AnimatedAlign.dart

class MyHomePage extends StatefulWidget {
  const MyHomePage({Key? key}) : super(key: key);

  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  bool animatePosition = false;
  Alignment currentAlignment = Alignment.topLeft;
  late Alignment resultAlignment;
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      bottomNavigationBar: Row(
        children: [
          Expanded(
            child: ElevatedButton(
              onPressed: () {
                setState(() {
                  animatePosition = true;
                  resultAlignment = Alignment.topLeft;
                });
              },
              child: const Text("TopLeft"),
            ),
          ),
          Expanded(
            child: ElevatedButton(
              onPressed: () {
                setState(() {
                  animatePosition = true;
                  resultAlignment = Alignment.topRight;
                });
              },
              child: const Text("TopRight"),
            ),
          ),
          Expanded(
            child: ElevatedButton(
              onPressed: () {
                setState(() {
                  animatePosition = true;
                  resultAlignment = Alignment.topCenter;
                });
              },
              child: const Text("TopCenter"),
            ),
          ),
          // same for other alignment
        ],
      ),
      body: Container(
        color: Colors.blueGrey,
        child: AnimatedAlign(
          alignment: animatePosition ? resultAlignment : currentAlignment,
          duration: const Duration(seconds: 1),
          curve: Curves.fastOutSlowIn,
          child: Container(
            height: 100,
            width: 100,
            color: Colors.green,
          ),
        ),
      ),
    );
  }
}