[Gallery] Refactor list of demos to use common variables (#224)

gallery/gallery/lib/data/demos.dart

@@ -38,6 +38,8 @@ import 'package:gallery/demos/reference/typography_demo.dart';
 import 'package:gallery/l10n/gallery_localizations.dart';
 import 'package:gallery/themes/material_demo_theme_data.dart';
 
+const _docsBaseUrl = 'https://api.flutter.dev/flutter';
+
 class GalleryDemo {
   GalleryDemo({
     @required this.title,
@@ -71,46 +73,41 @@ class GalleryDemoConfiguration {
 }
 
 List<GalleryDemo> materialDemos(BuildContext context) {
+  final localizations = GalleryLocalizations.of(context);
   return [
     GalleryDemo(
-      title: GalleryLocalizations.of(context).demoBottomAppBarTitle,
+      title: localizations.demoBottomAppBarTitle,
       icon: GalleryIcons.bottomAppBar,
-      subtitle: GalleryLocalizations.of(context).demoBottomAppBarSubtitle,
+      subtitle: localizations.demoBottomAppBarSubtitle,
       configurations: [
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoBottomAppBarTitle,
-          description:
-              GalleryLocalizations.of(context).demoBottomAppBarDescription,
-          documentationUrl:
-              'https://api.flutter.dev/flutter/material/BottomAppBar-class.html',
+          title: localizations.demoBottomAppBarTitle,
+          description: localizations.demoBottomAppBarDescription,
+          documentationUrl: '$_docsBaseUrl/material/BottomAppBar-class.html',
           buildRoute: (_) => BottomAppBarDemo(),
           code: CodeSegments.bottomAppBarDemo,
         ),
       ],
     ),
     GalleryDemo(
-      title: GalleryLocalizations.of(context).demoBottomNavigationTitle,
+      title: localizations.demoBottomNavigationTitle,
       icon: GalleryIcons.bottomNavigation,
-      subtitle: GalleryLocalizations.of(context).demoBottomNavigationSubtitle,
+      subtitle: localizations.demoBottomNavigationSubtitle,
       configurations: [
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context)
-              .demoBottomNavigationPersistentLabels,
-          description:
-              GalleryLocalizations.of(context).demoBottomNavigationDescription,
+          title: localizations.demoBottomNavigationPersistentLabels,
+          description: localizations.demoBottomNavigationDescription,
           documentationUrl:
-              'https://api.flutter.dev/flutter/material/BottomNavigationBar-class.html',
+              '$_docsBaseUrl/material/BottomNavigationBar-class.html',
           buildRoute: (_) =>
               BottomNavigationDemo(type: BottomNavigationDemoType.withLabels),
           code: CodeSegments.bottomNavigationDemo,
         ),
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context)
-              .demoBottomNavigationSelectedLabel,
-          description:
-              GalleryLocalizations.of(context).demoBottomNavigationDescription,
+          title: localizations.demoBottomNavigationSelectedLabel,
+          description: localizations.demoBottomNavigationDescription,
           documentationUrl:
-              'https://api.flutter.dev/flutter/material/BottomNavigationBar-class.html',
+              '$_docsBaseUrl/material/BottomNavigationBar-class.html',
           buildRoute: (_) => BottomNavigationDemo(
               type: BottomNavigationDemoType.withoutLabels),
           code: CodeSegments.bottomNavigationDemo,
@@ -118,77 +115,67 @@ List<GalleryDemo> materialDemos(BuildContext context) {
       ],
     ),
     GalleryDemo(
-      title: GalleryLocalizations.of(context).demoBottomSheetTitle,
+      title: localizations.demoBottomSheetTitle,
       icon: GalleryIcons.bottomSheets,
-      subtitle: GalleryLocalizations.of(context).demoBottomSheetSubtitle,
+      subtitle: localizations.demoBottomSheetSubtitle,
       configurations: [
         GalleryDemoConfiguration(
-          title:
-              GalleryLocalizations.of(context).demoBottomSheetPersistentTitle,
-          description: GalleryLocalizations.of(context)
-              .demoBottomSheetPersistentDescription,
-          documentationUrl:
-              'https://api.flutter.dev/flutter/material/BottomSheet-class.html',
+          title: localizations.demoBottomSheetPersistentTitle,
+          description: localizations.demoBottomSheetPersistentDescription,
+          documentationUrl: '$_docsBaseUrl/material/BottomSheet-class.html',
           buildRoute: (_) =>
               BottomSheetDemo(type: BottomSheetDemoType.persistent),
           code: CodeSegments.bottomSheetDemoPersistent,
         ),
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoBottomSheetModalTitle,
-          description:
-              GalleryLocalizations.of(context).demoBottomSheetModalDescription,
-          documentationUrl:
-              'https://api.flutter.dev/flutter/material/BottomSheet-class.html',
+          title: localizations.demoBottomSheetModalTitle,
+          description: localizations.demoBottomSheetModalDescription,
+          documentationUrl: '$_docsBaseUrl/material/BottomSheet-class.html',
           buildRoute: (_) => BottomSheetDemo(type: BottomSheetDemoType.modal),
           code: CodeSegments.bottomSheetDemoModal,
         ),
       ],
     ),
     GalleryDemo(
-      title: GalleryLocalizations.of(context).demoButtonTitle,
+      title: localizations.demoButtonTitle,
       icon: GalleryIcons.genericButtons,
-      subtitle: GalleryLocalizations.of(context).demoButtonSubtitle,
+      subtitle: localizations.demoButtonSubtitle,
       configurations: [
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoFlatButtonTitle,
-          description:
-              GalleryLocalizations.of(context).demoFlatButtonDescription,
