如何更改 CheckBoxListTile 中的值项？

Question

I am trying to update the check of the CheckBoxListTile but I am not getting the desired result.

This is my code:

Widget build(BuildContext context) {
    return Query(
      options: QueryOptions(document: getVehiclesTypeQueryDoc),
      builder: (result, {fetchMore, refetch}) {
        if (result.isLoading && result.data == null) {
          return Center(
            child: CircularProgressIndicator(),
          );
        }
        newVehiclesType = [];
        final _vehiclesTypeJson = result.data['tipoVehiculos'] as List<dynamic>;
        for (final i in _vehiclesTypeJson) {
          var productMap = {
            'id': i['id'],
            'nombre': i['nombre'],
            'imagenActivo': i['imagenActivo'],
            'isSelected': true
          };
          newVehiclesType.add(productMap);
        }
        final List<dynamic> test = newVehiclesType;
        print('test: $test');
        return ListView.builder(
          itemCount: test.length,
          shrinkWrap: true,
          itemBuilder: (context, index) {
            print(index);
            print('VALO: ${test[index]['isSelected']}');
            return CheckboxListTile(
              title: Text(test[index]['nombre'].toString()),
              value: test[index]['isSelected'],
              onChanged: (bool newValue) {
                setState(() {
                  test[index]['isSelected'] = newValue;
                });
              },
            );
          },
        );
      },
    );
  }

I created a newVehiclesType variable, the query did not give me a variable to use the check for.

I am new to flutter.

Answer 1

this is the code that i use in my application hopefully hopefully it will help you

value: isCheckedEdit.contains(_ingredientList[index].nameIngredient),
                              onChanged: (value) {
                                if (value) {
                                  setState(() {
                                    isCheckedEdit
                                        .add(_ingredientList[index].nameIngredient);
                                    print(isCheckedEdit);
                                  });
                                } else {
                                  setState(() {
                                    isCheckedEdit.remove(
                                        _ingredientList[index].nameIngredient);
                                    print(isCheckedEdit);
                                  });
                                }
                              },
                            );

Answer 2

Angular has an amazing documentation that teaches every concept in detail (60%). I highly recommend you to visit the the documentation site. There are examples and explanations for each topic.

https://angular.io/guide/reactive-forms

Thank you so much for bringing such a beautiful question up. Angular is love.

Answer 3

class VehiclesList extends StatefulWidget {
  @override
  _VehiclesListState createState() => _VehiclesListState();
}

class _VehiclesListState extends State<VehiclesList> {
  List<dynamic> test;

  @override
  Widget build(BuildContext context) {
    // your code

    // when result has data, instead of 
    // final List<dynamic> test = newVehiclesType;

    // do this
    test = newVehiclesType;
  }
}

What this basically does is, it uses test to hold the widget state. In your code, test is local to your build function and would be reinitialized as many times build function runs.

This way it would not reinitialize on widget rebuilds when setState() is called.