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Flutter: Vertically center a widget inside a Container

Last updated: April 23, 2023

This article walks you through 4 techniques to vertically center a child widget inside a Container in Flutter.

Using the alignment property

Set the alignment property to Alignment.center, Alignment.centerRight, or Alignment.centerLeft.

Example

 Container(
        width: double.infinity,
        height: 500,
        color: Colors.amber,
        alignment: Alignment.center,
        child: Container(
          width: 200,
          height: 200,
          color: Colors.red,
        ),
),

Output:

Using a Center widget

The Center widget is used to center its child within itself (both vertically and horizontally).

Example:

Container(
        width: double.infinity,
        height: 500,
        color: Colors.amber,
        child: Center(
          child: Container(
            width: 200,
            height: 200,
            color: Colors.purple,
          ),
        ),
      ),

Output:

Adding a Column with mainAxisAlignment

In Flutter, to vertically center a child widget inside a Container, you can wrap the child widget with a Column and add mainAxisAlignment: MainAxisAlignment.center to it.

Example (with full code)

Create a new Flutter project and replace all the default code in ./lib/main.dart file with the following:

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return const MaterialApp(
      // Hide the debug banner
      debugShowCheckedModeBanner: false,

      title: 'Flutter Example',
      home: MyHomePage(),
    );
  }
}

class MyHomePage extends StatelessWidget {
  const MyHomePage({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Scaffold(
        appBar: AppBar(
          title: const Text('Flutter Example'),
        ),
        body: Container(
          height: 600,

          // set the width of this Container to 100% screen width
          width: double.infinity,
          decoration: const BoxDecoration(color: Colors.yellow),

          child: Column(
            // Vertically center the widget inside the column
            mainAxisAlignment: MainAxisAlignment.center,
            children: [
              Container(
                height: 100,
                width: 100,
                decoration: const BoxDecoration(color: Colors.purple),
              ),
            ],
          ),
        ));
  }
}

Output:

Using an Align widget

Wrap the child widget with an Align widget and set the alignment argument to Alignment.center, Alignment.centerLeft, or Alignment.centerRight.

The complete example:

// main.dart
import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return const MaterialApp(
      // Remove the debug banner
      debugShowCheckedModeBanner: false,
      title: 'Kindacode.com',
      home: HomePage(),
    );
  }
}

class HomePage extends StatelessWidget {
  const HomePage({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Kindacode.com'),
      ),
      body: Container(
        color: Colors.green,
        width: double.infinity,
        height: 500,
        child: Align(
          alignment: Alignment.center,
          child: Container(
            width: MediaQuery.of(context).size.width * 0.9,
            height: 100,
            color: Colors.amber,
          ),
        ),
      ),
    );
  }
}

Screenshot:

Wrapping Up

We’ve gone over some different ways for vertically centering a widget inside a Container. Knowing more than one way to solve a problem can help you gain more insight and flexibility in future situations.

Flutter’s awesome, and there’re many things to learn about it. Take a look at the following articles to explore more lovely stuff:

You can also check out our Flutter topic page or Dart topic page for the latest tutorials and examples.