当应用在后台被杀死并且设备被锁定时，警报管理器将无法工作 [英] Alarm Manager won't work when the app is killed in the background and device is locked

问题描述

我在这种情况下已经停留了很长时间...

I have been stuck in this situation for a long time...

我想使用警报管理器在特定时间显示通知，现在在以下情况下正常工作：

I want to use the alarm manager to show notification at the specific time, and now it worked in the situation listed below:

1. 当应用在后台运行时，通知将在正确的时间显示，无论设备是否已锁定。


2. 应用程序在后台被杀死后，当设备未锁定时，我仍会收到正确的通知，但是当设备锁定时，事情会出错。无法接收任何通知。

这是代码AlarmReceiver.java，所有必需的权限已添加到AndroidManifest.xml中：

Here's the code AlarmReceiver.java, all the needed permission has been added into AndroidManifest.xml already:

@Override
public void onReceive(Context context, Intent intent) {
    WakeLocker.acquire(context);

    String action = intent.getAction();

    Log.d(TAG, action); //when app is killed and device is locked, no info is shown at the logcat

    if (ACTION_ALARM.equals(action)) {
        Vibrator vibrator = (Vibrator) context.getSystemService(Context.VIBRATOR_SERVICE);
        vibrator.vibrate(2 * 1000);

        notify(context, "Jello!");
    }

    WakeLocker.release();
}

public static void alarm(Context context) {
    AlarmManager alarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
    Intent intent = new Intent(context, AlarmReceiver.class);
    intent.setAction(ACTION_ALARM);
    PendingIntent pi = PendingIntent.getBroadcast(context, 0, intent, 0);

    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
        alarmManager.setExact(AlarmManager.ELAPSED_REALTIME_WAKEUP, SystemClock.elapsedRealtime() + 5 * 1000, pi);
    } else {
        alarmManager.set(AlarmManager.ELAPSED_REALTIME_WAKEUP, SystemClock.elapsedRealtime() + 5 * 1000, pi);
    }
}

private void notify(Context context, String msg) {
    NotificationManager notificationManager = (NotificationManager)
            context.getSystemService(Context.NOTIFICATION_SERVICE);

    PendingIntent contentIntent = PendingIntent.getActivity(context, 0,
            new Intent(context, InfoActivity.class), 0);

    Notification notification =
            new NotificationCompat.Builder(context)
                    .setSmallIcon(R.mipmap.ic_launcher)
                    .setContentTitle(context.getString(R.string.alarm))
                    .setStyle(new NotificationCompat.BigTextStyle().bigText(msg))
                    .setContentText(msg)
                    .setAutoCancel(true)
                    .setContentIntent(contentIntent).build();

    notificationManager.notify(1, notification);
}

添加的权限：

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

推荐答案

我刚刚找到解决方案，将名为FLAG_INCLUDE_STOPPED_PACKAGES的标志设置为发出警报的意图，一切都会顺利进行。
这是 Android开发人员中的插图

I just found the solution, set flag named FLAG_INCLUDE_STOPPED_PACKAGES to intent of the alarm, things will go right. Here are the illustration in Android Developers

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