flutter- data is not refreshing in stream builder when a condition update in firestore query

Question

I am facing problem in using stream builder. Actually, I have a dropdown list and below it I have gridview to show product categories according to options chose in dropdown list. I have to use two stream builders, one for option(s) list in dropdown and other is for gridview. Dropdown is wroking fine but gridview is not changing data according to option choose in dropdown list. Please help

My dropdown widget

Widget dropDownMenu({
required Size size,
BuildContext? context,}) {
return StatefulBuilder(builder: (context, setState) {
  return FutureBuilder(
    future: FirebaseFirestore.instance
        .collection('options').get(),
    builder: (BuildContext context, AsyncSnapshot snapshot) {
      if (snapshot.hasError) {
        return Center(child: Text('Error while loading'));
      }
      if (snapshot.connectionState == ConnectionState.waiting) {
        return Center(
          child: SpinKitFadingCircle(
            itemBuilder: (BuildContext context, int index) {
              return DecoratedBox(
                decoration: BoxDecoration(
                  color: index.isEven
                      ? MyStyles.themeData().primaryColor
                      : Colors.green,
                ),
              );
            },
          ),
        );
      }
      if (snapshot.hasData && snapshot.data!.docs.isEmpty) {
        return Center(child: Text('No Data'));
      }
      return Container(
        height: size.height * 0.100,
        padding: EdgeInsets.all(20.0),
        color: Colors.white,
        child: DropdownButton<String>(
            dropdownColor: Colors.white,
            elevation: 1,
            value: viewModel.dropDownValue!,
            hint: Text('Choose one option'),
            items:
                snapshot.data!.docs.map<DropdownMenuItem<String>>((value) {
              return DropdownMenuItem<String>(
                value: value.get('options'),
                child: Text(
                  value.get('options'),
                  overflow: TextOverflow.ellipsis,
                  textAlign: TextAlign.center,
                  style: GoogleFonts.poppins(
                    color: MyStyles.themeData().primaryColor,
                    fontSize: size.height * 0.024,
                    fontWeight: FontWeight.w600,
                  ),
                ),
              );
            }).toList(),
            onChanged: (value) {
              setState(() {
                viewModel.dropDownValue = value;
              });
            }),
      );
    },
  );
});}

My gridview Widget

  Widget buildGridView({Size? size, BuildContext? context}) {
return Expanded(
  child: Padding(
    padding: const EdgeInsets.symmetric(horizontal: 10.0),
    child: StreamBuilder<QuerySnapshot>(
      stream: FirebaseFirestore.instance
          .collection('categories')
          .where('options', isEqualTo: viewModel.dropDownValue)
          .snapshots(),
      builder:
          (BuildContext context, AsyncSnapshot<QuerySnapshot> snapshot) {
        if (snapshot.hasError) {
          return Center(child: Text('Error while loading'));
        }
        if (snapshot.connectionState == ConnectionState.waiting) {
          return Center(
            child: SpinKitFadingCircle(
              itemBuilder: (BuildContext context, int index) {
                return DecoratedBox(
                  decoration: BoxDecoration(
                    color: index.isEven
                        ? MyStyles.themeData().primaryColor
                        : Colors.green,
                  ),
                );
              },
            ),
          );
        }
        if (snapshot.hasData && snapshot.data!.docs.isEmpty) {
          return Center(child: Text('No Categories available'));
        }
        return GridView.builder(
          padding: const EdgeInsets.only(bottom: 70),
          gridDelegate: SliverGridDelegateWithMaxCrossAxisExtent(
            maxCrossAxisExtent: 200,
            childAspectRatio: 1,
            crossAxisSpacing: 20,
            mainAxisSpacing: 20,
          ),
          itemCount: snapshot.data!.size,
          itemBuilder: (BuildContext ctx, index) {
            return GestureDetector(
              onTap: () {},
              child: Container(
                margin: const EdgeInsets.symmetric(horizontal: 3.0),
                height: size!.height * 0.200,
                width: double.infinity,
                alignment: Alignment.center,
                decoration: BoxDecoration(
                  color: Colors.white,
                  borderRadius: BorderRadius.circular(15),
                  boxShadow: [
                    BoxShadow(
                      color: Color(0x99C4C4C4),
                      blurRadius: 12,
                      offset: Offset(4, 4),
                      spreadRadius: 0,
                    ),
                  ],
                ),
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.center,
                  mainAxisAlignment: MainAxisAlignment.center,
                  children: [
                    Container(
                        height: size.height * 0.120,
                        width: size.width * 0.120,
                        child: Image.network(
                            snapshot.data!.docs[index]['image'])),
                    SizedBox(height: size.height * 0.015),
                    Text(
                      snapshot.data!.docs[index]['name']!,
                      textAlign: TextAlign.center,
                      overflow: TextOverflow.ellipsis,
                      style: GoogleFonts.poppins(
                        color: MyStyles.themeMode().textColor,
                        fontSize: size.height * 0.022,
                        fontWeight: FontWeight.w500,
                      ),
                    ),
                  ],
                ),
              ),
            );
          },
        );
      },
    ),
  ),
);}

I want to rebuild stream everytime I change options in dropdown. How can I achieve this?