Alarm manager don't work after some time

Question

This is my code. It works correctly, but after some time (about 1 hour) it doesn\'t work. Whats wrong? Thanks in advance.

Answer 1

public void scheduleAlarm(View V)
{
    // time at which alarm will be scheduled here alarm is scheduled at 1 day from current time, 
    // we fetch  the current time in milliseconds and added 1 day time
    // i.e. 24*60*60*1000= 86,400,000   milliseconds in a day       
    Long time = new GregorianCalendar().getTimeInMillis()+24*60*60*1000;

    // create an Intent and set the class which will execute when Alarm triggers, here we have
    // given AlarmReciever in the Intent, the onRecieve() method of this class will execute when

    Intent intentAlarm = new Intent(this, AlarmReciever.class);

    //Get the Alarm Service
    AlarmManager alarmManager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);

    //set the alarm for particular time
    alarmManager.set(AlarmManager.RTC_WAKEUP,time, PendingIntent.getBroadcast(this,1,  intentAlarm, PendingIntent.FLAG_UPDATE_CURRENT));
    Toast.makeText(this, "Alarm Scheduled for Tommrrow", Toast.LENGTH_LONG).show();

}_

AlarmReciever Class

public class AlarmReciever extends BroadcastReceiver
{
    @Override
    public void onReceive(Context context, Intent intent)
    {
        // TODO Auto-generated method stub                                 
        // Your Code     When Alarm willl trigger                             
    }      
}

Answer 2

This is working code. It wakes CPU every 10 minutes and shows notification.

Add to Manifest.xml:

...
<uses-permission android:name="android.permission.WAKE_LOCK"></uses-permission>
...
<receiver  android:process=":remote" android:name="Alarm"></receiver>
...

Code:

public class Alarm extends BroadcastReceiver 
{    
     @Override
     public void onReceive(Context context, Intent intent) 
     {   
         PowerManager pm = (PowerManager) context.getSystemService(Context.POWER_SERVICE);
         PowerManager.WakeLock wl = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, "YOUR TAG");
         wl.acquire();

         // Put here YOUR code.
         Toast.makeText(context, "Alarm !!!!!!!!!!", Toast.LENGTH_LONG).show(); // For example

         wl.release();
     }

     public void SetAlarm(Context context)
     {
         AlarmManager am=(AlarmManager)context.getSystemService(Context.ALARM_SERVICE);
         Intent i = new Intent(context, Alarm.class);
         PendingIntent pi = PendingIntent.getBroadcast(context, 0, i, 0);
         am.setRepeating(AlarmManager.RTC_WAKEUP, System.currentTimeMillis(), 1000 * 60 * 10, pi); // Millisec * Second * Minute
     }

     public void CancelAlarm(Context context)
     {
         Intent intent = new Intent(context, Alarm.class);
         PendingIntent sender = PendingIntent.getBroadcast(context, 0, intent, 0);
         AlarmManager alarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
         alarmManager.cancel(sender);
     }
}