setRepeating() of AlarmManager repeats after 1 min

Question

I have set the repeat time to 5 seconds. The first toast appears after 5 seconds, but all the next once repeat after 1 minute.
I tried the code with setRepeating() as well, it still doesn't work.
here is my code:

public void constructJob(){

    Intent alertIntent = new Intent(this, AlarmManagerService.class);
    PendingIntent pendingIntent = PendingIntent.getBroadcast(
            this, 0,
            alertIntent,
            PendingIntent.FLAG_UPDATE_CURRENT);

    AlarmManager alarmManager = (AlarmManager)getSystemService(Context.ALARM_SERVICE);
    alarmManager.setInexactRepeating(
            AlarmManager.RTC_WAKEUP,
            GregorianCalendar.getInstance().getTimeInMillis(),
            repeatTime(),
            pendingIntent
    );

}

public long repeatTime(){
    return 5000;
}

AlarmManagerService.java

public class AlarmManagerService extends BroadcastReceiver {
      @Override
      public void onReceive(Context context, Intent intent) {
             Toast.makeText(context, "5 seconds have passed",
                            Toast.LENGTH_SHORT).show();
}

Answer 1

Don't use setRepeating() or setInExactRepeating, it won't repeat after exactly 5 seconds. Instead, try scheduling the alarm once, then reschedule it again in the onReceive() method something like this. This will repeat after a particular time interval (5 seconds in this case)

MainActivity.java

public class MainActivity extends AppCompatActivity {

Button btnStartAlarm, btnStopAlarm;

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

    btnStartAlarm = (Button) findViewById(R.id.btnStartAlarm);
    btnStopAlarm = (Button) findViewById(R.id.btnStopAlarm);

    Intent intent = new Intent(MainActivity.this, AlarmReceiver.class);
    final PendingIntent pendingIntent = PendingIntent.getBroadcast(getApplicationContext(), 100, intent, 0);

    final AlarmManager alarmManager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);

    btnStartAlarm.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            alarmManager.set(AlarmManager.RTC_WAKEUP, System.currentTimeMillis() + 5000, pendingIntent);
        }
    });

    btnStopAlarm.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            alarmManager.cancel(pendingIntent);
        }
    });
}
 }

AlarmReceiver.java

public class AlarmReceiver extends BroadcastReceiver {
public AlarmReceiver() {
}

@Override
public void onReceive(Context context, Intent intent) {

    Log.d("Javed", "onReceive called");
    Toast.makeText(context, "onReceive called", Toast.LENGTH_LONG).show();

    Intent intent1 = new Intent(context, AlarmReceiver.class);
    final PendingIntent pendingIntent = PendingIntent.getBroadcast(context, 100, intent1, 0);
    final AlarmManager alarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
    alarmManager.set(AlarmManager.RTC_WAKEUP, System.currentTimeMillis() + 5000, pendingIntent);
}
  }

Answer 2

The documentation needs to be updated. As of I think Android 5.1 (API version 22) there is a minimum period of 1 minute for repeating alarms, and alarms cannot be set less than 5 seconds in the future.

If you need to do work within one minute, just set the alarm directly, then set the next one from that alarm's handler, etc.

If you need to do work within 5 seconds, post it to a Handler instead of using the alarm manager?

Answer 3

Try This

public void constructJob(){
Intent alertIntent = new Intent(this, AlarmManagerService.class);
PendingIntent pendingIntent = PendingIntent.getBroadcast(
        this, 0,
        alertIntent,
        PendingIntent.FLAG_UPDATE_CURRENT);

AlarmManager alarmManager = (AlarmManager)getSystemService(Context.ALARM_SERVICE);
alarmManager.setRepeating(
        AlarmManager.RTC_WAKEUP,
        GregorianCalendar.getInstance().getTimeInMillis(),
        1000*5,
        pendingIntent);

}

Answer 4

Try this

    Calendar cur_cal = new GregorianCalendar();

    PendingIntent pintent = PendingIntent.getService(context, 0, intent, PendingIntent.FLAG_CANCEL_CURRENT);
    AlarmManager alarm = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
    alarm.cancel(pintent);
    alarm.setRepeating(AlarmManager.RTC, cur_cal.getTimeInMillis(), interval, pintent);

Answer 5

I had exactly the same problem. I've spent a few hours debugging this, and finally I found out that if the repeating time is set to lower than one minute it always fires the alarm on one minute schedule !?

I followed this example: http://www.compiletimeerror.com/2015/02/how-to-make-alarm-repeat-in-android-code.html#.Vp5UrCorKM8

and it shows the alarm firing on 8 seconds, but in my case it wouldn't.

Than I tried with setting repeating time to few minutes and it worked fine. I also fond out that firing alarm from receiver gives more accurate repeat times (one receiver is for starting alarm manager and it is called by custom intent filter)

Answer 6

Try this code:
Calendar cal = Calendar.getInstance(); alarmManager.setInexactRepeating(AlarmManager.RTC_WAKEUP, cal.getTimeInMillis(), 5000, pendingIntent);