Persistent menu in nav (for Katekko)

main.dart

import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:get/get.dart';

void main() {
  runApp(GetMaterialApp(
    home: _MyHome(),
    builder: MyRootWidget.builder,
  ));
}

class _MyHome extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('page 1'),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            Text('Hello world'),
            FlatButton(
                onPressed: () => Get.to(_MySecondPage()),
                child: Text('To second page'))
          ],
        ),
      ),
    );
  }
}

class _MySecondPage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('second page'),
      ),
      body: Center(
        child: Text('Bye World!'),
      ),
    );
  }
}

/// custom utils.
///
class MyPersistentDrawer extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Container(
      width: 300,
      height: double.infinity,
      color: Colors.grey.shade600,
      padding: EdgeInsets.symmetric(vertical: 24, horizontal: 12),
      child: Column(
        children: [
          CircleAvatar(
            child: Icon(Icons.ac_unit),
          ),
          Text(
            'My drawer',
            style: TextStyle(
              fontSize: 24,
              color: Colors.white,
              fontWeight: FontWeight.bold,
            ),
          ),
          Divider(
            color: Colors.white10,
            height: 24,
          ),

          /// menu data here.
        ],
      ),
    );
  }
}

class MyRootWidget extends StatelessWidget {
  static Widget builder(BuildContext ctx, Widget child) =>
      MyRootWidget(child: child);

  // define order to draw the Drawer menu.
  final drawerOnTop = true;

  const MyRootWidget({Key key, this.child}) : super(key: key);

  final Widget child;

  @override
  Widget build(BuildContext context) {
    final children = <Widget>[
      MyPersistentDrawer(),
      Expanded(child: child),
    ];
    return Scaffold(
      body: Row(
        textDirection: drawerOnTop ? TextDirection.rtl : TextDirection.ltr,
        children: drawerOnTop ? children.reversed.toList() : children,
      ),
    );
  }
}