main.dart

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
        home: Scaffold(
      appBar: AppBar(
        title: Text('GridView'),
      ),
      body: LayoutDemo(),
    ));
  }
}

class LayoutDemo extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Container(
      height: 600,
      width: 400,
      color: Colors.pink,
      child: Row(
             mainAxisAlignment: MainAxisAlignment.spaceEvenly,
             crossAxisAlignment: CrossAxisAlignment.start,
             children: <Widget>[
             IconContainer(Icons.search, color: Colors.blue),
             IconContainer(Icons.home, color: Colors.red),
             IconContainer(Icons.bluetooth, color: Colors.orange),
      ],
     ),
    );
  }
}

class IconContainer extends StatelessWidget {
  double size;
  Color color;
  IconData icon;
  IconContainer(this.icon, {this.color, this.size});
  @override
  Widget build(BuildContext context) {
    return Container(
      height: 100.0,
      width: 100.0,
      color: this.color,
      child: Center(
        child: Icon(this.icon, size: this.size, color: Colors.white),
      ),
    );
  }
}