Flutter - Animate change on height when child of container renders

Question

I'm trying to recreate something like ExpansionTile but in a Card. When I click the card, its child renders and the card changes its height, so I want to animate that change.

I tried using AnimatedContainer and GlobalKey to know the final size of the card with its child rendered and then set the new height to AnimatedContainer but that didn't work.

Answer 1

In the end I just had to use AnimatedSize. It replicates exactly the animation that I want.

AnimatedSize(
  vsync: this,
  duration: Duration(milliseconds: 150),
  curve: Curves.fastOutSlowIn,
  child: Container(
    child: Container(
      child: !_isExpanded
          ? null
          : FadeTransition(opacity: animationFade, child: widget.child),
    ),
  ),
);