How to set width, height, and padding of TextField in Flutter

This article shows you how to set the width, height, and inner padding of a TextField widget in Flutter.

Setting the width of a TextField

You can set the width of a TextField exactly as you want by wrapping it inside a Container, a SizedBox, or a ContrainedBox widget.Advertisements

Note that the height of the parent widget will not affect the height of the text field inside it.

The height of a TextField widget depends on multiple factors and we’ll talk about that in a later section of this tutorial.

Example

Screenshot:

AdvertisementsThe code:

Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Kindacode.com'),
      ),
      body: const Center(
        child: SizedBox(
          width: 250,
          child: TextField(
            decoration: InputDecoration(
              hintText: 'This text field is 250 pixels wide',
            ),
          ),
        ),
      ),
    );
  }

Another example

Screenshot:

The code: Advertisements

// 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: Center(
        child: ConstrainedBox(
          constraints: const BoxConstraints.tightFor(width: 300),
          child: const TextField(
            decoration: InputDecoration(
              hintText: 'This text field is 300 pixels wide',
              border: OutlineInputBorder(),
            ),
          ),
        ),
      ),
    );
  }
}

TextField Inner Padding

You can set the inner padding of a TextField by using the contentPadding property of the InputDecoration class.

Example

Screenshot:

The code:

Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Kindacode.com'),
      ),
      body: const Center(
        child: SizedBox(
          width: 300,
          child: TextField(
            decoration: InputDecoration(
              hintText: 'placeholder text',
              contentPadding:
                  EdgeInsets.symmetric(vertical: 40, horizontal: 20),
              border: OutlineInputBorder(),
            ),
          ),
        ),
      ),
    );
  }

Adjusting the height of a TextField

The height of a TextField depends on its inner padding, font size, and line-height.

The font size can be set by manipulating the fontSize property of the TextStyle class.

The line-height can be adjusted by using the height property of the TextStyle class. When height is non-null, the line-height of the span of text will be a multiple of fontSize and be exactly fontSize * height logical pixels tall.

Words can be long and confusing. The following example will help you understand better.

Example

Screenshot:

The code:

Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Kindacode.com'),
      ),
      body: const Center(
        child: SizedBox(
          width: 300,
          child: TextField(
            style: TextStyle(fontSize: 50, height: 1.5),
            decoration: InputDecoration(
              hintText: 'hint text',
              contentPadding:
                  EdgeInsets.symmetric(vertical: 20, horizontal: 15),
              border: OutlineInputBorder(),
            ),
          ),
        ),
      ),
    );
  }

Final Words

You’ve learned how to adjust the width, height, and inner padding of a TextFeild widget. If you’d like to learn more about Flutter, take a look at the following articles:

• Understanding Typedefs (Type Aliases) in Dart and Flutter
• Flutter and Firestore Database: CRUD example
• 4 Ways to Store Data Offline in Flutter
• Most Popular Packages for State Management in Flutter
• Flutter: Make a TextField Read-Only or Disabled
• Flutter & Hive Database: CRUD Example

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