How to access scrollviewcontroller from another page in flutter?

I am a newbie at Flutter. I am making a website for publishing. I am trying to jumpto my page using SingleChildScrollView’s controller. I have a custom app bar. And The custom app bar has 4 buttons. But the problem is: The custom app bar is in different page. My purpose is: When I click the this buttons. My SingleChildScrollView jumps to the point. I can not move it without using same page. But I want to use it at different page.

Here is my code: ( Custom app bar page )

import 'package:flutter/material.dart';

class TopBarContents extends StatefulWidget {

  TopBarContents();

  @override
  _TopBarContentsState createState() => _TopBarContentsState();
}

class _TopBarContentsState extends State<TopBarContents> {
  final List _isHovering = [
    false,
    false,
    false,
    false,
    false,
    false,
    false,
    false
  ];
  static int _counter = 0;
  @override
  Widget build(BuildContext context) {
    double width = MediaQuery.of(context).size.width;
    double height = MediaQuery.of(context).size.height;

    var screenSize = MediaQuery.of(context).size;




    ScrollController scrollController = ScrollController();


    void _scroller() {

      setState(() {
        // This call to setState tells the Flutter framework that something has
        // changed in this State, which causes it to rerun the build method below
        // so that the display can reflect the updated values. If we changed
        // _counter without calling setState(), then the build method would not be
        // called again, and so nothing would appear to happen.



       
        //  final double start = 0;
        // final double start = 1350;
        final double start = 4050;

        scrollController.jumpTo(start);

        //  scrollController.animateTo(start, duration: Duration(seconds: 1), curve: Curves.easeIn);

      });
    }


    return Container(
      color: Colors.white.withOpacity(0.5),
      child: Padding(
        padding: EdgeInsets.all(20),
        child:
        Expanded(
          child: Row(
            mainAxisAlignment: MainAxisAlignment.start,
            children: [
              SizedBox(width: screenSize.width/6,),

          Image.asset("images/logo_hesap.png", width: width/10,),

      
              SizedBox(width: screenSize.width / 15),
              InkWell(
                onHover: (value) {
                  setState(() {
                    value
                        ? _isHovering[0] = true
                        : _isHovering[0] = false;
                  });
                },
                onTap: () {


                  _scroller();
                 
                 
                  final double start = 4050;

                  scrollController.jumpTo(start);



                },
                child: Column(
                  mainAxisSize: MainAxisSize.min,
                  children: [
                    Text(
                      'Ana Sayfa',
                      style: TextStyle(
                          color: _isHovering[0]
                              ? Color(0xff000000)
                              : Color(0xff32b146),
                          fontWeight: FontWeight.bold,
                          fontSize: 16
                      ),
                    ),

The main page: ( The page has only scrollview and other widgets)

SingleChildScrollView(
              controller: scrollController,)