All 7 Flutter Animations Basics questions
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What is the difference between implicit and explicit animations in Flutter, and which specific approach is generally simpler to actually implement for a straightforward, everyday animation need? How does a Tween work together with an AnimationController to actually define the specific range of values, such as a color or a position, that an animation should smoothly transition between? How does the AnimatedBuilder widget let you efficiently rebuild only the specific part of your widget tree that actually needs to change on every single animation frame, rather than rebuilding an entire larger, unrelated widget subtree unnecessarily? What are animation curves in Flutter, such as Curves.easeIn or Curves.bounceOut, and how do they let you control the specific pacing and feel of an animation rather than it always simply moving at a perfectly constant, linear speed? What performance considerations become important when building a screen containing several simultaneous, continuously running animations, and how can Flutter DevTools help identify a genuine animation related performance problem?
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How can you properly coordinate several separate, related animations together, such as a fade combined with a scale effect, ensuring they all play in perfect sync using a single shared underlying AnimationController?

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Answer

Coordinating multiple related animations together typically means driving each of those separate individual animations, such as one Tween controlling opacity and a completely separate Tween controlling scale, from exactly the same single shared underlying AnimationController, optionally using Intervals to have each specific individual animation only actually become active during a specific particular portion of that overall shared animation's total timeline, letting you build genuinely complex, carefully choreographed multi part animation sequences that all still remain perfectly synchronized together, since they are all fundamentally driven by that exact same single shared underlying progress value.
final fadeAnimation = Tween<double>(begin: 0, end: 1).animate(
  CurvedAnimation(parent: controller, curve: Interval(0.0, 0.5)),
);
final scaleAnimation = Tween<double>(begin: 0.8, end: 1).animate(
  CurvedAnimation(parent: controller, curve: Interval(0.3, 1.0)),
);
Real-world example An onboarding screen's entrance animation coordinates a fade in effect during the first half of the overall animation timeline together with a slightly overlapping scale up effect during the latter portion, both driven by exactly the same single shared AnimationController to guarantee they remain perfectly synchronized together.

Common follow-ups: How do you determine an appropriate overlap between two separate animation intervals for the most visually pleasing combined result?;What happens if two separate animations driven by the exact same controller genuinely need entirely different total durations?

Hero Animations & Page Transitions;Custom Painters & CustomPaint
All 7 Flutter Animations Basics questions