Flutter textformfield error style customization. In this post, I will be discussing and implementing the customization of Flutter textformfield error style. Everything about Flutter textformfield error style will be discussed like what it is, its usage in Flutter textformfield and how can you customize it. So let’s not make you wait anymore and jump directly into the customization Flutter textformfield error style.
What is Flutter Textformfield Error Style?
Flutter textformfield error style, as the name suggests, it is the style of the error text in Flutter textformfield. If you want to have a detailed understanding of what Flutter textformfield error text is then click here. So in this post, we will see how we can change the style of Flutter textformfield.
Default Flutter Textformfield Error Style
To see the default error style, we have to define a simple Flutter textformfield and pass input decoration class in its decoration constructor. Using the error text constructor of the Flutter textformfield, we can see the default Flutter textformfield error style. We have implemented it logically with the condition that when the user enters a blank space the it will show an error. See the below code:
String errorTextvalue = '';
TextFormField( onChanged: (value) { setState(() { if (value.contains(' ')) { errorTextvalue = value; } else { errorTextvalue = ''; } }); }, decoration: InputDecoration( errorText: errorTextvalue.isEmpty ? null : 'Don\'t use blank spaces', ), )

Change Flutter Textformfield Error Style
To change Flutter textformfield error style, we have to use the error style constructor of the input decoration class. The error style constructor text style class which means we can change the error style’s color, font size and many more. For demonstration, I have customized color and font size of error text. See the below code:
errorStyle: TextStyle(color: Colors.green, fontSize: 16))

Custom Flutter Textformfield Design Source Code
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( debugShowCheckedModeBanner: false, home: Homepage(), ); } } class Homepage extends StatefulWidget { @override State<Homepage> createState() => _HomepageState(); } class _HomepageState extends State<Homepage> { String errorTextvalue = ''; @override Widget build(BuildContext context) { return SafeArea( child: Scaffold( body: Center( child: Padding( padding: EdgeInsets.symmetric(horizontal: 40), child: TextFormField( onChanged: (value) { setState(() { if (value.contains(' ')) { errorTextvalue = value; } else { errorTextvalue = ''; } }); }, decoration: InputDecoration( border: InputBorder.none, enabledBorder: OutlineInputBorder( borderRadius: BorderRadius.circular(50), borderSide: BorderSide(color: Colors.purple)), focusedBorder: OutlineInputBorder( borderRadius: BorderRadius.circular(50), borderSide: BorderSide(color: Colors.purple)), errorBorder: OutlineInputBorder( borderRadius: BorderRadius.circular(50), borderSide: BorderSide(color: Colors.red)), focusedErrorBorder: OutlineInputBorder( borderRadius: BorderRadius.circular(50), borderSide: BorderSide(color: Colors.red)), errorText: errorTextvalue.isEmpty ? null : 'Don\'t use blank spaces', errorStyle: TextStyle(color: Colors.green, fontSize: 13)), ))), )); } }
Conclusion
In conclusion, we have learned how to customize Flutter textformfield error style. I look forward to hearing from you regarding this post and invite you to check out my other articles on Flutter app development, Flutter widgets, amazing Flutter templates, Flutter animations, and many more. That’s it for this article. Thank for reading.