column_posistion.dart

import 'package:flutter/material.dart';

const Color darkBlue = Color.fromARGB(255, 18, 32, 47);

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      theme: ThemeData.dark().copyWith(
        scaffoldBackgroundColor: darkBlue,
      ),
      debugShowCheckedModeBanner: false,
      home: Scaffold(
        body: Center(
          child: ColumnPositioned(),
        ),
      ),
    );
  }
}


class ColumnPositioned extends StatefulWidget {
  @override
  _ColumnPositionedState createState() => _ColumnPositionedState();
}

class _ColumnPositionedState extends State<ColumnPositioned>{

  @override
  void initState() {
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Row(
        mainAxisAlignment: MainAxisAlignment.spaceAround,
        crossAxisAlignment: CrossAxisAlignment.center,
        children: [
          Expanded(child: Container(
            color: Colors.yellow,
            height: 50,
          ),),
          Expanded(
            child: Row(
              mainAxisAlignment: MainAxisAlignment.start,
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                Expanded(child: Container(
                  color: Colors.brown,
                  height: 50,
                ),),
                Expanded(
                  child: Column( children: [
                    Column(
                      children: [
                        Container(
                          color: Colors.green,
                          height: 50,
                        ),
                        Container(
                          color: Colors.blue,
                          height: 50,
                        ),
                      ], // top widgets
                    ),
                    Spacer(),
                    Container(
                      color: Colors.yellow,
                      height: 50,
                    ) // bottom widget
                  ]),
                )
              ],
            ),
          )
        ],
      ),
    );
  }
}