I'm writing an Android widget. I want to update it every 1-5 minutes to monitor data from web service but I discovered that android:updatePeriodMillis cannot be less than 30 minutes.
How can I obtain this result with a widget?
Register an AlarmManager service for every 1 min call.
final Intent intent = new Intent(context, UpdateService.class);
final PendingIntent pending = PendingIntent.getService(context, 0, intent, 0);
final AlarmManager alarm = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
alarm.cancel(pending);
long interval = 1000*60;
alarm.setRepeating(AlarmManager.ELAPSED_REALTIME, SystemClock.elapsedRealtime(),interval, pending);
However, pushing updates to app widgets is an expensive operation. Updating every 1 min would force your "update an app widget" code to be resident in memory which keeps running all of the time, and this will also eat up battery pretty significantly.
Use a Handler to sendMessageDelayed(..) a message or postDelayed(..) a Runner.
new Handler().postDelayed( new Runnable() {
public void run() { ... },
60000 /* one minute */
);
Related
I'm writing my android application, which should always show a notification every day at 10:00 AM, no matter what. I use an alarm service to fire notifications at a specific time.
I set notifications to fire in two cases:
when I open the app, I set the alarm service to fire at the nearest 10:00 AM
when I receive notifications, I set the alarm service to fire the next day at 10:00 AM
The problem is: When the interval between the moment when I set alarm service and the actual alarm is greater than approx 12 hours, I just don't receive that notification. If the interval is smaller - I do. But I checked the logs, the alarm service is scheduled properly and for the correct time no matter how I set notifications.
I expect the problem is in the battery optimizer, but I don't know how to verify (and fix) that.
What I tried
In Android I've added my app to exceptions, allowing it to run in the background.
Tested on Huawei P30 Pro, Android 10.
Attaching the code how notifications are scheduled
public class AlarmBroadcastReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
// display notification
NotificationController.scheduleNextNotification(context);
}
}
public class NotificationController {
public static void scheduleNextNotification(Context context) {
Intent myIntent = new Intent(context, AlarmBroadcastReceiver.class);
PendingIntent pendingIntent = PendingIntent.getBroadcast(context, 0, myIntent, 0);
AlarmManager alarmManager = (AlarmManager) context.getSystemService(ALARM_SERVICE);
long notificationTime = getNotificationTime(new Date());
int alarmType = AlarmManager.RTC_WAKEUP;
alarmManager.setExactAndAllowWhileIdle(alarmType, notificationTime, pendingIntent);
}
}
I have an Alarm Manager that runs periodically , but I want to have a specific set of time that it will be running. For Example , lets say that we have a periodic Alarm Manager that is registered with a broadcast receiver and an Action is being performed every 30 minutes. The thing is that I want the Alarm Manager to be active for a specific time lets say 3 hours, so the Alarm manager should goes off 3 hours / 30 minutes or 6 times.
Code to start the define the Alarm Manager:
TimerPeriodic = (AlarmManager)getActivity().getSystemService(Context.ALARM_SERVICE);
Intent intent = new Intent(getActivity(),AlarmReceiver.class);
intent.putExtra(Constants.ALARM_ID, Constants.TIMER_PERIODIC_ID);
TimerPeriodicPendingIntent = PendingIntent.getBroadcast(getActivity(), 0, intent, 0);
Fire Alarm Manager:
long start = TimeUnit.MINUTES.toMillis(StartMinutes);
TimerPeriodic.setRepeating(
AlarmManager.ELAPSED_REALTIME_WAKEUP, SystemClock.elapsedRealtime() + start, start, TimerPeriodicPendingIntent);
Also the alarm Manager should be active if the Application is killed.
Thank you for any help!
It can be acheived by using Sqlite Db. where you store the Alaram ID,count,and repeation (How many time you want to repeat).
when Alarm is trigger (AlarmReceiver.onReceive()) increment the count check with the condition with repeation. if it exceed just cancel it. Hope It will help :)
#Override
public void onReceive(Context context, Intent intent) {
AlarmManager alarmManager = (AlarmManager) context.getApplicationContext().getSystemService(
context.ALARM_SERVICE);
Intent myIntent = new Intent(context, AlarmReceiver.class);
cancelAlarm(reminder.getId(),myIntent,alarmManager);
}
private void cancelAlarm(int notiId,Intent myIntent,AlarmManager alarmManager) {
PendingIntent pendingIntent = PendingIntent.getBroadcast(context, notiId, myIntent, PendingIntent.FLAG_UPDATE_CURRENT);
alarmManager.cancel(pendingIntent);
}
I have to run a piece of code every 5 minutes in my service. Will countdowntimer be killed since the app is not in foreground. If this is the case will alarmanager be better in running the code?
Thanks,
Sahil
I think especially if your code runs in a Service that an AlarmManager is the better alternative. You can use the AlarmManager to start your Service in a 5 minute interval like this:
Calendar calendar = Calendar.getInstance();
Intent intent = new Intent(context, YourService.class);
// Set action of Intent or add extras
long period = 5 * 60 * 1000; // 5 minutes
PendingIntent pendingIntent = PendingIntent.getService(context, alarmId, intent, 0);
AlarmManager alarm = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
alarm.setRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), period, pendingIntent);
If you want to stop your alarm you have to use the same alarmId so it would be best if you put that id in a constant. Also note that you have to restart your alarm every time the phone reboots!
