Develop Reference

dynamic alarm manager at midnight

my mean goal is to run a task periodically at midnight (00:00:00)
but the user can set the period based on the interval (daily, weekly , monthly)
let's assume that this job is a backup Scheduling.
this task will triggred at midnight but based on the user preference (midnight everyday, every week , or monthly ), and if the phone was in the doze mode or even off , wait untill the next start and start backup.
when i start implementing the code , i started with JobService and JobScheduler , but unfortunately i learned that i can set the repetitive but i can't set the exact time, so the last solution was to work with alarmmanager.
i use this code for triggering the alarm :
public static void setTheTimeToStartBackup(Context context,String periode) {
int DATA_FETCHER_RC = 123;
AlarmManager mAlarmManager = (AlarmManager)context.getSystemService(Context.ALARM_SERVICE);
Calendar calendar = Calendar.getInstance();
Intent intent = new Intent(context, BackUpAlarmRecevier.class);
PendingIntent pendingIntent = PendingIntent.getBroadcast(context, DATA_FETCHER_RC,intent, PendingIntent.FLAG_UPDATE_CURRENT);
long interval = 0;
switch (periode){
case "never":
return;
case "daily":
alarmStartTime.set(Calendar.HOUR_OF_DAY, 0);
interval = AlarmManager.INTERVAL_DAY;
break;
case "weekly":
alarmStartTime.set(Calendar.DAY_OF_WEEK, 1);
interval = AlarmManager.INTERVAL_DAY*7;
break;
case "monthly":
alarmStartTime.set(Calendar.WEEK_OF_MONTH, 1);
interval = AlarmManager.INTERVAL_DAY*30;
break;
}
alarmStartTime.set(Calendar.HOUR_OF_DAY, 0);
alarmStartTime.set(Calendar.MINUTE, 0);
alarmStartTime.set(Calendar.SECOND, 0);
mAlarmManager.setRepeating(AlarmManager.RTC_WAKEUP,calendar.getTimeInMillis(),interval, pendingIntent);
Log.e("Alarm","Set for midnight");
}
this is my receiver :
public class BackUpAlarmRecevier extends BroadcastReceiver {
SharedPreferences preferences;
#Override
public void onReceive(Context context, Intent intent) {
Log.e("BackUpAlarmReciver","Triggred");
PowerManager pm = (PowerManager) context.getSystemService(Context.POWER_SERVICE);
PowerManager.WakeLock wl = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, "TAG:APP");
wl.acquire();
sendNotification(context);// simple notification...
Toast.makeText(context, "Alarm !!", Toast.LENGTH_LONG).show();
startBackupProcess();
wl.release();
}}
the problem is task never start.
so i went to test it with less time interval (15min as the minimum possible as i read ), so i change my first function setTheTimeToStartBackup to this :
public static void setTheTimeToStartBackup(Context context,String periode) {
int DATA_FETCHER_RC = 123;
AlarmManager mAlarmManager = (AlarmManager)context.getSystemService(Context.ALARM_SERVICE);
Calendar calendar = Calendar.getInstance();
calendar.set(Calendar.SECOND, 55);
Intent intent = new Intent(context, BackUpAlarmRecevier.class);
PendingIntent pendingIntent = PendingIntent.getBroadcast(context, DATA_FETCHER_RC,intent, PendingIntent.FLAG_UPDATE_CURRENT);
mAlarmManager.setRepeating(AlarmManager.RTC_WAKEUP,calendar.getTimeInMillis(),AlarmManager.INTERVAL_FIFTEEN_MINUTES, pendingIntent);
Log.e("Alarm","Set for midnight");
}
and exactly the same problem , nothing started, no log , no notification , nothing.
and i already set the Receiver in my manifest with all permission like that :
<receiver android:name=".job.BackUpAlarmRecevier"
android:enabled="true"
android:process=":remote"
android:exported="true">
<intent-filter>
<action android:name="android.intent.action.BOOT_COMPLETED" />
</intent-filter>
</receiver>
what im doing wrong in both cases ? and if it work , this code will persist for ever or i need to set it again each time ?
thanks :)
EDIT:
i call my function setTheTimeToStartBackup in the MainActivity.

