Android设置alarmManager每天触发

Question

在我的应用中，我需要在每天下午 2:00 启动一项服务。现在我写了一次触发警报的代码，每次我打开应用程序都会运行这段代码:

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

    Intent intent = new Intent(this, DownloadReceiver.class);
    PendingIntent pIntent = PendingIntent.getBroadcast(this, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT);

    alarmMgr.cancel(pIntent);

    Calendar cal= Calendar.getInstance();
    cal.setTimeInMillis(System.currentTimeMillis());
    cal.set(Calendar.HOUR_OF_DAY,refreshhour);
    cal.set(Calendar.MINUTE,refreshmin);
    cal.set(Calendar.SECOND, 0);
    // if the scheduler date is passed, move scheduler time to tomorrow
    if (System.currentTimeMillis() > cal.getTimeInMillis()) {        
        cal.add(Calendar.DAY_OF_YEAR, 1);
       }


    if(android.os.Build.VERSION.SDK_INT>=23) {
        alarmMgr.setAndAllowWhileIdle(AlarmManager.RTC_WAKEUP,
        cal.getTimeInMillis(), pIntent);    
        }
    else{
         alarmMgr.setInexactRepeating(AlarmManager.RTC_WAKEUP, cal.getTimeInMillis(),
                        AlarmManager.INTERVAL_DAY, pIntent);
        }

Q1. 如果设备在 Doze 中，我对 23 以上的 sdk 使用 setAndAllowWhileIdle()模式。我在此功能中找不到任何可以将闹钟设置为每天重复的选项。

Q2. 我也有关于 setInexactRepeating() 的问题，通常是通过设置参数 INTERVAL_DAY 设置每天重复，但是在docs , 它说

As of API 19, all repeating alarms will be inexact and subject to batching with other alarms regardless of their stated repeat interval.

这是否意味着 INTERVAL_DAY 不再起作用，那么我如何才能每天设置闹钟而不重新运行此函数并重置 alarmManager？

Answer 1

尝试下面的代码将解决您的问题-

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

boolean flag = (PendingIntent.getBroadcast(this, 0,
                            new Intent("totime.action.string"),
                            PendingIntent.FLAG_NO_CREATE) != null);

if(!flag)
{
    Calendar calendar = Calendar.getInstance();
    calendar.set(Calendar.HOUR_OF_DAY, 14);
    calendar.set(Calendar.MINUTE, 0);
    calendar.set(Calendar.SECOND, 0);
    Intent intent = new Intent("totime.action.string");
    PendingIntent pendingIntent = PendingIntent.getBroadcast(this, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT);
    AlarmManager alarmManager = (AlarmManager) Data_Graph.this.getSystemService(Context.ALARM_SERVICE);
    alarmManager.setRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(),(24*60*60*1000), pendingIntent);

  }