If you're a Flutter developer keeping up with the latest releases, you've probably noticed that Flutter 3.38 introduced some elegant syntax improvements that can significantly clean up your code. Today, I want to share one particular update that caught my attention: the new constructor syntax for initializing objects like TextEditingController.
What's New in Flutter 3.38?
Flutter 3.38 brings a more concise way to initialize objects when you've already declared their type explicitly. This isn't just about saving a few characters—it's about writing more maintainable, readable code that follows modern Dart conventions.
Let me show you exactly what changed and why it matters for your Flutter projects.
Flutter TextEditingController: Old vs New Syntax
The Traditional Way (Pre-Flutter 3.38)
Before Flutter 3.38, we had two standard approaches to creating a TextEditingController:
Method 1 Using var
var nameController = TextEditingController();Method 2 Explicit Type
TextEditingController nameController1 =
TextEditingController(text: "Codemicros");This worked perfectly fine, and you'll still see this pattern in countless Flutter tutorials and existing codebases.
The Modern Way (Flutter 3.38+)
With Flutter 3.38, you can now use the streamlined .new() constructor syntax:
Flutter 3.38+ New Syntax
TextEditingController nameController2 = .new(text: "Codemicros");Notice how we no longer need to repeat the class name on the right side when we've already declared it on the left. This is what I call "smart redundancy reduction."
Why Flutter 3.38's Constructor Syntax Matters
As someone who's been working with Flutter since the early days, I appreciate updates that make code more maintainable. Here's why this change is more significant than it might appear:
1. Eliminates Redundancy
When you write TextEditingController nameController = TextEditingController(), you're essentially saying the same thing twice. Flutter 3.38 recognizes this and lets you skip the repetition.
2. Scales Better with Complex Types
The benefit becomes even more apparent with longer class names or generic types:
// Before Flutter 3.38
AnimationController animController = AnimationController(
duration: Duration(seconds: 2),
vsync: this,
);
// After Flutter 3.38
AnimationController animController = .new(
duration: Duration(seconds: 2),
vsync: this,
);3. Aligns with Modern Dart Best Practices
This syntax follows Dart 3's direction of reducing boilerplate while maintaining type safety. It's part of a broader effort to make Flutter development more enjoyable.
Real-World Flutter 3.38 Example: Form Controllers
Here's a practical example from a recent project I worked on, showing how the new syntax looks in a typical Flutter form:
class LoginScreen extends StatefulWidget {
const LoginScreen({Key? key}) : super(key: key);
@override
State<LoginScreen> createState() => _LoginScreenState();
}
class _LoginScreenState extends State<LoginScreen> {
// Flutter 3.38 new constructor syntax
TextEditingController emailController = .new();
TextEditingController passwordController = .new();
TextEditingController nameController = .new(text: "John Doe");
final _formKey = GlobalKey<FormState>();
@override
void dispose() {
// Always dispose controllers to prevent memory leaks
emailController.dispose();
passwordController.dispose();
nameController.dispose();
super.dispose();
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(title: const Text('Login')),
body: Padding(
padding: const EdgeInsets.all(16.0),
child: Form(
key: _formKey,
child: Column(
children: [
TextFormField(
controller: nameController,
decoration: const InputDecoration(labelText: 'Name'),
),
const SizedBox(height: 16),
TextFormField(
controller: emailController,
decoration: const InputDecoration(labelText: 'Email'),
keyboardType: TextInputType.emailAddress,
),
const SizedBox(height: 16),
TextFormField(
controller: passwordController,
decoration: const InputDecoration(labelText: 'Password'),
obscureText: true,
),
],
),
),
),
);
}
}The code is cleaner, easier to scan, and the intent is immediately clear.
When Should You Use Flutter 3.38's New Syntax?
Based on my experience migrating several projects to Flutter 3.38, here's my recommendation:
Use the new .new() syntax when:
- You've explicitly declared the type (as shown above)
- You want to reduce visual clutter in controller-heavy widgets
- You're starting a new Flutter 3.38+ project
Stick with the traditional syntax when:
- Using
varorfinalwith type inference (the compiler needs the class name) - Working on a team that hasn't upgraded to Flutter 3.38 yet
- Maintaining legacy code where consistency matters more than modernization
Migration Guide: Updating to Flutter 3.38 Syntax
You don't need to rush and update all your existing code. Both syntaxes work identically at runtime. However, for new code in Flutter 3.38+ projects, I recommend adopting the new pattern.
Here's a quick before-and-after checklist:
Before Pre-3.38
TextEditingController controller =
TextEditingController(text: "Hello");
ScrollController scrollController =
ScrollController();
AnimationController animController =
AnimationController(vsync: this);After Flutter 3.38+
TextEditingController controller =
.new(text: "Hello");
ScrollController scrollController =
.new();
AnimationController animController =
.new(vsync: this);Flutter 3.38 Performance Considerations
One question I've been asked frequently: does the new syntax affect performance?
The short answer is no. This is purely a syntactic feature that exists at compile-time. The generated bytecode is identical whether you use .new() or the full constructor name. It's a developer experience improvement, not a runtime optimization.
Best Practices for Flutter 3.38 Projects
After working with Flutter 3.38 on several production apps, here are my recommendations:
- Be Consistent: Choose one style for your project and stick with it. Document your choice in your team's style guide.
- Update Gradually: Don't rush to refactor existing code. Focus on using the new syntax in new files and during natural refactoring cycles.
- Communicate with Your Team: Make sure everyone understands the new syntax before adopting it widely.
- Check Your Flutter Version: Verify you're running Flutter 3.38 or higher with
flutter --version.
Updating to Flutter 3.38
If you haven't upgraded yet, it's straightforward:
flutter upgrade
flutter --version # Should show 3.38.0 or higherThen update your pubspec.yaml:
environment:
sdk: '>=3.0.0 <4.0.0'
flutter: '>=3.38.0'Final Thoughts on Flutter 3.38's Constructor Syntax
Flutter 3.38's new constructor syntax is a small but meaningful improvement that demonstrates the framework's maturity. While it might seem like syntactic sugar, these incremental enhancements compound to make Flutter development more pleasant and productive.
I've been using this syntax in production for the past few weeks, and it's become second nature. The reduced visual noise in files with many controllers is noticeable, and code reviews have become slightly faster.
Whether you adopt it immediately or stick with the traditional approach, the important thing is that Flutter continues to evolve based on real developer feedback. That's the kind of framework evolution I can get behind.
🎯 Key Takeaways
- Flutter 3.38 introduced
.new()constructor syntax for cleaner object initialization - Works with TextEditingController, ScrollController, AnimationController, and other Flutter classes
- No performance impact—purely a developer experience improvement
- Both old and new syntax remain valid
- Upgrade to Flutter 3.38+ to start using this feature
Have you upgraded to Flutter 3.38 yet? How are you finding the new constructor syntax? Drop your thoughts in the comments below—I'd love to hear about your experience!
