AnimatedWidgetStack class

Draws widgets stack. Can use any widgets. Calls widgetChangeBuilder builder to create animated widget and show a transition between old and current stackedWidgets. Each widget of stackedWidgets should contain an unique key.

Example:

class Example extends StatefulWidget {
  const Example({super.key});

  @override
  State<AnimatedExample1Default> createState() => _AnimatedExample1DefaultState();
}

class _AnimatedExample1DefaultState extends State<AnimatedExample1Default> {
  late List<Widget> _stackedWidgets =
      List.generate(5, (index) => index).map((index) => _generateAvatar(index)).toList();

  Widget _generateAvatar(int index) => BorderedCircleAvatar(
        key: _generateKey(index),
        border: const BorderSide(color: Colors.orange, width: 2.0),
        backgroundImage: NetworkImage(getAvatarUrl(index)),
        constraints: const BoxConstraints.expand(),
      );

  Key _generateKey(int index) => Key('BCA_$index');

  Widget _infoItemBuilder(int surplus, BuildContext context) => BorderedCircleAvatar(
        constraints: const BoxConstraints.expand(),
        child: Center(child: Text('+$surplus')),
      );

  @override
  Widget build(BuildContext context) {
    return SizedBox(
      height: 50,
      child: AnimatedWidgetStack(
        positions: RestrictedPositions(maxCoverage: 0.5, minCoverage: 0.3),
        stackedWidgets: _stackedWidgets,
        widgetChangeBuilder: (context, action, constraints) {
          return WidgetWithParameters(
            widget: DefaultAnimatedAction(
              key: action.key,
              action: action,
              size: constraints.biggest,
              infoWidgetBuilder: _infoItemBuilder,
            ),
          );
        },
      ),
    );
  }
}