@override
 Widget build(BuildContext context) {
return new Scaffold(
  appBar: new AppBar(
    title: new Text("App bar"),
  ),
  body: new FutureBuilder<FirebaseUser>(
    future: FirebaseAuth.instance.currentUser(),
    builder: (BuildContext context, AsyncSnapshot<FirebaseUser> snapshot) {
      if (snapshot.connectionState == ConnectionState.done) {
        print(snapshot.data);
        return new Text("hi");
      }
      else {
        return new Text('Loading...');
      }
    },
  ),
);
}