目标:如果满足特定条件,通知会在每天下午 2 点出现一次。
示例:为简单起见,假设每天都满足通过 Internet 连接检查的条件。如果今天已经是下午 2 点之后,我们将从明天开始通知。例如,用户在周一下午 4 点启动应用程序,然后在周二下午 2 点、周三下午 2 点、周四下午 2 点等收到通知。
问题:在下午 2 点有第一个通知,但随后我在随机时间一遍又一遍地收到相同的通知。
问题似乎只在 Android >= 4.0 上。它在早期的 Android 上运行良好。
这是我发送通知的方式:
public class NotifyService extends Service
{
static final int NOTIFICATION_ID = 1;
// ...
@Override
public IBinder onBind(Intent intent)
{
return null;
}
@Override
public int onStartCommand(Intent intent, int flags, int startId)
{
try
{
Symbol biggest = getBiggestMover();
if (biggest != null)
{
String title = getString(R.string.app_name);
String text = getNotificationText(biggest.symbol, biggest.change);
sendNotification(title, text);
}
}
catch (Exception e)
{
// If there is Internet problem we do nothing, don't want to disturb the user.
e.printStackTrace();
}
return super.onStartCommand(intent, flags, startId);
}
/** @return Symbol which is the biggest mover today. If there is no big mover - null is returned.
* @throws Exception If there is Internet problem. */
private Symbol getBiggestMover() throws Exception
{
Symbol biggest = null;
Symbol[] equities = Network.getTraded(SymbolType.EQUITY);
for (Symbol equity : equities)
{
if (Utilities.isToday(equity.lastTraded) && isBigMove(equity.change) && isBigger(equity, biggest))
{
biggest = equity;
}
}
return biggest;
}
private void sendNotification(String title, String text)
{
Notification notification = new Notification(R.drawable.ic_launcher, text, System.currentTimeMillis());
notification.flags = Notification.FLAG_AUTO_CANCEL;
Intent clickIntent = new Intent(this, MainActivity.class);
PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, clickIntent, PendingIntent.FLAG_CANCEL_CURRENT);
notification.setLatestEventInfo(this, title, text, pendingIntent);
NotificationManager manager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
manager.notify(NOTIFICATION_ID, notification);
}
// ...
}
sendNotification()
在下午 2 点被调用,因为AlarmManager
:
public class ServiceStarter extends BroadcastReceiver
{
@Override
public void onReceive(Context context, Intent intent)
{
setNotificationAlarm(context);
}
/** Set repeating notifications every 24 hours. */
public static void setNotificationAlarm(Context context)
{
Intent intent = new Intent(context, NotifyService.class);
AlarmManager alarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
PendingIntent pendingIntent = PendingIntent.getService(context, 0, intent, PendingIntent.FLAG_CANCEL_CURRENT);
final int oneDay = 24 * 60 * 60 * 1000;
alarmManager.setRepeating(AlarmManager.RTC, getTriggerTime(), oneDay, pendingIntent);
}
private static long getTriggerTime()
{
GregorianCalendar calendar = new GregorianCalendar();
calendar.set(GregorianCalendar.HOUR_OF_DAY, 14);
calendar.set(GregorianCalendar.MINUTE, 0);
calendar.set(GregorianCalendar.SECOND, 0);
calendar.set(GregorianCalendar.MILLISECOND, 0);
if (calendar.before(new GregorianCalendar()))
{
calendar.add(GregorianCalendar.DAY_OF_MONTH, 1);
}
return calendar.getTimeInMillis();
}
}
setNotificationAlarm()
从 2 个地方调用。首先,在应用程序开始时。其次,从上面的代码中,当手机重新启动时(onReceive()
接收BOOT_COMPLETED
)。我这样做是因为当用户关闭手机时,它会AlarmManager
清除它的警报。
所以一切都应该工作,因为alarmManager.setRepeating()
覆盖了以前的警报。
我发现有人有同样的问题,但也没有答案:
https ://groups.google.com/forum/?fromgroups=#!topic/android-developers/t_tDU4PwR3g
同样在这里我发现了类似的问题: http ://comments.gmane.org/gmane.comp.handhelds.android.devel/171471
前段时间我问如何创建这样的通知,所以这是相关的:
每天在特定时间通知