+          title: localizations.demoFlatButtonTitle,
+          description: localizations.demoFlatButtonDescription,
           documentationUrl:
               'https://docs.flutter.io/flutter/material/FlatButton-class.html',
           buildRoute: (_) => ButtonDemo(type: ButtonDemoType.flat),
           code: CodeSegments.buttonDemoFlat,
         ),
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoRaisedButtonTitle,
-          description:
-              GalleryLocalizations.of(context).demoRaisedButtonDescription,
+          title: localizations.demoRaisedButtonTitle,
+          description: localizations.demoRaisedButtonDescription,
           documentationUrl:
               'https://docs.flutter.io/flutter/material/RaisedButton-class.html',
           buildRoute: (_) => ButtonDemo(type: ButtonDemoType.raised),
           code: CodeSegments.buttonDemoRaised,
         ),
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoOutlineButtonTitle,
-          description:
-              GalleryLocalizations.of(context).demoOutlineButtonDescription,
+          title: localizations.demoOutlineButtonTitle,
+          description: localizations.demoOutlineButtonDescription,
           documentationUrl:
               'https://docs.flutter.io/flutter/material/OutlineButton-class.html',
           buildRoute: (_) => ButtonDemo(type: ButtonDemoType.outline),
           code: CodeSegments.buttonDemoOutline,
         ),
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoToggleButtonTitle,
-          description:
-              GalleryLocalizations.of(context).demoToggleButtonDescription,
+          title: localizations.demoToggleButtonTitle,
+          description: localizations.demoToggleButtonDescription,
           documentationUrl:
               'https://docs.flutter.io/flutter/material/ToggleButtons-class.html',
           buildRoute: (_) => ButtonDemo(type: ButtonDemoType.toggle),
           code: CodeSegments.buttonDemoToggle,
         ),
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoFloatingButtonTitle,
-          description:
-              GalleryLocalizations.of(context).demoFloatingButtonDescription,
+          title: localizations.demoFloatingButtonTitle,
+          description: localizations.demoFloatingButtonDescription,
           documentationUrl:
               'https://docs.flutter.io/flutter/material/FloatingActionButton-class.html',
           buildRoute: (_) => ButtonDemo(type: ButtonDemoType.floating),
@@ -197,189 +184,163 @@ List<GalleryDemo> materialDemos(BuildContext context) {
       ],
     ),
     GalleryDemo(
-      title: GalleryLocalizations.of(context).demoChipTitle,
+      title: localizations.demoChipTitle,
       icon: GalleryIcons.chips,
-      subtitle: GalleryLocalizations.of(context).demoChipSubtitle,
+      subtitle: localizations.demoChipSubtitle,
       configurations: [
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoActionChipTitle,
-          description:
-              GalleryLocalizations.of(context).demoActionChipDescription,
-          documentationUrl:
-              'https://api.flutter.dev/flutter/material/ActionChip-class.html',
+          title: localizations.demoActionChipTitle,
+          description: localizations.demoActionChipDescription,
+          documentationUrl: '$_docsBaseUrl/material/ActionChip-class.html',
           buildRoute: (_) => ChipDemo(type: ChipDemoType.action),
           code: CodeSegments.chipDemoAction,
         ),
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoChoiceChipTitle,
-          description:
-              GalleryLocalizations.of(context).demoChoiceChipDescription,
-          documentationUrl:
-              'https://api.flutter.dev/flutter/material/ChoiceChip-class.html',
+          title: localizations.demoChoiceChipTitle,
+          description: localizations.demoChoiceChipDescription,
+          documentationUrl: '$_docsBaseUrl/material/ChoiceChip-class.html',
           buildRoute: (_) => ChipDemo(type: ChipDemoType.choice),
           code: CodeSegments.chipDemoChoice,
         ),
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoFilterChipTitle,
-          description:
-              GalleryLocalizations.of(context).demoFilterChipDescription,
-          documentationUrl:
-              'https://api.flutter.dev/flutter/material/FilterChip-class.html',
+          title: localizations.demoFilterChipTitle,
+          description: localizations.demoFilterChipDescription,
+          documentationUrl: '$_docsBaseUrl/material/FilterChip-class.html',
           buildRoute: (_) => ChipDemo(type: ChipDemoType.filter),
           code: CodeSegments.chipDemoFilter,
         ),
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoInputChipTitle,
-          description:
-              GalleryLocalizations.of(context).demoInputChipDescription,
-          documentationUrl:
-              'https://api.flutter.dev/flutter/material/InputChip-class.html',
+          title: localizations.demoInputChipTitle,
+          description: localizations.demoInputChipDescription,
+          documentationUrl: '$_docsBaseUrl/material/InputChip-class.html',
           buildRoute: (_) => ChipDemo(type: ChipDemoType.input),
           code: CodeSegments.chipDemoInput,
         ),
       ],
     ),
     GalleryDemo(
-      title: GalleryLocalizations.of(context).demoDialogTitle,
+      title: localizations.demoDialogTitle,
       icon: GalleryIcons.dialogs,
-      subtitle: GalleryLocalizations.of(context).demoDialogSubtitle,
+      subtitle: localizations.demoDialogSubtitle,
       configurations: [
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoAlertDialogTitle,
