Building Custom Animations and Transitions in Flutter

Animations breathe life into mobile applications, enhancing user engagement and providing intuitive feedback. Flutter’s rich animation libraries empower developers to create captivating visual experiences.

At MetaDesign Solutions, we’ve crafted numerous apps with intricate animations and transitions. In this blog, I’ll guide you through building custom animations in Flutter, sharing techniques and examples from our projects.

Understanding Flutter’s Animation Framework

Flutter offers two primary systems for animations:

Implicit Animations: Simple animations that are easy to implement.
Explicit Animations: Provide more control but require more code.

Implicit Animations with Animated Widgets

Ideal for simple animations involving a change in a widget’s property.

Example: Animating a container’s color change.

dart code

				
					class AnimatedContainerExample extends StatefulWidget {
  @override
  _AnimatedContainerExampleState createState() => _AnimatedContainerExampleState();
}

class _AnimatedContainerExampleState extends State<AnimatedContainerExample> {
  bool selected = false;

  @override
  Widget build(BuildContext context) {
    return GestureDetector(
      onTap: () {
        setState(() {
          selected = !selected;
        });
      },
      child: AnimatedContainer(
        width: selected ? 200.0 : 100.0,
        height: selected ? 100.0 : 200.0,
        color: selected ? Colors.red : Colors.blue,
        alignment: selected ? Alignment.center : AlignmentDirectional.topCenter,
        duration: Duration(seconds: 1),
        curve: Curves.fastOutSlowIn,
        child: Text('Tap me'),
      ),
    );
  }
}

Benefit: Quick and easy to implement without managing animation controllers.

Explicit Animations with Animation Controllers

For more complex animations requiring precise control.

Steps:

Create an AnimationController:
dart code:

				
					AnimationController _controller;

@override
void initState() {
  super.initState();
  _controller = AnimationController(
    duration: const Duration(seconds: 2),
    vsync: this,
  );
}

Define Animation:

dart code:

				
					Animation<double> _animation = Tween<double>(begin: 0, end: 300).animate(_controller);

Use AnimatedBuilder or AnimationWidget:
dart code:

				
					AnimatedBuilder(
  animation: _animation,
  builder: (context, child) {
    return Container(
      width: _animation.value,
      height: _animation.value,
      color: Colors.green,
    );
  },
);

Control the Animation:
dart code:

				
					_controller.forward(); // Start the animation

Note: Remember to dispose of the controller in dispose().

Using the Animation and Tween Classes

Tween: Defines the range of values for the animation.
CurvedAnimation: Applies a curve to the animation for more natural movement.

Example:

dart code:

				
					Animation<double> _animation = Tween<double>(begin: 0, end: 300)
  .animate(CurvedAnimation(
    parent: _controller,
    curve: Curves.easeInOut,
  ));

Hero Animations

Create seamless transitions between screens by animating shared elements.

Implementation:

Wrap the widget in a Hero widget and provide a tag.

dart code:

				
					Hero(
  tag: 'hero-image',
  child: Image.network('https://example.com/image.jpg'),
);

Flutter automatically animates the widget between screens with the same tag.

Custom Transitions with PageRouteBuilder

Define custom transitions when navigating between routes.

Example:

dart code:

				
					Navigator.push(context, PageRouteBuilder(
  pageBuilder: (context, animation, secondaryAnimation) => NextPage(),
  transitionsBuilder: (context, animation, secondaryAnimation, child) {
    return SlideTransition(
      position: Tween<Offset>(
        begin: const Offset(1, 0),
        end: Offset.zero,
      ).animate(animation),
      child: child,
    );
  },
));

Animations in Practice: A Case Study

We developed an e-commerce app that needed to showcase products with engaging animations.

Features Implemented:

Carousel Slider: Animated transitions between featured products.
Add to Cart Animation: Visual feedback when items are added to the cart.
Custom Page Transitions: Smooth navigation between product details and the cart.

Technologies Used:

AnimationController and Tween for precise animations.
Hero widgets for shared element transitions.
Lottie animations for incorporating complex vector animations.

Outcome: Enhanced user engagement and increased time spent in the app.

Tips for Effective Animations

Purposeful Animations: Ensure animations enhance usability, not distract.
Performance Considerations: Keep animations smooth by avoiding heavy computations during animations.
Consistency: Maintain a consistent animation style throughout the app.

Tools and Resources

Lottie for Flutter: Integrate animations created in Adobe After Effects.
Rive: Create and embed interactive animations.
Animation Libraries: Explore packages like flutter_staggered_animations for pre-built effects.

How MetaDesign Solutions Can Help

Our expertise in crafting custom animations can elevate your app’s user experience.

Our Services:

Animation Design: Create engaging animations tailored to your brand.
Implementation: Integrate animations efficiently within your app.
Optimization: Ensure animations run smoothly across devices.

Why Partner With Us:

Creative Team: Designers and developers collaborating to deliver stunning visuals.
Technical Proficiency: Deep understanding of Flutter’s animation frameworks.
User-Centric Approach: Focus on enhancing usability and engagement.

Get in Touch

Interested in adding captivating animations to your Flutter app?

Contact us at sales@metadesignsolutions.com to discuss your ideas.