如何在颤振中使用提供程序或值通知程序将数据从子小部件传递到父小部件

问题描述

这是我的父小部件。

class AddUserextends StatefulWidget {
  final ScrollController controller;
  AddUser(this.controller);

  @override
  _AddUser createState() =>
      _AddUser();
}

class _AddUserToManagePropertyState extends State<AddUserToManageProperty> {
  late TextEditingController _firstNameCtrl;
  late TextEditingController _lastNameCtrl;
  late TextEditingController _phoneNoCtrl;
  late ValueNotifier<num?> _category;


  final _scaffoldKey = GlobalKey<ScaffoldState>();
  final _formKey = GlobalKey<FormState>();

  final ValueNotifier<bool> _formStateEmitter = ValueNotifier(false);
  final ValueNotifier<bool> isSelected = ValueNotifier(false);

  @override
  void initState() {
    super.initState();
    _firstNameCtrl = TextEditingController(text: '');
    _lastNameCtrl = TextEditingController(text: '');
    _phoneNoCtrl = TextEditingController(text: '');

    _firstNameCtrl.addListener(() {
      _formStateEmitter.value = _fieldsstatus();
    });
    _lastNameCtrl.addListener(() {
      _formStateEmitter.value = _fieldsstatus();
    });
    _phoneNoCtrl.addListener(() {
      _formStateEmitter.value = _fieldsstatus();
    });

  }

  bool _fieldsstatus() {
    return HwValidators.required(_firstNameCtrl.text) == null &&
        HwValidators.required(_lastNameCtrl.text) == null &&
        HwValidators.required(_phoneNoCtrl.text) == null;
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      key: _scaffoldKey,appBar: HwAppBar(
        title: 'Add team member',),body: Form(
        key: _formKey,child: FormWidget(
          maintainSafeArea: false,showBackBtn: false,fields: [
            HwTextField(
              label: 'FirsT NAME',controller: _firstNameCtrl,validator: HwValidators.nameValidator,keyboardType: TextInputType.text,HwSizedBox(height: 4),HwTextField(
              label: 'LAST NAME',controller: _lastNameCtrl,HwTextField(
              label: 'PHONE NO',controller: _phoneNoCtrl,validator: HwValidators.phoneValidator,keyboardType: TextInputType.phone,HwText('ACCESS LEVEL'),UserAccessListTiles(),HwSizedBox(
              height: 4,],);
  }
}

倒数第二个小部件是 UserAccessListTiles，这是一个小部件，允许用户从两组小部件中进行选择，如下所示：

class UserAccessListTiles extends StatelessWidget {
  List _userAccessListTile = [
    SelectableTile(
      title: 'Access to all stories',leading: SvgPicture.asset(HwSvgs.fullAccess),trailing: null,SelectableTile(
        title: 'Custom access',leading: SvgPicture.asset(HwSvgs.customAccess),trailing: null),];

  final ValueNotifier<int> _selected = ValueNotifier(0);

  @override
  Widget build(BuildContext context) {
    return ValueListenableBuilder(
        valueListenable: _selected,builder: (context,int value,child) {
          return Column(
            children: [
              Container(
                child: ListView.builder(
                  shrinkWrap: true,physics: NeverScrollableScrollPhysics(),itemCount: 2,itemBuilder: (context,index) {
                    return Column(
                      children: [
                        HwSizedBox(
                          height: 3,InkWell(
                          onTap: () {
                            _selected.value = index;
                          },child: Container(
                            decoration: Boxdecoration(
                                border: Border.all(
                                  width: value == index ? 2 : 1,color: value == index
                                      ? HwColors.green
                                      : HwColors.divider,borderRadius: BorderRadius.circular(8.0)),child: SelectableTile(
                              title: _userAccessListTile[index].title,leading: _userAccessListTile[index].leading,trailing: value == index
                                  ? SvgPicture.asset(HwSvgs.greenCheck)
                                  : null,);
                  },_selected.value == 0 ? UserAccessListTilesRadio() : CustomAccess(),);
        });
  }
}

最后，这两个小部件 UserAccessListTilesRadio() 和 CustomAccess() 都有一组 RadioListTile 可供用户选择，我希望所选的选项作为表单的一部分在原始父小部件中可用。

我该怎么做，请帮忙。

解决方法

我建议您使用状态管理，即 Bloc 或 Provider

例如提供者 制作一个 extends ChangeNotifierProvider

的模型

class MyProviderModel extends ChangeNotifierProvider{
int yourChosenValue;

 void updateChosenValue() {
   // Your logic
   notifyListeners();
 }
}

在您的父小部件中初始化提供程序

Provider(
  create: (_) => MyProviderModel(),child: Consumer<MyProviderModel>(
   builder: (_,a,child) {
      return // Your Form
    },)
)

在您的子小部件中更新您的 MyProviderModel

context.read<MyProviderModel>().updateChosenValue();

在你的父 Widget 中初始化 Provider