Implementing Flutter Animations

Contents

• Core Concepts
• Animation Strategies
• Workflows
  • Implementing Implicit Animations
  • Implementing Explicit Animations
  • Implementing Hero Transitions
  • Implementing Physics-Based Animations
• Examples

Core Concepts

Manage Flutter animations using the core typed Animation system. Do not manually calculate frames; rely on the framework's ticker and interpolation classes.

• Animation<T>: Treat this as an abstract representation of a value that changes over time. It holds state (completed, dismissed) and notifies listeners, but knows nothing about the UI.
• AnimationController: Instantiate this to drive the animation. It generates values (typically 0.0 to 1.0) tied to the screen refresh rate. Always provide a vsync (usually via SingleTickerProviderStateMixin) to prevent offscreen resource consumption. Always dispose() controllers to prevent memory leaks.
• Tween<T>: Define a stateless mapping from an input range (usually 0.0-1.0) to an output type (e.g., Color, Offset, double). Chain tweens with curves using .animate().
• Curve: Apply non-linear timing (e.g., Curves.easeIn, Curves.bounceOut) to an animation using a CurvedAnimation or CurveTween.

Animation Strategies

Apply conditional logic to select the correct animation approach: