custom navigation drawer main view code

main.dart

class _MyHomePageState extends State<MyHomePage>
    with SingleTickerProviderStateMixin {
  AnimationController _controller;

  @override
  void initState() {
    super.initState();

    _controller = AnimationController(
        vsync: this, duration: const Duration(milliseconds: 100), value: 1.0);
  }

  @override
  void dispose() {
    super.dispose();
    _controller.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: MainActivity(_controller),
    );
  }