Flutter setState is not refresh page rightly

I'm using Flutter to build an app which has a post page with categories. But when I change the categories and setState to refresh the page, it is not working! Some of the posts are not refreshing but someones refresh. I need to route another page and then come back to the Post page to change all posts. So initState is refreshing my page but setState is not. I have nothing inside my initState of Post page.

It's my method that creates posts. It works very well. I have this method for my all categories which have another where method.

Firestore.instance
        .collection("posts")
        .where("likers", arrayContains: Constants.firebaseUser.uid)
        .orderBy("id", descending: true)
        .getDocuments()
        .then((value) => Constants.productsForOwn = value.documents
            .map((documentSnapshot) =>
                Product.fromDocument(documentSnapshot, Constants.position))
            .toList());

Then that is the problem, posts page;

           ListView.builder(
                controller: controller,
                itemCount: Constants.products.length + 1,
                itemBuilder: (context, index) {
                  if (index == 0) {
                    // return the header
                    return Container(
                      height: MediaQuery.of(context).size.height / 6,
                      width: MediaQuery.of(context).size.width,
                      color: Colors.white,
                      child: Padding(
                        padding: const EdgeInsets.all(8.0),
                        child: ListView(
                          scrollDirection: Axis.horizontal,
                          children: [
                            category(Colors.grey, 'Her Şey',
                                Icon(Icons.accessibility), 0, 'productName1'),
                            category(
                                Colors.red,
                                'Süt Ürünleri',
                                Icon(Icons.accessibility),
                                1,
                                'productname2'),
                          
                          ],
                        ),
                      ),
                    );
                  } else (Constants.products.length >= index) {
                    return Constants.products[index - 1]; //creating posts
                  } 
                },
              )

All of my categories have a gesture detector and setState within;

 Widget category(
      Color color, String title, Icon icon, int index, String productType) {
    return Padding(
      padding: const EdgeInsets.symmetric(horizontal: 6.0),
      child: Container(
          child: GestureDetector(
        onTap: () async {
          Constants.indexOfPicked = index;


          Constants.searchingProductType = productType; 


          await Datas().assignAllPosts();     //that reassign the posts
         
          setState(() {});
        },
        child: Column(
          children: [
            Expanded(
              flex: 4,
              child: AspectRatio(
                  aspectRatio: 1,
                  child: Container(
                    decoration: BoxDecoration(
                        border: Border.all(
                            color: (Constants.indexOfPicked == index)
                                ? Colors.green
                                : Colors.transparent,
                            width: 2),
                        color: color,
                        borderRadius: BorderRadius.circular(12)),
                  )),
            ),
          
          ],
        ),
      )),
    );
  }
}