-          description:
-              GalleryLocalizations.of(context).demoAlertDialogDescription,
-          documentationUrl:
-              'https://api.flutter.dev/flutter/material/AlertDialog-class.html',
+          title: localizations.demoAlertDialogTitle,
+          description: localizations.demoAlertDialogDescription,
+          documentationUrl: '$_docsBaseUrl/material/AlertDialog-class.html',
           buildRoute: (_) => DialogDemo(type: DialogDemoType.alert),
           code: CodeSegments.dialogDemo,
         ),
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoAlertTitleDialogTitle,
-          description:
-              GalleryLocalizations.of(context).demoAlertDialogDescription,
-          documentationUrl:
-              'https://api.flutter.dev/flutter/material/AlertDialog-class.html',
+          title: localizations.demoAlertTitleDialogTitle,
+          description: localizations.demoAlertDialogDescription,
+          documentationUrl: '$_docsBaseUrl/material/AlertDialog-class.html',
           buildRoute: (_) => DialogDemo(type: DialogDemoType.alertTitle),
           code: CodeSegments.dialogDemo,
         ),
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoSimpleDialogTitle,
-          description:
-              GalleryLocalizations.of(context).demoSimpleDialogDescription,
-          documentationUrl:
-              'https://api.flutter.dev/flutter/material/SimpleDialog-class.html',
+          title: localizations.demoSimpleDialogTitle,
+          description: localizations.demoSimpleDialogDescription,
+          documentationUrl: '$_docsBaseUrl/material/SimpleDialog-class.html',
           buildRoute: (_) => DialogDemo(type: DialogDemoType.simple),
           code: CodeSegments.dialogDemo,
         ),
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoFullscreenDialogTitle,
-          description:
-              GalleryLocalizations.of(context).demoFullscreenDialogDescription,
+          title: localizations.demoFullscreenDialogTitle,
+          description: localizations.demoFullscreenDialogDescription,
           documentationUrl:
-              'https://api.flutter.dev/flutter/widgets/PageRoute/fullscreenDialog.html',
+              '$_docsBaseUrl/widgets/PageRoute/fullscreenDialog.html',
           buildRoute: (_) => DialogDemo(type: DialogDemoType.fullscreen),
           code: CodeSegments.dialogDemo,
         ),
       ],
     ),
     GalleryDemo(
-      title: GalleryLocalizations.of(context).demoGridListsTitle,
+      title: localizations.demoGridListsTitle,
       icon: GalleryIcons.gridOn,
-      subtitle: GalleryLocalizations.of(context).demoGridListsSubtitle,
+      subtitle: localizations.demoGridListsSubtitle,
       configurations: [
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoGridListsImageOnlyTitle,
-          description:
-              GalleryLocalizations.of(context).demoGridListsDescription,
-          documentationUrl:
-              'https://api.flutter.dev/flutter/widgets/GridView-class.html',
+          title: localizations.demoGridListsImageOnlyTitle,
+          description: localizations.demoGridListsDescription,
+          documentationUrl: '$_docsBaseUrl/widgets/GridView-class.html',
           buildRoute: (context) =>
               GridListDemo(type: GridListDemoType.imageOnly),
           code: CodeSegments.gridListsDemo,
         ),
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoGridListsHeaderTitle,
-          description:
-              GalleryLocalizations.of(context).demoGridListsDescription,
-          documentationUrl:
-              'https://api.flutter.dev/flutter/widgets/GridView-class.html',
+          title: localizations.demoGridListsHeaderTitle,
+          description: localizations.demoGridListsDescription,
+          documentationUrl: '$_docsBaseUrl/widgets/GridView-class.html',
           buildRoute: (context) => GridListDemo(type: GridListDemoType.header),
           code: CodeSegments.gridListsDemo,
         ),
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoGridListsFooterTitle,
-          description:
-              GalleryLocalizations.of(context).demoGridListsDescription,
-          documentationUrl:
-              'https://api.flutter.dev/flutter/widgets/GridView-class.html',
+          title: localizations.demoGridListsFooterTitle,
+          description: localizations.demoGridListsDescription,
+          documentationUrl: '$_docsBaseUrl/widgets/GridView-class.html',
           buildRoute: (context) => GridListDemo(type: GridListDemoType.footer),
           code: CodeSegments.gridListsDemo,
         ),
       ],
     ),
     GalleryDemo(
-      title: GalleryLocalizations.of(context).demoListsTitle,
+      title: localizations.demoListsTitle,
       icon: GalleryIcons.listAlt,
-      subtitle: GalleryLocalizations.of(context).demoListsSubtitle,
+      subtitle: localizations.demoListsSubtitle,
       configurations: [
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoOneLineListsTitle,
-          description: GalleryLocalizations.of(context).demoListsDescription,
-          documentationUrl:
-              'https://api.flutter.dev/flutter/material/ListTile-class.html',
+          title: localizations.demoOneLineListsTitle,
+          description: localizations.demoListsDescription,
+          documentationUrl: '$_docsBaseUrl/material/ListTile-class.html',
           buildRoute: (context) => ListDemo(type: ListDemoType.oneLine),
           code: CodeSegments.listDemo,
         ),
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoTwoLineListsTitle,
-          description: GalleryLocalizations.of(context).demoListsDescription,
-          documentationUrl:
