应用程式被杀死时，AlarmManager并非一直都在工作

Question

我在我的应用程序中使用AlarmManager。 当应用程序位于前台时，它始终有效，但是当应用程序被杀死时，它在大多数情况下不起作用（但有时可以工作）。

以下是设置警报的代码：

Intent intent = new Intent(context, AlarmService.class);
            intent.setAction(AlarmService.ACTION_SHOW_ALERTS);
            intent.putExtra(Constants.BundleKeys.ALERTS_ID,alert.getId());

            PendingIntent pendingIntent = PendingIntent.getService(context, alert.getAlertID(), intent, PendingIntent.FLAG_UPDATE_CURRENT);
            AlarmManager alarmManager = (AlarmManager) context.getSystemService(ALARM_SERVICE);

            if (Build.VERSION.SDK_INT >= 23)

                alarmManager.setExactAndAllowWhileIdle(AlarmManager.RTC_WAKEUP, alert.getId(), pendingIntent);
            else if (Build.VERSION.SDK_INT >= 19)

                alarmManager.setExact(AlarmManager.RTC_WAKEUP, alert.getId(), pendingIntent);
            else

                alarmManager.set(AlarmManager.RTC_WAKEUP, alert.getId(), pendingIntent);

我的AlarmService.java类：

public class AlarmService extends IntentService {

public AlarmService() {
    super("Alarm service");
}

@Override
public void onCreate() {
    super.onCreate();
}

@Override
protected void onHandleIntent(@Nullable Intent intent) {
    
    Intent alarm = new Intent(this, AlarmActivity.class);
    alarm.putExtra(BundleKeys.ALERTS_ID, alertId);
    alarm.putExtra(BundleKeys.IS_SNOOZED, snoozed);
    alarm.setFlags(FLAG_ACTIVITY_NEW_TASK);
    startActivity(alarm);
}}

我的AlarmActivity，在警报到达时间时显示：

public class AlarmActivity extends AppCompatActivity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    this.requestWindowFeature(Window.FEATURE_NO_TITLE);
    this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
            WindowManager.LayoutParams.FLAG_FULLSCREEN);
    // Turn the device's screen on and keep it turned on and bright
    // as long as this window is visible to the user
    getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON
            | WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON);
    setContentView(R.layout.activity_alarm);

    Long alertTime = getIntent().getLongExtra(BundleKeys.ALERTS_ID,0);
    boolean isSnoozed = getIntent().getBooleanExtra(BundleKeys.IS_SNOOZED, false);

    Fragment fragment = AlarmFragment.newInstance(alertTime, isSnoozed);
    FragmentUtils.addFragment(this, fragment, R.id.container);

    final Window win = getWindow();
    win.addFlags(WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED
            | WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD);
}

//DO not remove this method
@Override
public void onBackPressed() {
}}

我的清单：

<service android:name="AlarmService"/>

    <activity
        android:name="AlarmActivity"
        android:excludeFromRecents="true"
        android:launchMode="singleTask"
        android:screenOrientation="portrait"
        android:showOnLockScreen="true"></activity>

我究竟做错了什么？