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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.

Android: Start & close application at user specified times

How can I start my application on a time specified by the user.
Lets say start time is 8:00 am and end time is 4:00p.m
I am storing the value of start time and end time in shared preference.
public static synchronized void scheduleTimeoutCheck(final int time) {
final Calendar calendar = Calendar.getInstance();
calendar.set(Calendar.HOUR_OF_DAY, time / 100);
calendar.set(Calendar.MINUTE, time % 100);
calendar.set(Calendar.SECOND, 1); // Add 1 second of additional delay
if (calendar.getTimeInMillis() - Calendar.getInstance().getTimeInMillis() <= 0) {
// Time has already past, schedule for next day
calendar.add(Calendar.DAY_OF_MONTH, 1);
}
new Timer(true).schedule(new TimerTask() {
#Override
public void run() {
// "its time for scheduleTimeoutCheck
/*if (Utility.checkSystemTimeout())
{*/
// Re - schedule this for the next day //
Utility.checkLockdownAppSchedule();
// }
}
}, calendar.getTime());
System.out.println("Timeout Check is scheduled to run at " + calendar.getTime().toString());
}

What u wanna do is fully described here
First schedule your times somewhere, like in your onCreate():
//create new calendar instance for your start time
Calendar startTime= Calendar.getInstance();
//set the time to 4AM or your USER SPECIFIED start time
startTime.set(Calendar.HOUR_OF_DAY, 4);
startTime.set(Calendar.MINUTE, 0);
startTime.set(Calendar.SECOND, 0);
AlarmManager am = (AlarmManager) LayoutActivity.this.getSystemService(ALARM_SERVICE);
//create a pending intent to be called at 4AM
PendingIntent startPI = PendingIntent.getService(yourActivity.this, 0, new Intent("startApplicationReceiver"), PendingIntent.FLAG_UPDATE_CURRENT);
//schedule time for pending intent, and set the interval to day so that this event will repeat at the selected time every day
am.setRepeating(AlarmManager.RTC_WAKEUP, startTime.getTimeInMillis(), AlarmManager.INTERVAL_DAY, startPI);
//----------------------------------------------------
//create new calendar instance for your end time
Calendar endCalender = Calendar.getInstance();
//Set the time to 8PM or your USER SPECIFIED end time
endCalender.set(Calendar.HOUR_OF_DAY, 8);
endCalender.set(Calendar.MINUTE, 0);
endCalender.set(Calendar.SECOND, 0);
//create a pending intent to be called at 8 AM
PendingIntent endPI= PendingIntent.getService(yourActivity.this, 0, new Intent("endApplicationReceiver"), PendingIntent.FLAG_UPDATE_CURRENT);
//schedule time for pending intent, and set the interval to day so that this event will repeat at the selected time every day
am.setRepeating(AlarmManager.RTC_WAKEUP, endCalender.getTimeInMillis(), AlarmManager.INTERVAL_DAY, endPI);
Add your Alarm classes:
Start time receiver:
public class startApplicationReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
try { //Start your application
Intent intent = new Intent();
intent.setClassName("package.name", "<your_package_name>");
startActivity(intent);
} catch (NameNotFoundException e) { //You don't have the application installed
Log.e(TAG, e.getMessage());
}
//!!!If you WANT to repeat the start application alarm EVERY day
//Comment/Remove the next 4 lines
//Cancel start time alarm
Intent intent = new Intent(yourActivity.this, startApplicationReceiver.class);
PendingIntent startPI = PendingIntent.getBroadcast(this, 0, intent, 0);
AlarmManager alarmManager = (AlarmManager) getSystemService(ALARM_SERVICE);
alarmManager.cancel(startPI);
}
}
End time receiver
public class endApplicationReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
//finish your application
finish();
//!!!If you WANT to repeat the endapplication alarm EVERY day
//Comment/Remove the next 4 lines
//Cancel end time alarm
Intent intent = new Intent(yourActivity.this, endApplicationReceiver.class);
PendingIntent endPI = PendingIntent.getBroadcast(this, 0, intent, 0);
AlarmManager alarmManager = (AlarmManager) getSystemService(ALARM_SERVICE);
alarmManager.cancel(endPI);
}
}
And the last thing u need to do is register your receivers in your
Manifest.XML:
<receiver android:name="startAlarm" >
<intent-filter>
<action android:name="startApplicationReceiver" >
</action>
</intent-filter>
</receiver>
<receiver android:name="endAlarm" >
<intent-filter>
<action android:name="endApplicationReceiver" >
</action>
</intent-filter>
</receiver>
This should help u out.
Note: you must have started your application manually at least once, to register the alarm receivers.

You can use the AlarmManager for achieving such functionality.
To take a good grasp on how to implement it, you can study this good article. and this one by Java Code Geeks.

Start application it means you want to start activity at exact time?
It is not good user case i think. But for this task you have to use AlarmManager, plus a Service with your logic (Service will not visible for user).
If you want notify user about something you can use NotificationManager. Or in last case you can start semitransparent activity with dialog. Remember that for starting activity from service you should setkey SINGLE_TASK

Alarmmanager going off on reboot...but its set for 7 days ahead?