-              'https://api.flutter.dev/flutter/material/ListTile-class.html',
+          title: localizations.demoTwoLineListsTitle,
+          description: localizations.demoListsDescription,
+          documentationUrl: '$_docsBaseUrl/material/ListTile-class.html',
           buildRoute: (context) => ListDemo(type: ListDemoType.twoLine),
           code: CodeSegments.listDemo,
         ),
       ],
     ),
     GalleryDemo(
-      title: GalleryLocalizations.of(context).demoMenuTitle,
+      title: localizations.demoMenuTitle,
       icon: GalleryIcons.moreVert,
-      subtitle: GalleryLocalizations.of(context).demoMenuSubtitle,
+      subtitle: localizations.demoMenuSubtitle,
       configurations: [
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoContextMenuTitle,
-          description: GalleryLocalizations.of(context).demoMenuDescription,
-          documentationUrl:
-              'https://api.flutter.dev/flutter/material/PopupMenuItem-class.html',
+          title: localizations.demoContextMenuTitle,
+          description: localizations.demoMenuDescription,
+          documentationUrl: '$_docsBaseUrl/material/PopupMenuItem-class.html',
           buildRoute: (context) => MenuDemo(
             type: MenuDemoType.contextMenu,
           ),
           code: CodeSegments.menuDemoContext,
         ),
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoSectionedMenuTitle,
-          description: GalleryLocalizations.of(context).demoMenuDescription,
-          documentationUrl:
-              'https://api.flutter.dev/flutter/material/PopupMenuItem-class.html',
+          title: localizations.demoSectionedMenuTitle,
+          description: localizations.demoMenuDescription,
+          documentationUrl: '$_docsBaseUrl/material/PopupMenuItem-class.html',
           buildRoute: (context) => MenuDemo(
             type: MenuDemoType.sectionedMenu,
           ),
           code: CodeSegments.menuDemoSectioned,
         ),
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoChecklistMenuTitle,
-          description: GalleryLocalizations.of(context).demoMenuDescription,
+          title: localizations.demoChecklistMenuTitle,
+          description: localizations.demoMenuDescription,
           documentationUrl:
-              'https://api.flutter.dev/flutter/material/CheckedPopupMenuItem-class.html',
+              '$_docsBaseUrl/material/CheckedPopupMenuItem-class.html',
           buildRoute: (context) => MenuDemo(
             type: MenuDemoType.checklistMenu,
           ),
           code: CodeSegments.menuDemoChecklist,
         ),
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoSimpleMenuTitle,
-          description: GalleryLocalizations.of(context).demoMenuDescription,
-          documentationUrl:
-              'https://api.flutter.dev/flutter/material/PopupMenuItem-class.html',
+          title: localizations.demoSimpleMenuTitle,
+          description: localizations.demoMenuDescription,
+          documentationUrl: '$_docsBaseUrl/material/PopupMenuItem-class.html',
           buildRoute: (context) => MenuDemo(
             type: MenuDemoType.simpleMenu,
           ),
@@ -388,29 +349,25 @@ List<GalleryDemo> materialDemos(BuildContext context) {
       ],
     ),
     GalleryDemo(
-      title: GalleryLocalizations.of(context).demoProgressIndicatorTitle,
+      title: localizations.demoProgressIndicatorTitle,
       icon: GalleryIcons.progressActivity,
-      subtitle: GalleryLocalizations.of(context).demoProgressIndicatorSubtitle,
+      subtitle: localizations.demoProgressIndicatorSubtitle,
       configurations: [
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context)
-              .demoCircularProgressIndicatorTitle,
-          description: GalleryLocalizations.of(context)
-              .demoCircularProgressIndicatorDescription,
+          title: localizations.demoCircularProgressIndicatorTitle,
+          description: localizations.demoCircularProgressIndicatorDescription,
           documentationUrl:
-              'https://api.flutter.dev/flutter/material/CircularProgressIndicator-class.html',
+              '$_docsBaseUrl/material/CircularProgressIndicator-class.html',
           buildRoute: (context) => ProgressIndicatorDemo(
             type: ProgressIndicatorDemoType.circular,
           ),
           code: CodeSegments.progressIndicatorsDemo,
         ),
         GalleryDemoConfiguration(
-          title:
-              GalleryLocalizations.of(context).demoLinearProgressIndicatorTitle,
-          description: GalleryLocalizations.of(context)
-              .demoLinearProgressIndicatorDescription,
+          title: localizations.demoLinearProgressIndicatorTitle,
+          description: localizations.demoLinearProgressIndicatorDescription,
           documentationUrl:
-              'https://api.flutter.dev/flutter/material/LinearProgressIndicator-class.html',
+              '$_docsBaseUrl/material/LinearProgressIndicator-class.html',
           buildRoute: (context) => ProgressIndicatorDemo(
             type: ProgressIndicatorDemoType.linear,
           ),
@@ -419,41 +376,32 @@ List<GalleryDemo> materialDemos(BuildContext context) {
       ],
     ),
     GalleryDemo(
-      title: GalleryLocalizations.of(context).demoSelectionControlsTitle,
+      title: localizations.demoSelectionControlsTitle,
       icon: GalleryIcons.checkBox,
-      subtitle: GalleryLocalizations.of(context).demoSelectionControlsSubtitle,
+      subtitle: localizations.demoSelectionControlsSubtitle,
       configurations: [
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context)
-              .demoSelectionControlsCheckboxTitle,
