小部件对实时变化没有反应 - Flutter

Question

在显示警报框时，我试图更改 saveButton 小部件的框阴影，它只是一个按钮。一旦填充 TextFormField，该按钮就会变为活动状态。但是，直到用户按下键盘上的 Done 或 Submit 后，该按钮才会变为活动或非活动状态。下面是为了更好地理解的视频和供参考的代码。

class AddFacilityEquipmentWidget extends StatelessWidget {
  final AddFacilityProvider provider;

  AddFacilityyEquipmentWidget({this.provider});

  @override
  Widget build(BuildContext context) {
    return equipmentTypesColumn(context);
  }

  Widget equipmentTypesColumn(BuildContext context) {
    return Column(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        Text(Translations.of(context).getEquipment),
        addCustomEquipmentButton(context),
      ],
    );
  }

  Widget addCustomEquipmentButton(BuildContext context) {
    return GestureDetector(
      onTap: () {
        showDialog(
          context: context,
          barrierDismissible: false,
          builder: (context) => addEquipmentAlertWidget(context),
        );
      },
      child: Text("Add Custom Equipment"),
    );
  }

  Widget addEquipmentAlertWidget(BuildContext context) {
    return AlertDialog(
      contentPadding: EdgeInsets.zero,
      content: Container(
        child: Column(
          children: <Widget>[
            upperTitleWidget(context),
            SizedBox(height: d_50),
            equipmentNameField(context),
            SizedBox(height: d_50),
            saveButton(context)
          ],
        ),
      ),
    );
  }

  Widget upperTitleWidget(BuildContext context) {
    return Row(
      mainAxisAlignment: MainAxisAlignment.spaceBetween,
      children: [
        Text(
          Translations.of(context).getAddEquipment,
          style: d18fw700Black,
        ),
        Container(
          height: d_20,
          width: d_20,
          child: IconButton(
              padding: pd_0,
              icon: Icon(
                Icons.cancel,
                color: greyColor,
              ),
              onPressed: () {
                provider.isAddEquipmentButtonActive = false;
                provider.addNewEquipmentController.clear();

                Navigator.pop(context);
              }),
        )
      ],
    );
  }

  Widget equipmentNameField(BuildContext context) {
    return Container(
      child: TextFormField(
        controller: provider.addNewEquipmentController,
        keyboardType: TextInputType.text,
        onChanged: (text) {
          if (text.length > 0) {
            provider.isAddEquipmentButtonActive = true;
          } else {
            provider.isAddEquipmentButtonActive = false;
          }
        },
      ),
    );
  }

  Widget saveButton(BuildContext context) {
    return GestureDetector(
      onTap: () {},
      child: Container(
        decoration: BoxDecoration(
            boxShadow: [
              provider.isAddEquipmentButtonActive
                  ? BoxShadow() //Box Shadow 1
                  : BoxShadow(), // Box Shadow 2
            ],
            color: provider.isAddEquipmentButtonActive
                ? backgroundColor
                : deactivatButtonColor,
            borderRadius: BorderRadius.circular(d_100)),
        child: Text(
          Translations.of(context).getAddEquipment,
        ),
      ),
    );
  }
}

编辑：下面是 AddFacilityProvider 类的代码

class AddFacilityProvider extends ChangeNotifier {
  List<Facilities> _equipmentList = [
    Facilities(text: "Floodlights", key: "Floodlights", isOpen: false),
    Facilities(text: "Scoreboard", key: "Scoreboard", isOpen: false),
    Facilities(text: "Changing rooms", key: "Changing rooms", isOpen: false),
    Facilities(text: "Showers", key: "Showers", isOpen: false),
    Facilities(text: "Free parking", key: "Free parking", isOpen: false),
    Facilities(
        text: "Wheelchair friendly", key: "Wheelchair friendly", isOpen: false),
    Facilities(text: "Drinking water", key: "Drinking water", isOpen: false),
    Facilities(text: "Sports bar", key: "Sports bar", isOpen: false),
    Facilities(text: "Toilets", key: "Toilets", isOpen: false),
  ];
  TextEditingController _addNewEquipmentController =
      TextEditingController();
  bool _isEnableAddNewFacilityEquipment = false;
  bool _isAddEquipmentButtonActive = false;
  

  void toggleAddEquipmentActive(bool value) {
    _isAddEquipmentButtonActive = value;
    notifyListeners();
  }

  TextEditingController get addNewEquipmentController =>
      _addNewEquipmentController;

  set addNewEquipmentController(TextEditingController value) {
    _addNewEquipmentController = value;
    notifyListeners();
  }

  bool get isEnableAddNewFacilityEquipment => _isEnableAddNewFacilityEquipment;

  set isEnableAddNewFacilityEquipment(bool value) {
    _isEnableAddNewFacilityEquipment = value;
    notifyListeners();
  }

  bool get isAddEquipmentButtonActive => _isAddEquipmentButtonActive;

  set isAddEquipmentButtonActive(bool value) {
    _isAddEquipmentButtonActive = value;
    notifyListeners();
  }
}