import 'package:flutter/material.dart';

void main() {
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: const MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  const MyHomePage({Key? key, required this.title}) : super(key: key);

  final String title;

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

class _MyHomePageState extends State<MyHomePage> {
 bool selected = false;

  @override
  Widget build(BuildContext context) {
    return SizedBox(
      width: 200,
      height: 350,
      child: Stack(
        children: <Widget>[
          AnimatedPositioned(
            width: selected ? 200.0 : 50.0,
            height: selected ? 50.0 : 200.0,
            top: selected ? 50.0 : 150.0,
            duration: const Duration(seconds: 2),
            curve: Curves.fastOutSlowIn,
            child: GestureDetector(
              onTap: () {
                setState(() {
                  selected = !selected;
                });
              },
              child: Container(
                color: Colors.blue,
                child: const Center(child: Text('Tap me')),
              ),
            ),
          ),
        ],
      ),
    );
  }
}

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