Why You Should Use Custom Widgets Instead of Built-In Widgets in Flutter

Flutter provides an extensive library of built-in widgets, making it easier to build apps quickly. However, relying solely on these widgets might not always be the best approach, especially for apps requiring unique designs, consistent theming, or specific functionality. Building custom widgets can give you more control over your app’s appearance and behavior, leading to a polished and professional product.

Here’s why you should prioritize custom widgets like custom buttons, loaders, and other UI components in your Flutter projects.

1. Consistent Design Across Your App

Custom widgets help maintain a consistent design language throughout your app. For instance, a custom button widget ensures that every button in your app adheres to the same style, size, padding, and behavior, regardless of where it’s used.

Example: Customizing a button once and reusing it throughout your app.

class CustomButton extends StatelessWidget {
  final String title;
  final VoidCallback onPressed;

  const CustomButton({
    Key? key,
    required this.title,
    required this.onPressed,
  }) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return ElevatedButton(
      onPressed: onPressed,
      child: Text(title),
      style: ElevatedButton.styleFrom(
        padding: EdgeInsets.symmetric(vertical: 12, horizontal: 20),
        textStyle: TextStyle(fontSize: 16, fontWeight: FontWeight.bold),
      ),
    );
  }
}        

By using this custom button widget, you ensure all buttons in your app follow the same design, reducing inconsistencies.

2. Enhanced Code Reusability

Custom widgets encapsulate design and logic, allowing you to reuse them across multiple screens or projects. Instead of writing repetitive styling code for each built-in widget, custom widgets centralize these properties, saving time and effort.

3. Better Maintainability

With custom widgets, making global design updates becomes easier. For example, changing the color of all loaders in your app only requires an update in your custom loader widget, instead of manually updating each instance of a built-in loader.

Example: Custom loader widget.

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

  @override
  Widget build(BuildContext context) {
    return Center(
      child: CircularProgressIndicator(
        valueColor: AlwaysStoppedAnimation<Color>(Colors.blue),
        strokeWidth: 4.0,
      ),
    );
  }
}        

4. Branding and Unique UI

For apps that aim to stand out, custom widgets allow you to implement branding-specific UI elements. Built-in widgets are generic and may not align with your app's theme or branding requirements.

For example, a custom button can incorporate brand colors, logos, or animations that built-in widgets can’t achieve directly.

5. Optimized Performance for Specific Use Cases

Custom widgets can be tailored to meet your app’s unique performance requirements. For example, instead of using a built-in list widget that loads all items, you can create a custom lazy-loading list that optimizes resource usage.

6. Simplified Theming and Scalability

Custom widgets make it easier to implement and scale themes. By using a custom text field or button widget, you can ensure that your app adheres to dark and light themes with minimal effort.

Example: Custom text field for consistent input styling.

class CustomTextField extends StatelessWidget {
  final String hintText;
  final TextEditingController controller;

  const CustomTextField({
    Key? key,
    required this.hintText,
    required this.controller,
  }) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return TextField(
      controller: controller,
      decoration: InputDecoration(
        hintText: hintText,
        border: OutlineInputBorder(borderRadius: BorderRadius.circular(8)),
        contentPadding: EdgeInsets.symmetric(vertical: 10, horizontal: 15),
      ),
    );
  }
}        

7. Reduced Development Time for Future Projects

Once you’ve created a library of custom widgets, you can reuse them across multiple projects, drastically reducing development time. A reusable library of custom widgets acts as a foundation, helping you build apps faster without compromising on quality.