android timer handler

Question

i am using this code public class newtimer extends Activity {

    private Timer myTimer;

@Override

public void onCreate(Bundle icicle) {
    super.onCreate(icicle);
    setContentView(R.layout.main);

    myTimer = new Timer();
    myTimer.schedule(new TimerTask() {
        @Override
        public void run() {
            TimerMethod();
        }

    }, 0, 1000);
}

int number = 0;

private void TimerMethod()
{
    //This method is called directly by the timer
    //and runs in the same thread as the timer.

    //We call the method that will work with the UI
    //through the runOnUiThread method.

    Toast.makeText(this, "TimerMethod Running "+number, Toast.LENGTH_SHORT).show();

    this.runOnUiThread(Timer_Tick);
}

private Runnable Timer_Tick = new Runnable() {
    public void run() {

    //This method runs in the same thread as the UI.               
    //Do something to the UI thread here

        Toast.makeText(getBaseContext(), "UI Thread Running "+number, Toast.LENGTH_SHORT).show();

    }
};
}

when i run it i get this exception in logcat

09-06 21:39:39.701: ERROR/AndroidRuntime(1433): java.lang.RuntimeException: Can't create handler inside thread that has not called Looper.prepare()

what do i do ? i kno its something with handlers but i need help with the code... :/ Thank you

Answer 1

I would assume the problem is with the Toast.makeText(this, "TimerMethod Running "+number, Toast.LENGTH_SHORT).show(); in your TimerMethod function - you can't call any functions pertaining to the UI from worker threads. Since you already have a Toast in the portion that runs in the UI thread, why do you have another one in TimerMethod?

For debugging, I would recommend using Log as much as possible instead of Toast.