You could set it to occur at midnight if you did the appropriate time calculations. Dynamically get the current time and date, calculate when to register the broadcast for the alarm manager. Customize the onReceive method to set another alarm at 12pm again.
Either way you can trigger a broadcast receiver by registering your receiver manually.
Broadcast receiver class:
public class AlarmReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
System.out.println("Alarm received!! ");
// Register alarm again here.
}
}
Code to register a receiver with a custom intent filter.
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
AlarmManager mAlarmManager = (AlarmManager)getApplicationContext().getSystemService(Context.ALARM_SERVICE);
getApplicationContext().registerReceiver(new AlarmReceiver(), new IntentFilter("AlarmAction"));
PendingIntent broadcast = PendingIntent.getBroadcast(this, 0, new Intent("AlarmAction"), 0);
// Add dynamic time calculations. For testing just +100 milli.
mAlarmManager.set(AlarmManager.RTC_WAKEUP, System.currentTimeMillis() + 100, broadcast);
;
}
You could achieve what you wanted through a background service.

My suggestion would be to turn the problem around a bit.
Create three topics on Firebase (daily, weekly, monthly). Subscribe users to appropriate topics. Have a Firebase function that is triggered by CRON job which sends the data notification down to the device, this data notification should schedule one-time WorkManager job for the update. This way you can control everything from server-side, if the phone is off, it will still execute as soon as it turns on and you don't need to manually take care of catching the Boot completed with alarm manager etc.

My AlarmManager triggers every time service is run, not at set time

I am trying to create a SMS-app which sends out SMS at one set time of day. For this I have created two services SendMessagePeriodicService and SendMessageService.
This is my SendMesagePeriodicService, which is supposed to trigger SendMessageService at a set time of day. The problem is that it triggers every time the onStartCommand-method is called...
public class SendMessagePeriodicService extends Service {
#Nullable
#Override
public IBinder onBind(Intent intent) {
return null;
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) { //FIXME
Calendar cal = Calendar.getInstance();
Intent i = new Intent(this, SendMessageService.class);
PendingIntent pintent = PendingIntent.getService(this, 0, i, PendingIntent.FLAG_UPDATE_CURRENT);
cal.set(Calendar.MINUTE, PreferenceManager.getDefaultSharedPreferences(getApplicationContext()).getInt("minute", -1));
cal.set(Calendar.HOUR_OF_DAY, PreferenceManager.getDefaultSharedPreferences(getApplicationContext()).getInt("hour", -1));
AlarmManager alarm = (AlarmManager)getSystemService(Context.ALARM_SERVICE);
alarm.setRepeating(AlarmManager.RTC_WAKEUP, cal.getTimeInMillis(), AlarmManager.INTERVAL_DAY, pintent);
return Service.START_NOT_STICKY;
}
}
I have also checked that the values in the sharedPreferences are correct...
Does anyone have any idea why this is happening?

I would do that by setting the alarmmanager in the activity and than use BroadcastReceiver to send the sms when the alarm fires.
I use the same technique to start a notification on a specific time.
I think I have read somewhere the you use services nowadays only for fileoperations. But I´m not 100%.

It seems that the reason this happens was that the time I set for trigger time was in the past. This means that AlarmManager triggers immediately and not the next time this set time occurs.

Set alarm in service and receive callback in the same service

My ReminderService uses the AlarmManager to inform the user about an upcoming event at a specific time. Is it possible that the AlarmManager informs the same service (ReminderService) or do I need to start another service to catch the pending intent? Until now this mechanism looks like this
public class ReminderService extends Service {
// ...
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
// ..
/* When the alarm goes off the NotifyService will be started. Is it possible to inform **this**
service (ReminderService) and to handle the alarm? */
Intent alarmIntent = new Intent(this, NotifyService.class);
alarmIntent.putExtra(TodoTask.PARCELABLE_KEY, task);
AlarmManager alarmManager = (AlarmManager) getSystemService(ALARM_SERVICE);
PendingIntent pendingIntent = PendingIntent.getService(this, 0, alarmIntent, 0);
Calendar calendar = Calendar.getInstance();
Date date = new Date(reminderTimeStamp*1000);
calendar.setTime(date);
alarmManager.set(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), pendingIntent);
}
}

yes u can. You just need to change this line:
Intent alarmIntent = new Intent(this, NotifyService.class);
to this:
Intent alarmIntent = new Intent(this, ReminderService.class);
that way the ReminderService will receive the intent with TodoTask.PARCELABLE_KEY inside this same method public int onStartCommand(Intent intent, int flags, int startId)
Remember that there no guarantee that this will be the same instance of the service. If the service you're running get killed by the system a new instance of it will be started to handle the intent.
Also remember all the sleep and doze mode stuff mentioned by Larry_Schiefer on his answer.

