[Gallery] Fix directory structure (#312)

gallery/lib/demos/material/button_demo.dart

@@ -0,0 +1,214 @@
+// 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/l10n/gallery_localizations.dart';
+
+enum ButtonDemoType {
+  flat,
+  raised,
+  outline,
+  toggle,
+  floating,
+}
+
+class ButtonDemo extends StatelessWidget {
+  const ButtonDemo({Key key, this.type}) : super(key: key);
+
+  final ButtonDemoType type;
+
+  String _title(BuildContext context) {
+    switch (type) {
+      case ButtonDemoType.flat:
+        return GalleryLocalizations.of(context).demoFlatButtonTitle;
+      case ButtonDemoType.raised:
+        return GalleryLocalizations.of(context).demoRaisedButtonTitle;
+      case ButtonDemoType.outline:
+        return GalleryLocalizations.of(context).demoOutlineButtonTitle;
+      case ButtonDemoType.toggle:
+        return GalleryLocalizations.of(context).demoToggleButtonTitle;
+      case ButtonDemoType.floating:
+        return GalleryLocalizations.of(context).demoFloatingButtonTitle;
+    }
+    return '';
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    Widget buttons;
+    switch (type) {
+      case ButtonDemoType.flat:
+        buttons = _FlatButtonDemo();
+        break;
+      case ButtonDemoType.raised:
+        buttons = _RaisedButtonDemo();
+        break;
+      case ButtonDemoType.outline:
+        buttons = _OutlineButtonDemo();
+        break;
+      case ButtonDemoType.toggle:
+        buttons = _ToggleButtonsDemo();
+        break;
+      case ButtonDemoType.floating:
+        buttons = _FloatingActionButtonDemo();
+        break;
+    }
+
+    return Scaffold(
+      appBar: AppBar(
+        automaticallyImplyLeading: false,
+        title: Text(_title(context)),
+      ),
+      body: buttons,
+    );
+  }
+}
+
+// BEGIN buttonDemoFlat
+
+class _FlatButtonDemo extends StatelessWidget {
+  @override
+  Widget build(BuildContext context) {
+    return Center(
+      child: Column(
+        mainAxisSize: MainAxisSize.min,
+        children: [
+          FlatButton(
+            child: Text(GalleryLocalizations.of(context).buttonText),
+            onPressed: () {},
+          ),
+          SizedBox(height: 12),
+          FlatButton.icon(
+            icon: const Icon(Icons.add, size: 18),
+            label: Text(GalleryLocalizations.of(context).buttonText),
+            onPressed: () {},
+          ),
+        ],
+      ),
+    );
+  }
+}
+
+// END
+
+// BEGIN buttonDemoRaised
+
+class _RaisedButtonDemo extends StatelessWidget {
+  @override
+  Widget build(BuildContext context) {
+    return Center(
+      child: Column(
+        mainAxisSize: MainAxisSize.min,
+        children: [
+          RaisedButton(
+            child: Text(GalleryLocalizations.of(context).buttonText),
+            onPressed: () {},
+          ),
+          SizedBox(height: 12),
+          RaisedButton.icon(
+            icon: const Icon(Icons.add, size: 18),
+            label: Text(GalleryLocalizations.of(context).buttonText),
+            onPressed: () {},
+          ),
+        ],
+      ),
+    );
+  }
+}
+
+// END
+
+// BEGIN buttonDemoOutline
+
+class _OutlineButtonDemo extends StatelessWidget {
+  @override
+  Widget build(BuildContext context) {
+    return Center(
+      child: Column(
+        mainAxisSize: MainAxisSize.min,
+        children: [
+          OutlineButton(
+            // TODO: Should update to OutlineButton follow material spec.
+            highlightedBorderColor:
+                Theme.of(context).colorScheme.onSurface.withOpacity(0.12),
+            child: Text(GalleryLocalizations.of(context).buttonText),
+            onPressed: () {},
+          ),
+          SizedBox(height: 12),
+          OutlineButton.icon(
+            // TODO: Should update to OutlineButton follow material spec.
+            highlightedBorderColor:
+                Theme.of(context).colorScheme.onSurface.withOpacity(0.12),
+            icon: const Icon(Icons.add, size: 18),
+            label: Text(GalleryLocalizations.of(context).buttonText),
+            onPressed: () {},
+          ),
+        ],
+      ),
+    );
+  }
+}
+
+// END
+
+// BEGIN buttonDemoToggle
+
+class _ToggleButtonsDemo extends StatefulWidget {
+  @override
+  _ToggleButtonsDemoState createState() => _ToggleButtonsDemoState();
+}
+
+class _ToggleButtonsDemoState extends State<_ToggleButtonsDemo> {
+  final isSelected = <bool>[false, false, false];
+
+  @override
+  Widget build(BuildContext context) {
+    return Center(
+      child: ToggleButtons(
+        children: [
+          Icon(Icons.ac_unit),
+          Icon(Icons.call),
+          Icon(Icons.cake),
+        ],
+        onPressed: (index) {
+          setState(() {
+            isSelected[index] = !isSelected[index];
+          });
+        },
+        isSelected: isSelected,
+      ),
+    );
+  }
+}
+
+// END
+
+// BEGIN buttonDemoFloating
+
+class _FloatingActionButtonDemo extends StatelessWidget {
+  @override
+  Widget build(BuildContext context) {
+    return Center(
+      child: Column(
+        mainAxisSize: MainAxisSize.min,
+        children: [
+          FloatingActionButton(
+            child: const Icon(Icons.add),
+            onPressed: () {},
+            tooltip: GalleryLocalizations.of(context).buttonTextCreate,
+          ),
+          SizedBox(height: 20),
+          FloatingActionButton.extended(
+            icon: const Icon(Icons.add),
+            label: Text(GalleryLocalizations.of(context).buttonTextCreate),
+            onPressed: () {},
+          ),
+        ],
+      ),
+    );
+  }
+}
+
+// END