Keep variable value even after multiple page routes unless changed in flutter - flutter

Question

I have a drawer widget with many Menu items. I have a variable that takes care of the selected item number. I initiate that with 1 to select the first item on load. When I select another MenuItem the value changes to the corresponding item number. When I redirect/reroute to the drawer page from the Menuitem page it again shows the first Menuitem. I want the variable value to remain and show the menu item which I had selected.
import 'package:country_code_picker/country_localizations.dart';
import 'package:flutter/material.dart';
import 'package:scoped_model/scoped_model.dart';
import 'package:wyiin_admin_portal/admin_screens/access_management.dart';
import 'package:wyiin_admin_portal/admin_screens/brand_management_main.dart';
import 'package:wyiin_admin_portal/admin_screens/language_management_main.dart';
import 'package:wyiin_admin_portal/admin_screens/product_category_management_main.dart';
import 'package:wyiin_admin_portal/admin_screens/promotion_management_main.dart';
import 'package:wyiin_admin_portal/login/password_reset.dart';
import 'package:wyiin_admin_portal/model/BrandMgmtScreens.dart';
import 'package:wyiin_admin_portal/work_in_progress.dart';
class MyAppDrawer extends StatelessWidget {
final appTitle = 'WYIIN';
#override
Widget build(BuildContext context) {
return MaterialApp(
supportedLocales: [
const Locale('en', 'US'),
],
debugShowCheckedModeBanner: false,
localizationsDelegates: [CountryLocalizations.delegate],
title: appTitle,
home: MyDrawer(title: appTitle),
theme: ThemeData(primaryColor: Color.fromRGBO(255, 255, 255, 1)),
);
}
}
class MyDrawer extends StatefulWidget {
final String title;
final int destination;
MyDrawer({Key key, this.title, this.destination}) : super(key: key);
#override
_MyHomePageState createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyDrawer> {
var _selectedDestination;
#override
Widget build(BuildContext context) {
print(_selectedDestination);
setState(() {
_selectedDestination =
_selectedDestination == null ? 1 : _selectedDestination;
});
print(_selectedDestination);
return ScopedModelDescendant<Screen>(builder: (_, child, model) {
return Row(
children: [
Container(
width: 255,
child: Drawer(
child: Container(
color: Color.fromRGBO(42, 48, 66, 1),
child: ListView(
padding: EdgeInsets.zero,
children: <Widget>[
Padding(
padding: const EdgeInsets.all(16.0),
child: Text('WYiiN',
style: TextStyle(
fontSize: 18,
fontWeight: FontWeight.bold,
color: Colors.white)),
),
Padding(
padding: const EdgeInsets.only(left: 15, top: 4),
child: Text('Menu',
style: TextStyle(
fontSize: 14,
fontWeight: FontWeight.w600,
color: Color.fromRGBO(106, 113, 135, 1))),
),
ListTile(
visualDensity: VisualDensity(horizontal: -4, vertical: 0),
contentPadding: const EdgeInsets.only(left: 15, top: 4),
leading: _selectedDestination == 6
? Image.asset(
'assets/images/Brand Management_active.png')
: Image.asset('assets/images/Brand Management.png'),
title: Text('Brand management',
style: TextStyle(
fontSize: 13,
fontWeight: FontWeight.w300,
color: _selectedDestination == 6
? Colors.white
: Color.fromRGBO(106, 113, 135, 1),
)),
selected: _selectedDestination == 6,
onTap: () {
if (model.showScreen == true) {
model.screenDecide();
}
selectDestination(6);
},
),
ListTile(
visualDensity:
VisualDensity(horizontal: -4, vertical: 0),
contentPadding: const EdgeInsets.only(left: 15, top: 4),
leading: _selectedDestination == 8
? Image.asset(
'assets/images/product_category_management_active.png')
: Image.asset(
'assets/images/product_category_management.png'),
title: Text('Product Category management',
style: TextStyle(
fontSize: 13,
fontWeight: FontWeight.w300,
color: _selectedDestination == 8
? Colors.white
: Color.fromRGBO(106, 113, 135, 1),
)),
selected: _selectedDestination == 8,
onTap: () {
if (model.showProdCatScreen == true) {
model.screenDecideProdCat();
}
selectDestination(8);
}),
ListTile(
visualDensity:
VisualDensity(horizontal: -4, vertical: 0),
contentPadding: const EdgeInsets.only(left: 15, top: 4),
leading: _selectedDestination == 9
? Image.asset(
'assets/images/language_management_active.png')
: Image.asset(
'assets/images/language_management.png'),
title: Text('Language Management',
style: TextStyle(
fontSize: 13,
fontWeight: FontWeight.w300,
color: _selectedDestination == 9
? Colors.white
: Color.fromRGBO(106, 113, 135, 1),
)),
selected: _selectedDestination == 9,
onTap: () {
if (model.showLangMgmtScreen == true) {
model.screenDecideLangMgmt();
}
selectDestination(9);
}),
],
),
),
),
),
VerticalDivider(
width: 1,
thickness: 1,
),
Expanded(
child: Scaffold(
body: _selectedDestination == 6
? BrandMgmtMain()
: _selectedDestination == 9
? LanguageMgmtMain()
: _selectedDestination == 7
? AccessMgmt()
: _selectedDestination == 8
? ProdCatMgmtMain()
: _selectedDestination == 5
? PromotionMgmtMain()
: _selectedDestination == 2
? WorkInProgress()
: _selectedDestination == 10
? PassReset()
: _selectedDestination == 1
? WorkInProgress()
: WorkInProgress()),
),
],
);
});
}
void selectDestination(int index) {
setState(() {
_selectedDestination = index;
print(_selectedDestination);
});
}
}
void body(int selection) {}