You can use the same Service (or other component) to receive an alarm. However, not that your alarm will not be guaranteed to be delivered on schedule when in low power. Use a WakefulReceiver or your own combination of BroadcastReceiver and a wakelock to get your Service going. See this article for more details on power state and alarms.
Also, note that starting with Android Marshmallow your wakelocks will be ignored if the device is in Doze mode. There are other things you'll have to do to wake the device at a certain time when in Doze.

Android repeating alarm not repeating correctly

I have an alarm that I am wanting to repeat around every 5 minutes. For testing purposes, I have it set to repeat once every 5 seconds instead, as such:
AlarmManager alarmManager = (AlarmManager)getActivity().getSystemService(getActivity().ALARM_SERVICE);
Intent intent = new Intent(getActivity(), CoordinateAlarmReceiver.class);
PendingIntent pendingIntent = PendingIntent.getService(getActivity(), 1, intent, 0);
int repeatSeconds = 5;
alarmManager.setInexactRepeating(AlarmManager.RTC_WAKEUP, System.currentTimeMillis(),
repeatSeconds * 1000, pendingIntent);
And the receiving IntentService prints a log statement when it receives the alarm. However, it fires around once every minute and a half instead of once every 5 seconds, where is it set incorrectly? I have also tried using setRepeating() instead of setInexactRepeating() but I get the same results.
Here is my alarm receiver:
public class CoordinateAlarmReceiver extends IntentService {
public CoordinateAlarmReceiver(){
super("CoordinateAlarmReceiver");
}
/*
Alarm received, get new contacts which then shows notification
*/
#Override
protected void onHandleIntent(Intent intent) {
MyLog.i("coordinate alarm received");
//new GetNewContactsTask(this).execute();
}
}

I assume you are on api 19 or above. The alarmmanager documentations says:
Note: Beginning with API 19 (KITKAT) alarm delivery is inexact: the OS will shift alarms in order to minimize wakeups and battery use. There are new APIs to support applications which need strict delivery guarantees; see setWindow(int, long, long, PendingIntent) and setExact(int, long, PendingIntent). Applications whose targetSdkVersion is earlier than API 19 will continue to see the previous behavior in which all alarms are delivered exactly when requested.
You tried using setRepeating() but on api 19 and above this calls setInexactRepeating(). On 19 and above you
setInexactRepeating(): 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.
This explains your weird result.
If you want to set is at a excat time, you should use setExact. Unfortunalety there is no setExactRepating so you have to create this yourself. Schedule a new alarm after one executes or something like that.
Note in the alarmmanager documentation:
Note: The Alarm Manager is intended for cases where you want to have your application code run at a specific time, even if your application is not currently running. For normal timing operations (ticks, timeouts, etc) it is easier and much more efficient to use Handler.
Maybe you should take a look at this.

I had a similar problem in which I needed a Service fired every 15 seconds... I did the following.
I have a class that extends Application called MyApplication. This class holds an instance of an alarm manager.
public class MyApplication extends Application {
private MyAlarmManager alarmMgr;
#Override
public void onCreate() {
Log.d(TAG, "MyApplication onCreate");
super.onCreate();
Log.d(TAG, "initing alarmMgr ...");
alarmMgr = new MyAlarmManager(this);
}
public MyAlarmManager getAlarmManager(){
return alarmMgr;
}
}
An AlarmManager called MyAlarmManager creates, starts & stops the alarms AND NOW sets the next alarm for this one service.
public class MyAlarmManager {
private MyApplication mApp;
private Intent intent;
private PendingIntent pendingIntent;
private AlarmManager alarmMgr;
private static final long FREQUENCY = 15000;
public MyAlarmManager(Context context) {
mApp = (MyApplication) context;
// Android alarm service
alarmMgr = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
// service to be fired every 15 seconds
intent = new Intent(context, MyService.class);
pendingIntent = PendingIntent.getService(context, 1, intent, PendingIntent.FLAG_UPDATE_CURRENT);
setNextAlarm();
}
public void setNextAlarm(){
Log.d(TAG, "setting next alarm...");
alarmMgr.set(AlarmManager.RTC_WAKEUP, (System.currentTimeMillis() + FREQUENCY), pendingIntent);
}
private void stopAlarms(){
Log.d(TAG, "stopping Alarms");
alarmMgr.cancel(pendingIntent);
}
}
When the Service is fired I get an instance of MyApplication, get the AlarmManager and schedule the next alarm.
public class MyService extends Service {
MyApplication mApp;
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
Log.d(TAG, "in onStartCommand");
// init the app reference if needed
if (mApp == null) {
Log.d(TAG, "app was null. Creating now...");
mApp = (MyApplication) getApplicationContext();
}
// schedule the next zone check
mApp.getAlarmMgr().setNextAlarm();
// custom functionality ...
}