-          description: GalleryLocalizations.of(context)
-              .demoSelectionControlsCheckboxDescription,
-          documentationUrl:
-              'https://api.flutter.dev/flutter/material/Checkbox-class.html',
+          title: localizations.demoSelectionControlsCheckboxTitle,
+          description: localizations.demoSelectionControlsCheckboxDescription,
+          documentationUrl: '$_docsBaseUrl/material/Checkbox-class.html',
           buildRoute: (context) => SelectionControlsDemo(
             type: SelectionControlsDemoType.checkbox,
           ),
           code: CodeSegments.selectionControlsDemoCheckbox,
         ),
         GalleryDemoConfiguration(
-          title:
-              GalleryLocalizations.of(context).demoSelectionControlsRadioTitle,
-          description: GalleryLocalizations.of(context)
-              .demoSelectionControlsRadioDescription,
-          documentationUrl:
-              'https://api.flutter.dev/flutter/material/Radio-class.html',
+          title: localizations.demoSelectionControlsRadioTitle,
+          description: localizations.demoSelectionControlsRadioDescription,
+          documentationUrl: '$_docsBaseUrl/material/Radio-class.html',
           buildRoute: (context) => SelectionControlsDemo(
             type: SelectionControlsDemoType.radio,
           ),
           code: CodeSegments.selectionControlsDemoRadio,
         ),
         GalleryDemoConfiguration(
-          title:
-              GalleryLocalizations.of(context).demoSelectionControlsSwitchTitle,
-          description: GalleryLocalizations.of(context)
-              .demoSelectionControlsSwitchDescription,
-          documentationUrl:
-              'https://api.flutter.dev/flutter/material/Switch-class.html',
+          title: localizations.demoSelectionControlsSwitchTitle,
+          description: localizations.demoSelectionControlsSwitchDescription,
+          documentationUrl: '$_docsBaseUrl/material/Switch-class.html',
           buildRoute: (context) => SelectionControlsDemo(
             type: SelectionControlsDemoType.switches,
           ),
@@ -462,34 +410,29 @@ List<GalleryDemo> materialDemos(BuildContext context) {
       ],
     ),
     GalleryDemo(
-      title: GalleryLocalizations.of(context).demoSlidersTitle,
+      title: localizations.demoSlidersTitle,
       icon: GalleryIcons.sliders,
-      subtitle: GalleryLocalizations.of(context).demoSlidersSubtitle,
+      subtitle: localizations.demoSlidersSubtitle,
       configurations: [
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoSlidersTitle,
-          description: GalleryLocalizations.of(context).demoSlidersDescription,
-          documentationUrl:
-              'https://api.flutter.dev/flutter/material/Slider-class.html',
+          title: localizations.demoSlidersTitle,
+          description: localizations.demoSlidersDescription,
+          documentationUrl: '$_docsBaseUrl/material/Slider-class.html',
           buildRoute: (context) => SlidersDemo(type: SlidersDemoType.sliders),
           code: CodeSegments.slidersDemo,
         ),
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoRangeSlidersTitle,
-          description:
-              GalleryLocalizations.of(context).demoRangeSlidersDescription,
-          documentationUrl:
-              'https://api.flutter.dev/flutter/material/RangeSlider-class.html',
+          title: localizations.demoRangeSlidersTitle,
+          description: localizations.demoRangeSlidersDescription,
+          documentationUrl: '$_docsBaseUrl/material/RangeSlider-class.html',
           buildRoute: (context) =>
               SlidersDemo(type: SlidersDemoType.rangeSliders),
           code: CodeSegments.rangeSlidersDemo,
         ),
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoCustomSlidersTitle,
-          description:
-              GalleryLocalizations.of(context).demoCustomSlidersDescription,
-          documentationUrl:
-              'https://api.flutter.dev/flutter/material/SliderTheme-class.html',
+          title: localizations.demoCustomSlidersTitle,
+          description: localizations.demoCustomSlidersDescription,
+          documentationUrl: '$_docsBaseUrl/material/SliderTheme-class.html',
           buildRoute: (context) =>
               SlidersDemo(type: SlidersDemoType.customSliders),
           code: CodeSegments.customSlidersDemo,
@@ -497,62 +440,56 @@ List<GalleryDemo> materialDemos(BuildContext context) {
       ],
     ),
     GalleryDemo(
-      title: GalleryLocalizations.of(context).demoSnackbarsTitle,
+      title: localizations.demoSnackbarsTitle,
       icon: GalleryIcons.snackbar,
-      subtitle: GalleryLocalizations.of(context).demoSnackbarsSubtitle,
+      subtitle: localizations.demoSnackbarsSubtitle,
       configurations: [
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoSnackbarsTitle,
-          description:
-              GalleryLocalizations.of(context).demoSnackbarsDescription,
-          documentationUrl:
-              'https://api.flutter.dev/flutter/material/SnackBar-class.html',
+          title: localizations.demoSnackbarsTitle,
+          description: localizations.demoSnackbarsDescription,
+          documentationUrl: '$_docsBaseUrl/material/SnackBar-class.html',
           buildRoute: (context) => SnackbarsDemo(),
           code: CodeSegments.snackbarsDemo,
         ),
       ],
     ),
     GalleryDemo(
-      title: GalleryLocalizations.of(context).demoTabsTitle,
+      title: localizations.demoTabsTitle,
       icon: GalleryIcons.tabs,
-      subtitle: GalleryLocalizations.of(context).demoTabsSubtitle,
+      subtitle: localizations.demoTabsSubtitle,
       configurations: [
