@override
  Widget build(BuildContext context) {
    return new Scaffold(
      appBar: new AppBar(
        title: new Text(widget.title),
      ),
      body: new DropdownButton<int>(
        items: new List<DropdownMenuItem<int>>.generate(
          50,
          (int index) => new DropdownMenuItem<int>(
                value: index,
                child: new Text(index.toString()),
              ),
        ),
        onChanged: (int value) {},
      ),
    );
  }

Doctor summary (to see all details, run flutter doctor -v):
[√] Flutter (Channel beta, v0.1.5, on Microsoft Windows [version 10.0.16299.248], locale fr-FR)
[√] Android toolchain - develop for Android devices (Android SDK 27.0.3)
[√] Android Studio (version 3.0)
[√] IntelliJ IDEA Ultimate Edition (version 2017.3)
[√] VS Code (version 1.20.1)
[√] Connected devices (1 available)

• No issues found!