AlarmManager only lets one Service through when used with setRepeating in Android

I've been struggling with this for a couple of days. What I want to do is run a service periodically, about 2-3 minutes apart. I have an Activity that is responsible for the interface and setting up the first alarm.
The alarm is configured by a BroadcastReceiver which looks like this:
public class Receiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
String message = "Alarm worked";
Toast.makeText(context, message, Toast.LENGTH_SHORT).show();
setAlarm(context);
}
public void setAlarm(Context context){
AlarmManager am = (AlarmManager) context.
getSystemService(Context.ALARM_SERVICE);
Intent intent = new Intent(context, Receiver.class);
PendingIntent pi = PendingIntent.getBroadcast(context,
0, intent, PendingIntent.FLAG_UPDATE_CURRENT);
Intent dailyUpdater = new Intent(context, DiscoveryService.class);
context.startService(dailyUpdater);
am.set(AlarmManager.RTC_WAKEUP, System.currentTimeMillis()
+ (1000 * 30) , pi);
}
}
I've tried using setRepeating for AlarmManager, but it still has the same effect. What happens is that the AlarmManager works how it should, it fires an Intent which the receiver gets and executes onReceive periodically, as it should. However, it executes the service only the first time. After the first time, the alarms still go off, but the service is not executed.
I read some threads from people with similar problems, and one of them mentioned that PendingIntent lasts for only one send. Thus, I opted out to setting the alarm every time so I can set pendingIntent flag for updating every time.
I tried making my service an intentService, which is fine, but then my bluetooth scanner inside the service does not work because intentService thread terminates without waiting for my bluetooth discovery to finish.
Anyone have any idea what can help me?
Here is part of my service:
public class DiscoveryService extends Service {
public void onCreate() {
super.onCreate();
Toast.makeText(this, "MyAlarmService.onCreate()",
Toast.LENGTH_LONG).show();
findEverything();
}
}
EDIT: This is the code that I currently have.
public void onReceive(Context context, Intent intent) {
String message = "Alarm worked";
Toast.makeText(context, message, Toast.LENGTH_SHORT).show();
Intent dailyUpdater = new Intent(context, DiscoveryService.class);
context.startService(dailyUpdater);
}
public void setAlarm(Context context){
// get a Calendar object with current time
AlarmManager am=(AlarmManager)context.
getSystemService(Context.ALARM_SERVICE);
Intent intent = new Intent(context, Receiver.class);
PendingIntent pi = PendingIntent.getBroadcast(context, 0, intent,
PendingIntent.FLAG_UPDATE_CURRENT);
am.setRepeating(AlarmManager.RTC_WAKEUP, System.currentTimeMillis(),
(1000 * 30) , pi);
}

What happens is that the AlarmManager works how it should, it fires an Intent which the reciever gets and executes onReceive periodically, as it should. However, it executes the service only the first time. After the first time, the alarms still go off, but the service is not executed.
You are calling startService() once when you are scheduling the alarm. You are not calling startService() at all from your BroadcastReceiver. Yet you are scheduling the alarm via the BroadcastReceiver. Hence, when the alarm goes off, the service will not be sent a command, because you are not sending it a command.
I read some threads from people with similar problems, and one of them mentioned that PendingIntent lasts for only one send.
That is only if you use FLAG_ONE_SHOT.
Anyone have any idea what can help me?
Call startService() from your onReceive() method, instead of from your setAlarm() method. Also, add in all the WakeLock management logic, since you are using a _WAKEUP alarm and you are not able to use my WakefulIntentService.