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoTabsTitle,
-          description: GalleryLocalizations.of(context).demoTabsDescription,
-          documentationUrl:
-              'https://api.flutter.dev/flutter/material/TabBarView-class.html',
+          title: localizations.demoTabsTitle,
+          description: localizations.demoTabsDescription,
+          documentationUrl: '$_docsBaseUrl/material/TabBarView-class.html',
           buildRoute: (context) => TabsDemo(),
           code: CodeSegments.tabsDemo,
         ),
       ],
     ),
     GalleryDemo(
-      title: GalleryLocalizations.of(context).demoTextFieldTitle,
+      title: localizations.demoTextFieldTitle,
       icon: GalleryIcons.textFieldsAlt,
-      subtitle: GalleryLocalizations.of(context).demoTextFieldSubtitle,
+      subtitle: localizations.demoTextFieldSubtitle,
       configurations: [
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoTextFieldTitle,
-          description:
-              GalleryLocalizations.of(context).demoTextFieldDescription,
-          documentationUrl:
-              'https://api.flutter.dev/flutter/material/TextField-class.html',
+          title: localizations.demoTextFieldTitle,
+          description: localizations.demoTextFieldDescription,
+          documentationUrl: '$_docsBaseUrl/material/TextField-class.html',
           buildRoute: (_) => TextFieldDemo(),
           code: CodeSegments.textFieldDemo,
         ),
       ],
     ),
     GalleryDemo(
-      title: GalleryLocalizations.of(context).demoTooltipTitle,
+      title: localizations.demoTooltipTitle,
       icon: GalleryIcons.tooltip,
-      subtitle: GalleryLocalizations.of(context).demoTooltipSubtitle,
+      subtitle: localizations.demoTooltipSubtitle,
       configurations: [
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoTooltipTitle,
-          description: GalleryLocalizations.of(context).demoTooltipDescription,
-          documentationUrl:
-              'https://api.flutter.dev/flutter/material/Tooltip-class.html',
+          title: localizations.demoTooltipTitle,
+          description: localizations.demoTooltipDescription,
+          documentationUrl: '$_docsBaseUrl/material/Tooltip-class.html',
           buildRoute: (_) => TooltipDemo(),
           code: CodeSegments.tooltipDemo,
         ),
@@ -562,78 +499,67 @@ List<GalleryDemo> materialDemos(BuildContext context) {
 }
 
 List<GalleryDemo> cupertinoDemos(BuildContext context) {
+  final localizations = GalleryLocalizations.of(context);
   return [
     GalleryDemo(
-      title:
-          GalleryLocalizations.of(context).demoCupertinoActivityIndicatorTitle,
+      title: localizations.demoCupertinoActivityIndicatorTitle,
       icon: GalleryIcons.cupertinoProgress,
-      subtitle: GalleryLocalizations.of(context)
-          .demoCupertinoActivityIndicatorSubtitle,
+      subtitle: localizations.demoCupertinoActivityIndicatorSubtitle,
       configurations: [
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context)
-              .demoCupertinoActivityIndicatorTitle,
-          description: GalleryLocalizations.of(context)
-              .demoCupertinoActivityIndicatorDescription,
+          title: localizations.demoCupertinoActivityIndicatorTitle,
+          description: localizations.demoCupertinoActivityIndicatorDescription,
           documentationUrl:
-              'https://api.flutter.dev/flutter/cupertino/CupertinoActivityIndicator-class.html',
+              '$_docsBaseUrl/cupertino/CupertinoActivityIndicator-class.html',
           buildRoute: (_) => CupertinoProgressIndicatorDemo(),
           code: CodeSegments.cupertinoActivityIndicatorDemo,
         ),
       ],
     ),
     GalleryDemo(
-      title: GalleryLocalizations.of(context).demoCupertinoAlertsTitle,
+      title: localizations.demoCupertinoAlertsTitle,
       icon: GalleryIcons.dialogs,
-      subtitle: GalleryLocalizations.of(context).demoCupertinoAlertsSubtitle,
+      subtitle: localizations.demoCupertinoAlertsSubtitle,
       configurations: [
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoCupertinoAlertTitle,
-          description:
-              GalleryLocalizations.of(context).demoCupertinoAlertDescription,
+          title: localizations.demoCupertinoAlertTitle,
+          description: localizations.demoCupertinoAlertDescription,
           documentationUrl:
-              'https://api.flutter.dev/flutter/cupertino/CupertinoAlertDialog-class.html',
+              '$_docsBaseUrl/cupertino/CupertinoAlertDialog-class.html',
           buildRoute: (_) => CupertinoAlertDemo(type: AlertDemoType.alert),
           code: CodeSegments.cupertinoAlertDemo,
         ),
         GalleryDemoConfiguration(
-          title:
-              GalleryLocalizations.of(context).demoCupertinoAlertWithTitleTitle,
-          description:
-              GalleryLocalizations.of(context).demoCupertinoAlertDescription,
+          title: localizations.demoCupertinoAlertWithTitleTitle,
+          description: localizations.demoCupertinoAlertDescription,
           documentationUrl:
-              'https://api.flutter.dev/flutter/cupertino/CupertinoAlertDialog-class.html',
+              '$_docsBaseUrl/cupertino/CupertinoAlertDialog-class.html',
           buildRoute: (_) => CupertinoAlertDemo(type: AlertDemoType.alertTitle),
           code: CodeSegments.cupertinoAlertDemo,
         ),
         GalleryDemoConfiguration(
-          title:
-              GalleryLocalizations.of(context).demoCupertinoAlertButtonsTitle,
-          description:
-              GalleryLocalizations.of(context).demoCupertinoAlertDescription,
+          title: localizations.demoCupertinoAlertButtonsTitle,
