Set a repeating alarm

Question

9I'm making an app that reminds you to take your medicine at some time, so the user gives me the frequency and the period of time, for example:

frequency = 8 hours Period = 7 days

So I'll have make an alarm that triggers every 8 hours for 7 days. This is the code I have now, but it's not working the way I want it... (It is sending all the notifications at the same time, so in the above example it is sending the 21 notifications at once, just a few seconds after I run the code, which means that instead of sending the first one, it is sending all of them)

private void makeAlarm(MedAlarm mAlarm) {

    String medName = mAlarm.getMedName();
    String medDescripcion = mAlarm.getMedDescription();
    String frequency = mAlarm.getMedIntervalHours();
    String duration = mAlarm.getMedIntervalDays();
    int lastitem = ((24 / Integer.parseInt(frequency)) * 
    Integer.parseInt(duration)) - 1;

    String alarmMsg = medName;

    for (int k = 0; k < ((24 / Integer.parseInt(frequency)) * 
         Integer.parseInt(duration)); k++) {// hours

        setAlarm(Integer.parseInt(frequency) * (k + 1), alarmMsg, k + "", 
         "0");
        Log.i("setAlarm", k + " - ");
        Log.i("duration", Integer.parseInt(frequency) * (k + 1) + "");

        if (k == lastitem) {
            setAlarm(Integer.parseInt(frequency) * (k + 1), alarmMsg, k + "", 
            "1");
        }
    }
}

/**
 * @param duration
 * @param name
 * @param id
 * @param lastitem 0 normal item, 1 last item
 */
private void setAlarm(int duration, String name, String id, String lastitem) 
{

    Calendar calendar = Calendar.getInstance();
    calendar.setTimeInMillis(System.currentTimeMillis());

    Intent alertIntent = new Intent(this, AlertReceiver.class);
    alertIntent.putExtra("message", name);
    alertIntent.putExtra("id", id);
    alertIntent.putExtra("lastitem", lastitem);
    PendingIntent pi = PendingIntent.getBroadcast(this, duration++, 
    alertIntent, PendingIntent.FLAG_UPDATE_CURRENT);

    int alarmType = AlarmManager.ELAPSED_REALTIME;
    final int FIFTEEN_SEC_MILLIS = 15000;
    final int HOURS_MILLIS = 3600000 * duration;
    AlarmManager alarmManager = (AlarmManager)
            this.getSystemService(this.ALARM_SERVICE);

    alarmManager.setRepeating(alarmType, SystemClock.elapsedRealtime() + 
    FIFTEEN_SEC_MILLIS,
            HOURS_MILLIS, pi);

    Log.i("intent sent", HOURS_MILLIS + " || ");
}

And the class AlertReciver is the one that sends the notification.

if you could help me with this and tell me what am I missing or if I should aproach this in a different way.

Thank you.

Answer 1

Use alarmManager.set() instead of alarmManager.setRepeating().

Update your setAlarm() method as below:

private void setAlarm(int duration, String name, String id, String lastitem)
{
    Intent alertIntent = new Intent(this, AlertReceiver.class);
    alertIntent.putExtra("message", name);
    alertIntent.putExtra("id", id);
    alertIntent.putExtra("lastitem", lastitem);
    PendingIntent pi = PendingIntent.getBroadcast(this, duration++,
            alertIntent, PendingIntent.FLAG_UPDATE_CURRENT);

    int alarmType = AlarmManager.ELAPSED_REALTIME;
    final int FIFTEEN_SEC_MILLIS = 15000;
    final int HOURS_MILLIS = 3600000 * duration;
    AlarmManager alarmManager = (AlarmManager) this.getSystemService(this.ALARM_SERVICE);

    Calendar calendar = Calendar.getInstance();
    calendar.setTimeInMillis(System.currentTimeMillis() + HOURS_MILLIS);
    alarmManager.set(alarmType, calendar.getTimeInMillis() + FIFTEEN_SEC_MILLIS, pi);

    Log.i("intent sent", System.currentTimeMillis() + HOURS_MILLIS + " || ");
}

Hope this will help~