setstate/ update data flutter

Question

So i have one page with a appbar and a body (gridview). In my appbar i have one button, that button show me a showModalBottomSheet and there i have one button to save the selected item. Exemple:

enter image description here

I need refresh my gridview when i click the button "Guardar", so i have to pass da value selected from showModalBottomSheet to gridview. i think i do that but dont kwon how i refresh the screen.

ty

Gridview

class PostsList extends StatefulWidget {
  String num;
  int startIndex;
  int postLimit;
  String atrib;
  PostsList(
      {Key? key,
      required this.num,
      required this.startIndex,
      required this.postLimit,
      required this.atrib})
      : super(key: key);

  @override
  State<PostsList> createState() =>
      _PostsListState(num, startIndex, postLimit, atrib);
}

class _PostsListState extends State<PostsList> {
  String num;
  int startIndex;
  int postLimit;
  String atrib;
  _PostsListState(this.num, this.startIndex, this.postLimit, this.atrib);

  final _scrollController = ScrollController();

  @override
  void initState() {
    super.initState();
    _scrollController.addListener(_onScroll);
  }
  

  @override
  Widget build(BuildContext context) {
    return BlocProvider(
      create: (_) => PostBloc(RepositoryProvider.of<PostRepository>(context),
          num, startIndex, postLimit, atrib)
        ..add(PostFetched()),
      child: BlocBuilder<PostBloc, PostState>(
        builder: (context, state) {
          switch (state.status) {
            case PostStatus.failure:
              return const Center(child: Text('Falha ao carregar produtos'));
            case PostStatus.success:
              if (state.posts.isEmpty) {
                return const Center(child: Text('Lista de produtos vazia'));
              }
              return Column(
                children: [
                  Expanded(
                    child: Container(
                      padding: const EdgeInsets.fromLTRB(3, 0, 0, 0),
                      color: Colors.grey[350],
                      child: GridView.builder(
                        gridDelegate:
                            const SliverGridDelegateWithFixedCrossAxisCount(
                                crossAxisCount: 2,
                                mainAxisSpacing: 5,
                                crossAxisSpacing: 5,
                                childAspectRatio: 0.55),
                        itemCount: state.hasReachedMax
                            ? state.posts.length
                            : state.posts.length + 2,
                        controller: _scrollController,
                        itemBuilder: (BuildContext context, int index) {
                          if (state.posts[index].quantity > 0) {
                            return index >= state.posts.length
                                ? const BottomLoader()
                                : PostListItemdisp(post: state.posts[index]);
                          } else {
                            return index >= state.posts.length
                                ? const BottomLoader()
                                : PostListItemIndisp(post: state.posts[index]);
                          }
                        },
                      ),
                    ),
                  ),
                ],
              );
            case PostStatus.initial:
              return const Center(child: CircularProgressIndicator());
          }
        },
      ),
    );
  }

  @override
  void dispose() {
    _scrollController
      ..removeListener(_onScroll)
      ..dispose();
    super.dispose();
  }

  void _onScroll() {
    if (_isBottom) context.read<PostBloc>().add(PostFetched());
  }

  bool get _isBottom {
    if (!_scrollController.hasClients) return false;
    final maxScroll = _scrollController.position.maxScrollExtent;
    final currentScroll = _scrollController.offset;

    return currentScroll >= (maxScroll * 0.8);
  }
} 

BOTTOMSHEET

const List<Widget> opcoes = <Widget>[
  Text('Referencia'),
  Text('Preço'),
  Text('Nome'),
  Text('Quantidade'),
];

class teste extends StatefulWidget {
  String num;
  int startIndex;
  int postLimit;

  teste({
    Key? key,
    required this.num,
    required this.startIndex,
    required this.postLimit,
  }) : super(key: key);

  @override
  State<teste> createState() => _testeState(num, startIndex, postLimit);
}

class _testeState extends State<teste> {
  String num;
  int startIndex;
  int postLimit;

  _testeState(this.num, this.startIndex, this.postLimit);

  final List<bool> _selectedOpcoes = <bool>[true, false, false, false];

  final List<String> _selectedTexto = <String>[
    'Reference',
    'Price',
    'Name',
    'Quantity'
  ];

  bool vertical = false;

  String finalTexto = 'Reference';
  @override
  Widget build(BuildContext context) {
    return ListView(
      children: [
        Padding(
          padding: const EdgeInsets.only(
            bottom: 10,
            left: 270,
            right: 10,
            top: 10,
          ),
          child: ElevatedButton(
            onPressed: () {
              PostsList(
                num: num,
                startIndex: startIndex,
                postLimit: postLimit,
                atrib: finalTexto,
              );
            },
            child: const Text('Guardar', style: TextStyle(fontSize: 18)),
          ),
        ),
        const SizedBox(
          height: 70,
        ),
        const Padding(
          padding: EdgeInsets.symmetric(horizontal: 20),
          child: Text(
            'Ordenar por:',
            style: TextStyle(
                fontSize: 18, color: Colors.black, fontWeight: FontWeight.bold),
          ),
        ),
        const SizedBox(
          height: 10,
        ),
        Padding(
          padding: const EdgeInsets.symmetric(horizontal: 30),
          child: ToggleButtons(
            direction: vertical ? Axis.vertical : Axis.horizontal,
            onPressed: (int index) {
              setState(() {
                for (int i = 0; i < _selectedOpcoes.length; i++) {
                  _selectedOpcoes[i] = i == index;
                  if (_selectedOpcoes[i] == true) {
                    finalTexto = _selectedTexto[i];
                  }
                }
              });
            },
            borderRadius: const BorderRadius.all(Radius.circular(8)),
            selectedBorderColor: primeColor,
            selectedColor: primeColor,
            fillColor: Colors.white,
            color: Colors.black,
            constraints: const BoxConstraints(
              minHeight: 40.0,
              minWidth: 80.0,
            ),
            isSelected: _selectedOpcoes,
            children: opcoes,
          ),
        ),
      ],
    );
  }
}

Answer 1

Rafael, you can use a callback function for this:

In your PostsList:

updateGrid(){
   setState(() => {
     
   });
}

/// When button FILTROS is clicked:

MyBottomSheetWidget(updateGrid: updateGrid);

And in your BottomSheetWidget:

  String num;
  int startIndex;
  int postLimit;
  final Function() updateGrid;

  teste({
    Key? key,
    required this.num,
    required this.startIndex,
    required this.postLimit,
    required this.updateGrid,
  }) : super(key: key);

/// when GUARDAR is clicked

widget.updateGrid();

So... when the Guardar button perform an action the function updateGrid will be called inside PostList widget.