how to repeat an alarm android?

Question

How to repeat an alarm manager to run my activity once in 30 minutes? How to simply run this main activity once in 30 minutes can anybody explain me pls

code :

import android.app.Activity;
import android.os.Bundle;

public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

    }

}

Answer 1

private void setLocationSendingAlarm() {

    AlarmManager alarmManager = (AlarmManager) getApplicationContext().getSystemService(Context.ALARM_SERVICE);
    Intent intent = new Intent(getApplicationContext(), GoogleMapService.class);
    intent.putExtra("locationSendingAlarm", true);
    PendingIntent   pendingIntent = PendingIntent.getService(this, 987654321, intent,0);
    try {
        alarmManager.cancel(pendingIntent);
    } catch (Exception e) {

    }
    int timeForAlarm=60000;


    alarmManager.setRepeating(AlarmManager.RTC_WAKEUP, System.currentTimeMillis()+50000, timeForAlarm, pendingIntent);
}