+          description: localizations.demoCupertinoAlertDescription,
           documentationUrl:
-              'https://api.flutter.dev/flutter/cupertino/CupertinoAlertDialog-class.html',
+              '$_docsBaseUrl/cupertino/CupertinoAlertDialog-class.html',
           buildRoute: (_) =>
               CupertinoAlertDemo(type: AlertDemoType.alertButtons),
           code: CodeSegments.cupertinoAlertDemo,
         ),
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context)
-              .demoCupertinoAlertButtonsOnlyTitle,
-          description:
-              GalleryLocalizations.of(context).demoCupertinoAlertDescription,
+          title: localizations.demoCupertinoAlertButtonsOnlyTitle,
+          description: localizations.demoCupertinoAlertDescription,
           documentationUrl:
-              'https://api.flutter.dev/flutter/cupertino/CupertinoAlertDialog-class.html',
+              '$_docsBaseUrl/cupertino/CupertinoAlertDialog-class.html',
           buildRoute: (_) =>
               CupertinoAlertDemo(type: AlertDemoType.alertButtonsOnly),
           code: CodeSegments.cupertinoAlertDemo,
         ),
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoCupertinoActionSheetTitle,
-          description: GalleryLocalizations.of(context)
-              .demoCupertinoActionSheetDescription,
+          title: localizations.demoCupertinoActionSheetTitle,
+          description: localizations.demoCupertinoActionSheetDescription,
           documentationUrl:
-              'https://api.flutter.dev/flutter/cupertino/CupertinoActionSheet-class.html',
+              '$_docsBaseUrl/cupertino/CupertinoActionSheet-class.html',
           buildRoute: (_) =>
               CupertinoAlertDemo(type: AlertDemoType.actionSheet),
           code: CodeSegments.cupertinoAlertDemo,
@@ -641,120 +567,105 @@ List<GalleryDemo> cupertinoDemos(BuildContext context) {
       ],
     ),
     GalleryDemo(
-      title: GalleryLocalizations.of(context).demoCupertinoButtonsTitle,
+      title: localizations.demoCupertinoButtonsTitle,
       icon: GalleryIcons.genericButtons,
-      subtitle: GalleryLocalizations.of(context).demoCupertinoButtonsSubtitle,
+      subtitle: localizations.demoCupertinoButtonsSubtitle,
       configurations: [
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoCupertinoButtonsTitle,
-          description:
-              GalleryLocalizations.of(context).demoCupertinoButtonsDescription,
+          title: localizations.demoCupertinoButtonsTitle,
+          description: localizations.demoCupertinoButtonsDescription,
           documentationUrl:
-              'https://api.flutter.dev/flutter/cupertino/CupertinoButton-class.html',
+              '$_docsBaseUrl/cupertino/CupertinoButton-class.html',
           buildRoute: (_) => CupertinoButtonDemo(),
           code: CodeSegments.cupertinoButtonDemo,
         ),
       ],
     ),
     GalleryDemo(
-      title: GalleryLocalizations.of(context).demoCupertinoNavigationBarTitle,
+      title: localizations.demoCupertinoNavigationBarTitle,
       icon: GalleryIcons.bottomSheetPersistent,
-      subtitle:
-          GalleryLocalizations.of(context).demoCupertinoNavigationBarSubtitle,
+      subtitle: localizations.demoCupertinoNavigationBarSubtitle,
       configurations: [
         GalleryDemoConfiguration(
-          title:
-              GalleryLocalizations.of(context).demoCupertinoNavigationBarTitle,
-          description: GalleryLocalizations.of(context)
-              .demoCupertinoNavigationBarDescription,
+          title: localizations.demoCupertinoNavigationBarTitle,
+          description: localizations.demoCupertinoNavigationBarDescription,
           documentationUrl:
-              'https://api.flutter.dev/flutter/cupertino/CupertinoNavigationBar-class.html',
+              '$_docsBaseUrl/cupertino/CupertinoNavigationBar-class.html',
           buildRoute: (_) => CupertinoNavigationBarDemo(),
           code: CodeSegments.cupertinoNavigationBarDemo,
         ),
       ],
     ),
     GalleryDemo(
-      title: GalleryLocalizations.of(context).demoCupertinoPullToRefreshTitle,
+      title: localizations.demoCupertinoPullToRefreshTitle,
       icon: GalleryIcons.cupertinoPullToRefresh,
-      subtitle:
-          GalleryLocalizations.of(context).demoCupertinoPullToRefreshSubtitle,
+      subtitle: localizations.demoCupertinoPullToRefreshSubtitle,
       configurations: [
         GalleryDemoConfiguration(
-          title:
-              GalleryLocalizations.of(context).demoCupertinoPullToRefreshTitle,
-          description: GalleryLocalizations.of(context)
-              .demoCupertinoPullToRefreshDescription,
+          title: localizations.demoCupertinoPullToRefreshTitle,
+          description: localizations.demoCupertinoPullToRefreshDescription,
           documentationUrl:
-              'https://api.flutter.dev/flutter/cupertino/CupertinoSliverRefreshControl-class.html',
+              '$_docsBaseUrl/cupertino/CupertinoSliverRefreshControl-class.html',
           buildRoute: (_) => CupertinoRefreshControlDemo(),
           code: CodeSegments.cupertinoRefreshDemo,
         ),
       ],
     ),
     GalleryDemo(
-      title:
-          GalleryLocalizations.of(context).demoCupertinoSegmentedControlTitle,
+      title: localizations.demoCupertinoSegmentedControlTitle,
       icon: GalleryIcons.tabs,
-      subtitle: GalleryLocalizations.of(context)
-          .demoCupertinoSegmentedControlSubtitle,
+      subtitle: localizations.demoCupertinoSegmentedControlSubtitle,
       configurations: [
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context)
-              .demoCupertinoSegmentedControlTitle,
