应用程序关闭时未触发通知

Question

我正在尝试设置一个警报管理器，使其每 15 分钟运行一次，检查是否有任何内容已添加到数据库中，然后显示通知。但是，虽然我只是对此进行测试，但我试图在 60 秒后显示通知。

以下代码在应用程序打开或最小化时运行良好，但在应用程序关闭时永远不会被调用。

主要Activity (onCreate())

Intent alarm = new Intent(this.context, AlarmReceiver.class);
    boolean alarmRunning = (PendingIntent.getBroadcast(this.context, 0, alarm, PendingIntent.FLAG_NO_CREATE) != null);
    if (!alarmRunning) {
        PendingIntent pendingIntent = PendingIntent.getBroadcast(this.context, 0, alarm, 0);
        AlarmManager alarmManager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
        alarmManager.setRepeating(AlarmManager.ELAPSED_REALTIME_WAKEUP, SystemClock.elapsedRealtime(), 60000, pendingIntent);
    }

报警接收器

public class AlarmReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {
    Intent background = new Intent(context, BackgroundService.class);
    context.startService(background);
}

}

后台服务

public class BackgroundService extends Service {

private final String TAG = getClass().getName();

private Boolean isRunning;
private Context context;
private Thread backgroundThread;

@Nullable
@Override
public IBinder onBind(Intent intent) {
    return null;
}

@Override
public void onCreate() {
    this.context = this;
    this.isRunning = false;
    this.backgroundThread = new Thread(myTask);
}

private Runnable myTask = new Runnable() {
    @Override
    public void run() {
        Log.d(TAG, "THE BACKGROUND SERVICE IS RUNNING");
        //Run actions
        showNotification(context);
        //
        stopSelf();
    }
};

private void showNotification(Context context) {
    Uri soundUri = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);

    NotificationCompat.Builder mBuilder =   new NotificationCompat.Builder(context)
            .setSmallIcon(R.drawable.icon)
            .setContentTitle("Notification!") // title for notification
            .setContentText("Alarm Received")
            .setSound(soundUri)// message for notification
            .setAutoCancel(true); // clear notification after click
    NotificationManager mNotificationManager =
            (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);
    mNotificationManager.notify(0, mBuilder.build());
}

@Override
public void onDestroy() {
    this.isRunning = false;
}

@Override
public int onStartCommand(Intent intent, int flags, int startId) {
    if (!this.isRunning) {
        this.isRunning = true;
        this.backgroundThread.start();
    }
    return START_STICKY;
}

}

清单

<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />

    <service android:name=".notification.BackgroundService" />

    <receiver android:name=".notification.AlarmReceiver"
        android:process=":remote"
        android:enabled="true"
        android:exported="true">
        <intent-filter>
            <action android:name="android.intent.action.BOOT_COMPLETED" />
        </intent-filter>
    </receiver>

我已经阅读了几篇文章，但似乎找不到如何解决这个问题的答案，以便通知仍然可以 shown/checked 在应用程序关闭时关闭我的意思是用户删除了运行应用列表中的应用。

Answer 1

尝试更改闹钟代码：

        final int ALARM_ID = 1234; // your alarm id
        startAlarm(600); // trigger after 10 minutes

        public void startAlarm(int seconds) { // set alarm in seconds
            Intent intent = new Intent(this, AlarmReceiver.class);
            AlarmManager alarmManager = (AlarmManager) getSystemService(ALARM_SERVICE);
            PendingIntent pendingIntent = PendingIntent.getBroadcast(this, ALARM_ID, intent, PendingIntent.FLAG_CANCEL_CURRENT);

            alarmManager.set(AlarmManager.RTC_WAKEUP, System.currentTimeMillis() + (seconds * 1000), pendingIntent);
        }

        public void cancelAlarm() { // to cancel alarm before trigger   
            Log.d("lucas", "cancelAlarm");
            Intent intent = new Intent(this, AlarmReceiver.class);
            AlarmManager alarmManager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
            PendingIntent pendingIntent = PendingIntent.getBroadcast(this, ALARM_ID, intent, PendingIntent.FLAG_CANCEL_CURRENT);

            alarmManager.cancel(pendingIntent);
            pendingIntent.cancel();
        } 

        public boolean hasAlarm() { // check alarm is running
            Intent intent = new Intent(this, AlarmReceiver.class);
            return (PendingIntent.getBroadcast(this, ALARM_ID, intent, PendingIntent.FLAG_NO_CREATE) != null);
        }

不调用stopSelf()方法，他可能会杀掉应用。正是后台的运行服务让应用程序进程保持活动状态。如果没有服务运行，系统可能会终止您的应用、删除通知并取消您的闹钟运行。

提示：通知被点击或取消时调用方法stopSelf()。

Answer 2

通过使用 onTaskRemoved() 重新启动服务设法解决了这个问题。

@Override
public void onTaskRemoved(Intent rootIntent) {
    Log.i(TAG, "onTaskRemoved()");

    Intent restartServiceIntent = new Intent(getApplicationContext(), this.getClass());
    restartServiceIntent.setPackage(getPackageName());

    PendingIntent restartServicePendingIntent = PendingIntent.getService(getApplicationContext(), 1, restartServiceIntent, PendingIntent.FLAG_ONE_SHOT);
    AlarmManager alarmService = (AlarmManager) getApplicationContext().getSystemService(Context.ALARM_SERVICE);
    alarmService.set(
            AlarmManager.ELAPSED_REALTIME,
            SystemClock.elapsedRealtime() + 1000,
            restartServicePendingIntent);

    super.onTaskRemoved(rootIntent);
}

应用程序关闭时未触发通知

Notification not triggered when app is closed

android

alarmmanager

android-intent

android-service

android-notifications