FutureBuilder(
              future: doesNameAlreadyExist(Controller.text),
              builder: (context, AsyncSnapshot<bool> result) {
                if (!result.hasData)
                  return Container(); // future still needs to be finished (loading)
                if (result
                    .data) { // result.data is the returned bool from doesNameAlreadyExists
                  return Text("Your ID exists",style: TextStyle(color: Colors.green),);
                }
                else
                  return Text("Your ID does not exist",style: new TextStyle(color: Colors.red),);
              },
            ),