(安卓)AlarmManager似乎不工作

它目前设置为5分钟后响,我在某个地方读到这是最短的时间,不确定这是不是真的。

完整的源代码,我已经上传到项目 github .

下面是片段:

public class TaskFragment extends Fragment {
...
 @Override
    public void onPause() {
        super.onPause();

        Intent intent = new Intent(getContext(), AlarmReceiver.class);
        intent.putExtra("time", mTask.getReminder().getTime());

        PendingIntent alarmIntent = PendingIntent.getBroadcast(getContext(), 10, intent, 0);

        AlarmManager alarmManager = (AlarmManager) getContext().getSystemService(getContext().ALARM_SERVICE);
        alarmManager.set(AlarmManager.ELAPSED_REALTIME_WAKEUP, SystemClock.elapsedRealtime() + 5 * 60 * 1000, alarmIntent);

        Log.i("Pending AlarmIntent", "Created");

以下是测试AlarmReceiver:

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.media.Ringtone;
import android.media.RingtoneManager;
import android.net.Uri;
import android.util.Log;

import java.util.Date;

/**
 * Created by rmatos on 12/08/17.
 */

public class AlarmReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(final Context context, Intent intent) {
        Uri uri = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_ALARM);
        Ringtone ringtone = RingtoneManager.getRingtone(context, uri);
        ringtone.play();
}
}

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="com.example.rmatos.simpletodo">

<uses-permission android:name="com.android.alarm.permission.SET_ALARM" />
<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED"/>                     <!-- TODO: Implement alarm manager that works when phone restarted -->

<application
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:roundIcon="@mipmap/ic_launcher_round"
    android:supportsRtl="true"
    android:theme="@style/AppTheme">

    <activity android:name=".TaskListActivity">
        <intent-filter>
            <action android:name="android.intent.action.MAIN"/>

            <category android:name="android.intent.category.LAUNCHER"/>
        </intent-filter>
    </activity>

    <activity
        android:name=".TaskPagerActivity"
        android:parentActivityName=".TaskListActivity">
        <intent-filter>
            <action android:name="android.intent.action.SET_ALARM" />
            <category android:name="android.intent.category.DEFAULT" />
        </intent-filter>

        <receiver
            android:process=":remote"
            android:name=".AlarmReceiver"
            android:enabled="true"
            android:exported="true"/>
    </activity>


</application>