I use this code to setup an alarm in our business application:
private void setupAlarm() {
final Context c = getApplicationContext();
final AlarmManager alarm =
(AlarmManager) c.getSystemService(Context.ALARM_SERVICE);
final Intent i = new Intent(c, AlarmReceiver.class);
final PendingIntent sender =
PendingIntent.getBroadcast(c, 0, i, PendingIntent.FLAG_CANCEL_CURRENT);
final long startFromNow = System.currentTimeMillis()+10000;
final long timer = 5*60*1000;
alarm.setRepeating(AlarmManager.RTC_WAKEUP, startFromNow, timer, sender);
}
I cannot understand why the interval for the alarm is not respected. First alarm starts after 10 seconds (as expected), afterwards it starts every 2 minutes and a bit (122 seconds to 127 seconds), which is wrong. The interval is 5 minutes, or am I wrong?
I use this exact code in a simpler application: one activity that sets the repeating alarm and the receiver just creates a log. There it works.
What could make the AlarmManager act so different?
I have tried to:
use set() and in the alarm receiver use another set() for over 5 minutes: launch at 2 minutes
use setInexactRepeating() instead of setRepeating(): launch at 2 minutes
Any insight would be helpful. Thanks!
Immediate suggestion that comes to mind - make sure you don't set an alarm with the same intent and different value elsewhere. The intent need not be the same object, see the set methods documentation in AlarmManager.
I am currently trying to write alarm manager that will make an alarm go off within a specified period of time, daily. First I check to see if the user has had an alarm set for that for that day:
if ((User.getReminderTime(Home.this) > 0)
&& (dt.getDate() != today.getDate() || dt.getDay() != today
.getDay())) {
AppointmentManager.setFutureAppointmentCheck(this
.getApplicationContext());
User.setLongSetting(this, "futureappts", today.getTime());
}
Then I go and set the actual alarm to go off between 12 and 12:10 of the next day:
public static void setFutureAppointmentCheck(Context con) {
AlarmManager am = (AlarmManager) con
.getSystemService(Context.ALARM_SERVICE);
Date futureDate = new Date(new Date().getTime() + 86400000);
Random generator = new Random();
futureDate.setHours(0);
futureDate.setMinutes(generator.nextInt(10));
futureDate.setSeconds(0);
Intent intent = new Intent(con, FutureAppointmentReciever.class);
PendingIntent sender = PendingIntent.getBroadcast(con, 0, intent,
PendingIntent.FLAG_ONE_SHOT);
am.set(AlarmManager.RTC_WAKEUP, futureDate.getTime(), sender);
}
Now I setup a test environment for this to go off every two minutes and it seems to be working fine, however when I deploy to an actual device, the reciever does not seem to be recieving the alarms. I thought it might be an issue with the device being asleep, so I added the power manager. But it still does not work:
PowerManager pm = (PowerManager) context
.getSystemService(Context.POWER_SERVICE);
PowerManager.WakeLock wl = pm.newWakeLock(
PowerManager.PARTIAL_WAKE_LOCK, "keepAlive");
wl.acquire();
setFutureAppointments(context.getApplicationContext());
AppointmentManager.setFutureAppointmentCheck(context
.getApplicationContext());
User.setLongSetting(context.getApplicationContext(), "futureappts",
new Date().getTime());
wl.release();
Anyone see anything I am doing blatantly wrong or am I going about this incorrectly? thanks for any and all help.
I usually do something more along the lines of:
Intent i = new Intent(this, MyService.class);
PendingIntent pi = PendingIntent.getService(this, 0, i, 0);
AlarmManager am = (AlarmManager) getSystemService(ALARM_SERVICE);
am.cancel(pi); // cancel any existing alarms
am.setInexactRepeating(AlarmManager.ELAPSED_REALTIME_WAKEUP,
SystemClock.elapsedRealtime() + AlarmManager.INTERVAL_DAY,
AlarmManager.INTERVAL_DAY, pi);
This way, you don't have to worry about re-setting the AlarmManager in your Service.
I usually run this bit of code when my app starts (onResume in my main activity) and in a BroadcastReceiver that is set up to receive BOOT_COMPLETED.
I've written a guide on creating Services and using the AlarmManager, which is based on my own experience and a few tips & tricks I picked off from watching a Google I/O talk. If you're interested, you can read it here.
To answer your question below, all I can do is quote the docs:
public void setInexactRepeating (int type, long triggerAtTime, long interval, PendingIntent operation)
Schedule a repeating alarm that has inexact trigger time requirements; for example, an alarm that repeats every hour, but not necessarily at the top of every hour. These alarms are more power-efficient than the strict recurrences supplied by setRepeating(int, long, long, PendingIntent), since the system can adjust alarms' phase to cause them to fire simultaneously, avoiding waking the device from sleep more than necessary.
Your alarm's first trigger will not be before the requested time, but it might not occur for almost a full interval after that time. In addition, while the overall period of the repeating alarm will be as requested, the time between any two successive firings of the alarm may vary. If your application demands very low jitter, use setRepeating(int, long, long, PendingIntent) instead.
In conclusion, it's not very clear. The docs only say that the alarm "may vary". However, it should be important for you to know that the first trigger might not occur for almost a full interval after that time.
This is working, this will shoot alarm after every 5 seconds
private void setRecurringAlarm() {
Logger.d(IConstants.DEBUGTAG, "Setting Recurring Alarm");
Calendar updateTime = Calendar.getInstance();
updateTime.set(Calendar.SECOND, 5);
Intent alarmIntent = new Intent(this, AlarmReceiver.class);
PendingIntent recurringDownload = PendingIntent.getBroadcast(this, 0, alarmIntent, PendingIntent.FLAG_CANCEL_CURRENT);
AlarmManager alarms = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
alarms.cancel(recurringDownload);
alarms.setInexactRepeating(AlarmManager.RTC_WAKEUP, updateTime.getTimeInMillis(), 1000 * 5, recurringDownload); //will run it after every 5 seconds.
}