How can I make my textfield fill the available vertical space?

Issue

I have the following widget

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 MaterialApp(
      title: 'Playground',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: const MyHomePage(),
    );
  }
}

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

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: Colors.green,
      body: Align(
        alignment: Alignment.bottomCenter,
        child: Container(
          height: 100,
          color: Colors.black,
          child: const ResponsiveInput(),
        ),
      ),
    );
  }
}

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

  @override
  Widget build(BuildContext context) {
    return Row(
      crossAxisAlignment: CrossAxisAlignment.stretch,
      children: [
        Expanded(
          child: TextFormField(
            decoration: const InputDecoration(
              fillColor: Colors.white,
              filled: true,
            ),
          ),
        ),
        TextButton(
          onPressed: () => false,
          child: const Text('Send'),
          style: ButtonStyle(
              backgroundColor: MaterialStateProperty.all(Colors.orange)),
        )
      ],
    );
  }
}

Which does the following

[![enter image description here][1]][1]

But how do I make the textfield fill the remaining space in the black container?

I tried using content padding, but what happens is that if the container has responsive height the text will be cut off. Even when using dense.

Solution

You can use expands: true, maxLines: null, on TextFormField

expands If set to true and wrapped in a parent widget like Expanded or SizedBox, the input will expand to fill the parent.

Expanded(
  child: TextFormField(
    expands: true,
    maxLines: null,
    decoration: const InputDecoration(
      fillColor: Colors.white,
      filled: true,
    ),
  ),
),

More about expands

Answered By – Yeasin Sheikh

Answer Checked By – Robin (FlutterFixes Admin)