What are the main tools and libraries for creating and managing animations in projects?

In Flutter, the following main tools and libraries are used for creating and managing animations:

• AnimationController — a base class for controlling animations, setting duration, direction, and state.
• Tween — describes the range of values over which the animation occurs.
• AnimatedBuilder — a widget for building animations using a change listener.
• Implicit Animations (e.g., AnimatedContainer, AnimatedOpacity) — simplified animations that automatically animate changes to their properties.
• flutter_animate — a popular third-party library that simplifies creating complex animations.

Example of a simple opacity animation:

AnimationController controller = AnimationController(
  duration: const Duration(seconds: 2),
  vsync: this,
);
Animation<double> animation = Tween(begin: 0.0, end: 1.0).animate(controller);

AnimatedBuilder(
  animation: animation,
  builder: (context, child) {
    return Opacity(
      opacity: animation.value,
      child: child,
    );
  },
  child: Text('Animation example'),
);

controller.forward();