How to Make Checkbox Dynamically retrieve data from Mysql?

I want to make checkbox flutter dynamically which retrieve data from database mysql. So, this code can display data from mysql. But still can’t check one by one. this my code :

    class TambahDataTanaman extends StatefulWidget {
      @override
      _TambahDataTanamanState createState() => _TambahDataTanamanState();
    }

    class _TambahDataTanamanState extends State<TambahDataTanaman> {
      GlobalKey<FormState> addTanamanKey = GlobalKey<FormState>();
     
      bool selected = false;
      Future<List> getData() async {
        final response =
            await http.get("http://192.168.1.9/tanampedia/tanahtampil.php");
        return json.decode(response.body);
      }

      List selectedData = [];


      @override


      Widget build(BuildContext context) {
        return Scaffold(
            appBar: AppBar(
              title: Text("Tambah Data Tanaman"),
              backgroundColor: Colors.green,
            ),
            body: SingleChildScrollView(
              child: Form(
                key: addTanamanKey,
                child: Padding(
                  padding: const EdgeInsets.all(10.0),
                  child: ListView(
                    shrinkWrap: true,
                    children: [
                      new Column(
                        children: [
                          new FutureBuilder<dynamic>(
                              future: getData(),
                              builder: (context, snapshot) {
                                if (snapshot.hasError) print(snapshot.error);
                                return snapshot.hasData
                                    ? ListView.builder(
                                        shrinkWrap: true,
                                        itemCount: snapshot.data.length,
                                        itemBuilder: (context, index) {
                                          //List list = snapshot.data;
                                          return CheckboxListTile(
                                            title:
                                                Text(snapshot.data[index]['nama']),
                                            value: selected,
                                            onChanged: (bool newSelected) {
                                              setState(() {
                                                selected = newSelected;
                                              });
                                            },
                                            dense: true,
                                          );
                                        })
                                    : new Center(
                                        child: new CircularProgressIndicator());
                              }),

                         
                          new RaisedButton(
                              child: new Text(
                                "Tambah Data",
                                style: TextStyle(color: Colors.white),
                              ),
                              color: Colors.green,
                              onPressed: () {}),
                        ],
                      ),
                    ],
                  ),
                ),
              ),
            ));
      }
    }

I use future builder to make list for my checkboxlist. But when running the code, The result of the code above is that all values ​​are checked at the same time, so how to make them correct?