[Gallery] Fix directory structure (#312)

gallery/lib/studies/starter/app.dart

@@ -0,0 +1,93 @@
+// Copyright 2019 The Flutter team. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter/material.dart';
+import 'package:gallery/data/gallery_options.dart';
+import 'package:gallery/l10n/gallery_localizations.dart';
+import 'package:gallery/layout/focus_traversal_policy.dart';
+import 'package:gallery/pages/home.dart' as home;
+import 'package:gallery/studies/starter/home.dart';
+
+const _primaryColor = Color(0xFF6200EE);
+
+class StarterApp extends StatefulWidget {
+  const StarterApp({Key key, this.navigatorKey}) : super(key: key);
+
+  final GlobalKey<NavigatorState> navigatorKey;
+
+  @override
+  _StarterAppState createState() => _StarterAppState();
+}
+
+class _StarterAppState extends State<StarterApp> {
+  FocusNode firstFocusNode;
+  FocusNode lastFocusNode;
+
+  @override
+  void initState() {
+    super.initState();
+    firstFocusNode = FocusNode();
+    lastFocusNode = FocusNode();
+  }
+
+  @override
+  void dispose() {
+    firstFocusNode.dispose();
+    lastFocusNode.dispose();
+    super.dispose();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final backButtonFocusNode =
+        home.InheritedFocusNodes.of(context).backButtonFocusNode;
+
+    return MaterialApp(
+      navigatorKey: widget.navigatorKey,
+      title: GalleryLocalizations.of(context).starterAppTitle,
+      debugShowCheckedModeBanner: false,
+      localizationsDelegates: GalleryLocalizations.localizationsDelegates,
+      supportedLocales: GalleryLocalizations.supportedLocales,
+      locale: GalleryOptions.of(context).locale,
+      home: DefaultFocusTraversal(
+        policy: EdgeChildrenFocusTraversalPolicy(
+          firstFocusNodeOutsideScope: backButtonFocusNode,
+          lastFocusNodeOutsideScope: backButtonFocusNode,
+          firstFocusNodeInsideScope: firstFocusNode,
+          lastFocusNodeInsideScope: lastFocusNode,
+        ),
+        child: ApplyTextOptions(
+          child: HomePage(
+            firstFocusNode: firstFocusNode,
+            lastFocusNode: lastFocusNode,
+          ),
+        ),
+      ),
+      theme: ThemeData(
+        primaryColor: _primaryColor,
+        highlightColor: Colors.transparent,
+        colorScheme: ColorScheme(
+          primary: _primaryColor,
+          primaryVariant: const Color(0xFF3700B3),
+          secondary: const Color(0xFF03DAC6),
+          secondaryVariant: const Color(0xFF018786),
+          background: Colors.white,
+          surface: Colors.white,
+          onBackground: Colors.black,
+          error: const Color(0xFFB00020),
+          onError: Colors.white,
+          onPrimary: Colors.white,
+          onSecondary: Colors.black,
+          onSurface: Colors.black,
+          brightness: Brightness.light,
+        ),
+        dividerTheme: DividerThemeData(
+          thickness: 1,
+          color: const Color(0xFFE5E5E5),
+        ),
+        platform: GalleryOptions.of(context).platform,
+      ),
+    );
+  }
+}