toast.makeText(this, "Service is Destroyed", Toast.LENGTH_SHORT).show();
    }

    //class TimeDisplay for handling task
    class TimeDisplay extends TimerTask {
        @Override
        public void run() {
            // run on another thread
            mHandler.post(new Runnable() {
                @Override
                public void run() {
                    // display toast
                    Toast.makeText(MyService.this, "Service is running", Toast.LENGTH_SHORT).show();
                }
            });

        }

    }
}

MainActivity.java

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        startService(new Intent(this, MyService.class)); //start service which is MyService.java
    }
}

Add following code in AndroidManifest.xml

AndroidManifest.xml

<service android:name=".MyService" android:enabled="true" android:exported="true"></service>