Question

我的代码am.set(AlarmManager.ELAPSED_REALTIME,7*AlarmManager.INTERVAL_DAY, pi); 当我重新启动AlarmManager时将取消。如何重新启动broadcastreceiver，我想计算剩余时间。

Answer 1

如果您想要剩余时间，请保存您设置的时间以在缓存中触发警报

  long timeOfTrigger =  System.getCurrentcurrentTimeMillis() + 7 * AlarmManager.INTERVAL_DAY;

  //use RTC instead of ELAPSED_REALTIME
  //RTC calculates absolute time while 
  //ELAPSED_REALTIME calculates time that has passed since the android system boot.
  am.set(AlarmManager.RTC,timeOfTrigger, pi);
  Context context = getActivity();
  SharedPreferences sharedPref = context.getSharedPreferences(Context.MODE_PRIVATE);

  SharedPreferences.Editor editor = sharedPref.edit();
  editor.putLong("TimeWhenAlarmStarts", timeOfTrigger );
  editor.commit();

这将保存缓存中的触发时间值。然后在任何时候（即使您重新启动了应用程序或手机），您也可以通过

找到剩余时间

 SharedPreferences sharedPref = context.getSharedPreferences(Context.MODE_PRIVATE);
 long timeOfTrigger = sharedPref.getLong("TimeWhenAlarmStarts" , defaultValue ); 
 long remainingtime = timeOfTrigger - System.getCurrentTimeInMillis();
 // the default value can be anything and is used if the SharedPreferences where empty

Alarmmanager当我重新启动时我怎么能保持时间

1 个答案: