如何在Flutter中将国际化对象传递给子窗口小部件

刚刚开始使用Flutter / dart，转换为PHP，并努力弄清楚如何将类传递给小部件 .

我正在使用flutter创建我的第一个android和iOS应用程序 .

我正在使用国际化，一切正常，在我的初始构建页面上使用我的国际化课程 . 但是，当它传递给另一个小部件时，我得到：

NoSuchMethodError：在null上调用getter textTitle . Receiver：null尝试调用：textTitle

处理这个问题的最佳方法是什么？

Flutter Doctor

[✓] Flutter (Channel beta, v0.1.5, on Mac OS X 10.13.3 17D47, locale en-US)
  [✓] Android toolchain - develop for Android devices (Android SDK 27.0.1)
  [✓] Android Studio (version 3.0)
  [✓] Connected devices (1 available)

Localization dart

class HnLocalizations{
        HnLocalizations(this.locale);

        final Locale locale;

        static HnLocalizations of(BuildContext context){
            return Localizations.of<HnLocalizations>(context, HnLocalizations);
        }

        static Map<String, Map<String, String>> _localizedValues = {
            'en': {
                'btnLabelLoginS1': 'Login',
                'btnLabelRegisterS1': 'Sign Up'
            },
        ;

        String get s1ButtonLabelLogin =>
            _localizedValues[locale.languageCode]['btnLabelLoginS1'];

class HnLocalizationsDelegate extends LocalizationsDelegate<HnLocalizations> {
        const HnLocalizationsDelegate();

        @override
        bool isSupported(Locale locale) => ['en', 'es'].contains(locale.languageCode);

        @override
        Future<HnLocalizations> load(Locale locale) =>
            new SynchronousFuture<HnLocalizations>(new HnLocalizations(locale)); //HnLocalizations.load(locale);

        @override
        bool shouldReload(HnLocalizationsDelegate old) => false;
    }

Main Dart

void main() {

        runApp(new MaterialApp(
            localizationsDelegates: [
                const HnLocalizationsDelegate(),
                GlobalMaterialLocalizations.delegate,
                GlobalWidgetsLocalizations.delegate,
            ],
            supportedLocales: [
                const Locale('en', 'US'), /// Americans
                const Locale('en', 'GB') /// Brits
            ],
            title: 'HN',
            home: new EntryPage(),
        ));

    }

    class EntryPage extends StatelessWidget {

       final HnColors _hnColors = new HnColors();

        @override
        Widget build(BuildContext context) {

            return new Scaffold(
                appBar: new AppBar(
                    // !!!**** THIS WORKS AS EXPECTED ****!!!!
                    title: new Text(HnLocalizations.of(context).s1ButtonLabelLogin),
                    backgroundColor: _hnColors.transparent(),
                    elevation: 0.0,
                ),
                backgroundColor: _hnColors.accent(),
                body: new Container(
                    decoration: new BoxDecoration(
                        image: new DecorationImage(
                            image: new AssetImage("assets/Background_World.png"),
                            fit: BoxFit.fitWidth,
                        ),
                    ),
                    child: new PanelArea(),
                )
            );
        }
    }


    class PanelArea extends StatelessWidget {

        @override
        Widget build(BuildContext context) {

            HnColors _hnColors = new HnColors();

            return new Container(
                child: new Center(
                    child: new Container(
                        decoration: new BoxDecoration(
                            borderRadius: new BorderRadius.circular(15.0),
                            color: _hnColors.transparent()
                        ),
                        child: new Column(
                            children: [
                                new Image.asset('assets/Icon_Intro_login'),
                                new Text(
                                    // !!!**** ERROR IS HERE ****!!!!
                                    HnLocalizations.of(context).s1M1HeaderTitle,
                                    style: new TextStyle(
                                        color: _haillioColors.white()
                                    ),
                                ),

处理这个问题的最佳方法是什么？

Update: Mar 11 2018
我发现如果我将所有代码移动到main.dart文件中 . 所有本地化都很好 . 但是，当我将我的小部件移动到单独的dart文件中时，即使所有代码都相同，错误也会返回 .

Update: Mar 12 2018 nicolás-carrasco由a reference in this post指出正确的方向（谢谢） . 这个问题与进口问题有关in this post here这最终成为了对我有用的解决方案 . 下面在答案中添加了该示例 .