android – AlarmManager not working-ThrowExceptions

Exception or error:

I need to start the activity AlarmReceiver after 10 seconds (for example). I need it to be activated without running the app. But whether the app runs or not the AlarmReceiver do not get called. Any suggestions?

Intent intent = new Intent(this, AlarmReceiver.class);
PendingIntent pendingIntent = PendingIntent.getBroadcast(this, 111, intent, 0);
AlarmManager alarmManager = (AlarmManager) getSystemService(ALARM_SERVICE);

//alarmManager.set(AlarmManager.RTC_WAKEUP, System.currentTimeMillis() 
                                          //+ (10 * 1000), pendingIntent);
Toast.makeText(this, "Alarm set", Toast.LENGTH_LONG).show();
How to solve:
public class AlarmReceiver extends BroadcastReceiver {

    @Override
    public void onReceive(Context context, Intent intent) {
          String message = "Hellooo, alrm worked ----";
          Toast.makeText(context, message, Toast.LENGTH_SHORT).show();
          Intent intent2 = new Intent(context, TripNotification.class); 
          intent2.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
          context.startActivity(intent2);
    }

    public void setAlarm(Context context){
        Log.d("Carbon","Alrm SET !!");

        // get a Calendar object with current time
         Calendar cal = Calendar.getInstance();
         // add 30 seconds to the calendar object
         cal.add(Calendar.SECOND, 30);
         Intent intent = new Intent(context, AlarmReceiver.class);
         PendingIntent sender = PendingIntent.getBroadcast(context, 192837, intent, PendingIntent.FLAG_UPDATE_CURRENT);

         // Get the AlarmManager service
         AlarmManager am = (AlarmManager) context.getSystemService(context.ALARM_SERVICE);
         am.set(AlarmManager.RTC_WAKEUP, cal.getTimeInMillis(), sender);
    }
}

This is the final code i managed to get working. You need to add

 <receiver  android:process=":remote" android:name="AlarmReceiver"></receiver>

just above the </application> tag in Manifest file.

This will set an alarm to trigger in 30 seconds after calling the method SetAlarm()

###

As of now, it’s not possible to start Alarm without running the app, you must once run your respective app to activate your alarm..
For this….!!

In Your ALARM_ACTIVITY :

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

Intent intent = new Intent(ALARM_ACTIVITY.this,ALARM_RECEIVER.class); 

PendingIntent pendingIntent = PendingIntent.getBroadcast(SetReminder.this, ID, intent, PendingIntent.FLAG_UPDATE_CURRENT);

alarmManager.set(AlarmManager.RTC_WAKEUP, System.currentTimeInMillis() + 1000, pendingIntent);

In Your ALARM_RECEIVER :

NotificationManager notificationManager = (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);

PendingIntent pendingIntent = PendingIntent.getActivity(context, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT);

notification = new Notification(R.drawable.alarmicon, "charSequence", System.currentTimeMillis());

notification.setLatestEventInfo(context, "alarmTitle", "charSequence", pendingIntent);

notification.flags |= Notification.FLAG_AUTO_CANCEL;

notificationManager.notify(1, notification);

###

And if it is still not working getting rid of the android:process=":remote" part may help. Worked for me 🙂

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So long as your app has run once to establish the alarm with AlarmManager, the alarm fires your intent even if your app isn’t running. The exception is after a device restart. To start an alarm when the device restarts, implement a BroadcastReceiver to set the alarm, and add the receiver to your manifest for ACTION_BOOT_COMPLETED:

<receiver android:name=".SampleBootReceiver"
        android:enabled="false">
    <intent-filter>
        <action android:name="android.intent.action.BOOT_COMPLETED"></action>
    </intent-filter>
</receiver>

###

Also, In addition to the above,I think the methods in the AlarmActivity should be in the oncreate method of the LAUNCHER activity.. In this case, the Alarm Activvity should be the LAUNCHER activity of the app. this solved my problem

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