Flutter：如何在 Widget 启动时读取首选项

我一直在try 阅读Widget创业公司的首选项，但一直无法找到解决方案. 我希望在TextField(他们可以更改)中显示用户名，并将其存储在Preferences中，以便在他们返回页面时立即显示.

class _MyHomePageState extends State<MyHomePage> {
  TextEditingController _controller;
  :
  :
  Future<Null> storeName(String name) async {
    SharedPreferences prefs = await SharedPreferences.getInstance();
    prefs.setString("name", name);
  }

  @override
  initState() async {
    super.initState();
    SharedPreferences prefs = await SharedPreferences.getInstance();
    _controller = new TextEditingController(text: prefs.getString("name"));
  }

  @override
  Widget build(BuildContext context) {
  :
  :
  return new TextField(
               decoration: new InputDecoration(
                 hintText: "Name (optional)",
               ),
               onChanged: (String str) {
                 setState(() {
                   _name = str;
                   storeName(str);
                 });
               },
               controller: _controller,
             )
  }
}

I got the idea for using async on initState() from :
flutter timing problems on stateful widget after API call
But the async seems to cause this error on startup :

'package:flutter/src/widgets/framework.dart': Failed assertion: line 967 pos 12: 
'_debugLifecycleState == _StateLifecycle.created': is not true.

我寻找了FutureBuilder的示例，但似乎找不到任何与我正在try 做的事情相似的示例.