I'm failing to see why this alarm is going off on a reboot...I am setting it 7 days ahead here -
Intent intent = new Intent(MainActivity.this, Reminder.class);
PendingIntent pendingIntent = PendingIntent.getBroadcast(
MainActivity.this, 1, intent, 1);
AlarmManager am = (AlarmManager) getSystemService(ALARM_SERVICE);
try {
am.cancel(pendingIntent);
} catch (Exception e) {
System.out.println("Derp");
}
Calendar calendar = Calendar.getInstance();
calendar.add(Calendar.DATE, 7);
long time = calendar.getTimeInMillis();
am.set(AlarmManager.RTC_WAKEUP, time,
pendingIntent);
Here is my manifest that I have set for alarm to stick around on a reboot - Reminder is the class receiving the alarm-
<receiver android:name="com.practicum.notifications.Reminder" >
<intent-filter>
<action android:name="android.intent.action.BOOT_COMPLETED" />
</intent-filter>
</receiver>

By default, all alarms are canceled when a device shuts down. To prevent this from happening, you can design your application to automatically restart a repeating alarm if the user reboots the device. This ensures that the AlarmManager will continue doing its task without the user needing to manually restart the alarm.
You have to manually reset the alarm once again in Bootup Receiver
public class SampleBootReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
if (intent.getAction().equals("android.intent.action.BOOT_COMPLETED")) {
// Set the alarm here.
}
}

All alarms are shut off when you power off the Android device.
You need to call setRepeating method
public class AlarmReceiver extends BroadcastReceiver {
private static final int PERIOD=5000;
#Override
public void onReceive(Context ctxt, Intent i) {
scheduleAlarms(ctxt);
}
static void scheduleAlarms(Context ctxt) {
AlarmManager am = (AlarmManager) ctxt.getSystemService(Context.ALARM_SERVICE);
Intent i = new Intent(ctxt, YourService.class);
PendingIntent pi = PendingIntent.getService(ctxt, 0, i, 0);
mgr.setRepeating(AlarmManager.ELAPSED_REALTIME,
SystemClock.elapsedRealtime() + PERIOD, PERIOD, pi);
}
}
Check this answer from CommonsWare.

For future reference, I misunderstood how receving the boot complete action worked. I had the intent filter in both of my receiver classes so they were both running, when instead I needed an intent filter on a new broadcastreceiver class to RESET my alarmmanagers.

Hovering toast every 5 minutes

I've seen several examples on how to make some event to be repeated even when the app isnt running, but still I'm not sure if I got it.
With AlarmManager you can make your app to wake up to do something in some fixed interval without it consuming system resources between the periods, right?
But can it be to show up a toast over your current activity instead of having an Activity with a layout for it?

AlarmReceiver class:
public class AlarmReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
// this is where to start activity or service to launch toast message
}
}
In activity or boot receiver:
private static final int PERIOD = 60000; //or whatever you need for repeating alarm
AlarmManager mgr = (AlarmManager)context.getSystemService(Context.ALARM_SERVICE);
Intent alIntent = new Intent(context, AlarmReceiver.class);
PendingIntent pi = PendingIntent.getBroadcast(context, 0, alIntent, 0);
mgr.setRepeating(AlarmManager.ELAPSED_REALTIME_WAKEUP, SystemClock.elapsedRealtime() + 60000, PERIOD, pi);
In AndroidManifest, add:
<receiver android:name=".AlarmReceiver"></receiver>

In android, is it possible to use more than one AlarmManager with different repeat values in a single application?

I'm developing an application for mobile and tablet using android 2.3**
I want to do some operations namely Operation-A and Operation-B. Both perform some pocess.
I want to repeat the Operation-A and Operation-B is performed every 1 hour time interval
Operation-A is performed before the 10 minutes of Operation-B
Operation-B is performed when the time is 0.00,1.00,2.00,3.00,....,23.00 (I'm using railway time. So it is not confused for am or pm).
Operation-A is performed when the time is 0.50,1.50,2.50,3.50,....,23.50
The above scenarios is possible in android or not.
All are give your ideas for the above scenarios.
I'm planning to use AlarmManager. AlarmManager is android system service. It is used to notify the application every 1 hour.
I plan to use an AlarmManager for Operation-A and another AlarmManager for Operation-B.
My doubt is ,In android is it possible to use more than one AlarmManager with different repeat values in a single application?
All your ideas are welcome.

Yes this task will done with help of AlarmManager with reperating functionality. First you need to create two receiver class which will receive events . and then need to setup repeating alarm .
private void setAlarm1()
{
AlarmManager am = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
Calendar calendar = Calendar.getInstance();
calendar.setTimeInMillis(System.currentTimeMillis());
calendar.add(Calendar.HOUR, 1);
Intent intent = new Intent(this, AlarmReceiver.class);
PendingIntent pendingIntent = PendingIntent.getBroadcast(this, 0,
intent, PendingIntent.FLAG_CANCEL_CURRENT);
am.setRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), 1000*60*60, pendingIntent);
}
private void setAlarm2()
{
AlarmManager am = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
Calendar calendar = Calendar.getInstance();
calendar.setTimeInMillis(System.currentTimeMillis());
calendar.add(Calendar.MINUTE, 50);
Intent intent = new Intent(this, AlarmReceiver_1.class);
PendingIntent pendingIntent = PendingIntent.getBroadcast(this, 0,
intent, PendingIntent.FLAG_CANCEL_CURRENT);
am.setRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), 1000*60*50, pendingIntent);
}
public class AlarmReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
}
}
public class AlarmReceiver_1 extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
}
}
In menifest, you need to declare the classes as below.
<receiver android:name=".AlarmReceiver" />
<receiver android:name=".AlarmReceiver_1" />