How to use the @ionic-native/code-push.SyncStatus.UP_TO_DATE function in @ionic-native/code-push

}).subscribe((syncStatus) => {

            if (syncStatus === SyncStatus.UP_TO_DATE) {

                // facing some zoning problems here !!
                // why ??

                // forcing to run in the ngzone
                this.ngZone.run(() => {
                    this.messageText = '应用程式是最新的！';
                });
            }

            // not facing zoning issue here ?

            switch (syncStatus) {
                case SyncStatus.IN_PROGRESS:
                    this.messageText = '正在进行更新 ..';
                    break;

.subscribe((syncStatus) => {
        switch (syncStatus) {
          case SyncStatus.CHECKING_FOR_UPDATE:
            notificationObject.text = "Checking for updates..."
            this.localNotifications.schedule(notificationObject);
            break;
          case SyncStatus.INSTALLING_UPDATE:
            notificationObject.text = "Installing update...";
            notificationObject["progressBar"] = { value: 100 };
            this.localNotifications.update(notificationObject);
            break;
          case SyncStatus.UP_TO_DATE:
          case SyncStatus.ERROR:
          case SyncStatus.UPDATE_IGNORED:
          case SyncStatus.UPDATE_INSTALLED:
            this.localNotifications.cancel(notificationObject.id);
            break;
        }
      });
  }