-          description: GalleryLocalizations.of(context)
-              .demoCupertinoSegmentedControlDescription,
+          title: localizations.demoCupertinoSegmentedControlTitle,
+          description: localizations.demoCupertinoSegmentedControlDescription,
           documentationUrl:
-              'https://api.flutter.dev/flutter/cupertino/CupertinoSegmentedControl-class.html',
+              '$_docsBaseUrl/cupertino/CupertinoSegmentedControl-class.html',
           buildRoute: (_) => CupertinoSegmentedControlDemo(),
           code: CodeSegments.cupertinoSegmentedControlDemo,
         ),
       ],
     ),
     GalleryDemo(
-      title: GalleryLocalizations.of(context).demoCupertinoSliderTitle,
+      title: localizations.demoCupertinoSliderTitle,
       icon: GalleryIcons.sliders,
-      subtitle: GalleryLocalizations.of(context).demoCupertinoSliderSubtitle,
+      subtitle: localizations.demoCupertinoSliderSubtitle,
       configurations: [
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoCupertinoSliderTitle,
-          description:
-              GalleryLocalizations.of(context).demoCupertinoSliderDescription,
+          title: localizations.demoCupertinoSliderTitle,
+          description: localizations.demoCupertinoSliderDescription,
           documentationUrl:
-              'https://api.flutter.dev/flutter/cupertino/CupertinoSlider-class.html',
+              '$_docsBaseUrl/cupertino/CupertinoSlider-class.html',
           buildRoute: (_) => CupertinoSliderDemo(),
           code: CodeSegments.cupertinoSliderDemo,
         ),
       ],
     ),
     GalleryDemo(
-      title: GalleryLocalizations.of(context).demoSelectionControlsSwitchTitle,
+      title: localizations.demoSelectionControlsSwitchTitle,
       icon: GalleryIcons.cupertinoSwitch,
-      subtitle: GalleryLocalizations.of(context).demoCupertinoSwitchSubtitle,
+      subtitle: localizations.demoCupertinoSwitchSubtitle,
       configurations: [
         GalleryDemoConfiguration(
-          title:
-              GalleryLocalizations.of(context).demoSelectionControlsSwitchTitle,
-          description:
-              GalleryLocalizations.of(context).demoCupertinoSwitchDescription,
+          title: localizations.demoSelectionControlsSwitchTitle,
+          description: localizations.demoCupertinoSwitchDescription,
           documentationUrl:
-              'https://api.flutter.dev/flutter/cupertino/CupertinoSwitch-class.html',
+              '$_docsBaseUrl/cupertino/CupertinoSwitch-class.html',
           buildRoute: (_) => CupertinoSwitchDemo(),
           code: CodeSegments.cupertinoSwitchDemo,
         ),
       ],
     ),
     GalleryDemo(
-      title: GalleryLocalizations.of(context).demoCupertinoTabBarTitle,
+      title: localizations.demoCupertinoTabBarTitle,
       icon: GalleryIcons.bottomNavigation,
-      subtitle: GalleryLocalizations.of(context).demoCupertinoTabBarSubtitle,
+      subtitle: localizations.demoCupertinoTabBarSubtitle,
       configurations: [
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoCupertinoTabBarTitle,
-          description:
-              GalleryLocalizations.of(context).demoCupertinoTabBarDescription,
+          title: localizations.demoCupertinoTabBarTitle,
+          description: localizations.demoCupertinoTabBarDescription,
           documentationUrl:
-              'https://api.flutter.dev/flutter/cupertino/CupertinoTabBar-class.html',
+              '$_docsBaseUrl/cupertino/CupertinoTabBar-class.html',
           buildRoute: (_) => CupertinoTabBarDemo(),
           code: CodeSegments.cupertinoNavigationDemo,
         ),
@@ -764,33 +675,31 @@ List<GalleryDemo> cupertinoDemos(BuildContext context) {
 }
 
 List<GalleryDemo> referenceDemos(BuildContext context) {
+  final localizations = GalleryLocalizations.of(context);
   return [
     GalleryDemo(
-      title: GalleryLocalizations.of(context).demoColorsTitle,
+      title: localizations.demoColorsTitle,
       icon: GalleryIcons.colors,
-      subtitle: GalleryLocalizations.of(context).demoColorsSubtitle,
+      subtitle: localizations.demoColorsSubtitle,
       configurations: [
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoColorsTitle,
-          description: GalleryLocalizations.of(context).demoColorsDescription,
-          documentationUrl:
-              'https://api.flutter.dev/flutter/material/MaterialColor-class.html',
+          title: localizations.demoColorsTitle,
+          description: localizations.demoColorsDescription,
+          documentationUrl: '$_docsBaseUrl/material/MaterialColor-class.html',
           buildRoute: (_) => ColorsDemo(),
           code: CodeSegments.colorsDemo,
         ),
       ],
     ),
     GalleryDemo(
-      title: GalleryLocalizations.of(context).demoTypographyTitle,
+      title: localizations.demoTypographyTitle,
       icon: GalleryIcons.customTypography,
-      subtitle: GalleryLocalizations.of(context).demoTypographySubtitle,
+      subtitle: localizations.demoTypographySubtitle,
       configurations: [
         GalleryDemoConfiguration(
-          title: GalleryLocalizations.of(context).demoTypographyTitle,
-          description:
-              GalleryLocalizations.of(context).demoTypographyDescription,
-          documentationUrl:
-              'https://api.flutter.dev/flutter/material/TextTheme-class.html',
+          title: localizations.demoTypographyTitle,
+          description: localizations.demoTypographyDescription,
+          documentationUrl: '$_docsBaseUrl/material/TextTheme-class.html',
           buildRoute: (_) => TypographyDemo(),
           code: CodeSegments.typographyDemo,
         ),