Question

我目前正在使用广播接收器启动服务，该设备启动后会在60秒后启动。此广播接收器触发警报，以便我的服务每60秒运行一次。代码如下：

public class ScheduleReceiver extends BroadcastReceiver {
    // Restart service every 60 seconds
    private static final long REPEAT_TIME = 1000 * 60;

    @Override
    public void onReceive(Context context, Intent intent) {
        AlarmManager service = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
        Intent i = new Intent(context, StartServiceReceiver.class);
        PendingIntent pending = PendingIntent.getBroadcast(context, 0, i,PendingIntent.FLAG_CANCEL_CURRENT);

        Calendar cal = Calendar.getInstance();
        // Start 60 seconds after boot completed
        cal.add(Calendar.SECOND, 60);
        // Fetch every 60 seconds
        // InexactRepeating allows Android to optimize the energy consumption
        service.setInexactRepeating(AlarmManager.RTC_WAKEUP, cal.getTimeInMillis(), REPEAT_TIME, pending);
    }
}

以上启动服务如下：

public class StartServiceReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
        Intent service = new Intent(context, PhotoService.class);
        context.startService(service);
    }
}

我想以某种方式修改它，以便我的服务在电话屏幕打开时每60秒运行一次，在关闭时每20分钟运行一次。

最好的方法是什么？屏幕关闭/打开时，我可以动态修改警报吗？

感谢您的帮助，

此致

菲多

Answer 1

好的，我已经找到了如何做到这一点，所以我想我会把它放在这里以防万一其他人好奇。（总是欢迎更优雅的解决方案）：

首先，在我的服务中，我将以下内容添加到OnCreate中：

 @Override
 public void onCreate() {
     super.onCreate();
     // REGISTER RECEIVER THAT HANDLES SCREEN ON AND SCREEN OFF LOGIC
     IntentFilter filter = new IntentFilter(Intent.ACTION_SCREEN_ON);
     filter.addAction(Intent.ACTION_SCREEN_OFF);
     BroadcastReceiver mReceiver = new ScheduleReceiver();
     registerReceiver(mReceiver, filter);
 }

这样做是为了让我的广播接收器可以处理这些事件。显然你不能通过xml中的intent-filters注册这些。

这意味着在创建服务时，它可以确保可以处理这些额外的系统操作。

然后我修改了我的广播接收器：

public class ScheduleReceiver extends BroadcastReceiver {
    private static final int ALARM_ID = 909;

    @Override
    public void onReceive(Context context, Intent intent) {
        SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(context);   
        AlarmManager service = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
        Intent i = new Intent(context, StartServiceReceiver.class);
        PendingIntent pending = PendingIntent.getBroadcast(context, ALARM_ID, i,PendingIntent.FLAG_CANCEL_CURRENT);
        service.cancel(pending);

        Calendar cal = Calendar.getInstance();
        cal.add(Calendar.SECOND, 60); //Delay startup by one minute - This is useful to prevent over utilization of resources at boot

        // Start alarm. Set a long repeat time if the screen is off and a short repeat time if the screen is on
        if (intent.getAction().equals(Intent.ACTION_SCREEN_ON) || intent.getAction().equals(Intent.ACTION_BOOT_COMPLETED)){
            service.setInexactRepeating(AlarmManager.RTC_WAKEUP, cal.getTimeInMillis(), 60000, pending);
        }
        else if (intent.getAction().equals(Intent.ACTION_SCREEN_OFF)){
            service.setInexactRepeating(AlarmManager.RTC_WAKEUP, cal.getTimeInMillis(), 600000, pending);
        }
    }
}

从上面我取消任何具有相同待定意图的当前警报，然后在屏幕关闭/打开时设置新警报。

这似乎对我有用。一如往常，任何改进都是非常受欢迎的。

根据屏幕状态修改触发服务的警报

1 个答案: