Tony/163 consistent light theme mode

CHANGELOG.md

@@ -15,6 +15,7 @@ au](https://solidcommunity.au/docs/solidui)
 
 ## 0.1.0 First Release
 
++ Simplified light/dark theme management [0.0.24 20260116 tonypioneer]
 + Support custom folder structure [0.0.24 20260114 anusavid]
 + Default keyboard focus on LOGIN #160 [0.0.23 20260113 tonypioneer]
 + Updated solidpod dependency - writePod() #155 [0.0.22 20260113 dc]

example/lib/app.dart

@@ -55,7 +55,7 @@ class App extends StatelessWidget {
 
       home: const SolidLogin(
         image: AssetImage('assets/images/app_image.jpg'),
-        logo: AssetImage('assets/images/app_icon.jpg'),
+        logo: AssetImage('assets/images/app_icon.png'),
         customFolderPathList: [
           'customDir1',
           'customDir2',

example/lib/app_scaffold.dart

@@ -34,7 +34,7 @@ import 'package:solidui/solidui.dart';
 
 import 'constants/app.dart';
 import 'home.dart';
-import 'screens/settings_page.dart';
+import 'screens/sample_page.dart';
 
 final _scaffoldController = SolidScaffoldController();
 
@@ -73,18 +73,6 @@ class AppScaffold extends StatelessWidget {
             ''',
           child: SolidFile(),
         ),
-        SolidMenuItem(
-          icon: Icons.info,
-          title: 'About',
-          tooltip: '''
-
-            **About:** Tap here to learn more about this application.
-
-            ''',
-          child: Center(
-            child: Text('About Page', style: TextStyle(fontSize: 24)),
-          ),
-        ),
       ],
 
       // APP BAR.
@@ -105,18 +93,18 @@ class AppScaffold extends StatelessWidget {
 
         actions: [
           SolidAppBarAction(
-            icon: Icons.folder_open,
+            icon: Icons.folder,
             onPressed: () => _scaffoldController.navigateToSubpage(
               const SolidFile(),
             ),
             tooltip: 'Files',
           ),
           SolidAppBarAction(
-            icon: Icons.settings,
+            icon: Icons.article,
             onPressed: () => _scaffoldController.navigateToSubpage(
-              const SettingsPage(),
+              const SamplePage(),
             ),
-            tooltip: 'Settings',
+            tooltip: 'Sample Page',
           ),
         ],
       ),
@@ -134,7 +122,7 @@ class AppScaffold extends StatelessWidget {
       aboutConfig: SolidAboutConfig(
         applicationName: appTitle.split(' - ')[0],
         applicationIcon: Image.asset(
-          'assets/images/app_icon.jpg',
+          'assets/images/app_icon.png',
           width: 64,
           height: 64,
         ),

example/lib/screens/sample_page.dart

@@ -0,0 +1,91 @@
+/// Sample page - Demonstrates AppBar-only navigation pattern.
+///
+/// Copyright (C) 2026, Software Innovation Institute, ANU.
+///
+/// Licensed under the MIT License (the "License").
+///
+/// License: https://choosealicense.com/licenses/mit/.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+///
+/// Authors: Tony Chen
+
+library;
+
+import 'package:flutter/material.dart';
+
+/// Sample page widget demonstrating AppBar-only navigation.
+
+class SamplePage extends StatelessWidget {
+  const SamplePage({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    final theme = Theme.of(context);
+
+    return Center(
+      child: Card(
+        margin: const EdgeInsets.all(32.0),
+        child: Padding(
+          padding: const EdgeInsets.all(32.0),
+          child: Column(
+            mainAxisSize: MainAxisSize.min,
+            children: [
+              Icon(
+                Icons.article_outlined,
+                size: 64,
+                color: theme.colorScheme.primary,
+              ),
+              const SizedBox(height: 24),
+              Text(
+                'Sample Page',
+                style: theme.textTheme.headlineMedium?.copyWith(
+                  fontWeight: FontWeight.bold,
+                ),
+              ),
+              const SizedBox(height: 16),
+              Text(
+                'AppBar-Only Navigation Demo',
+                style: theme.textTheme.titleMedium?.copyWith(
+                  color: theme.colorScheme.primary,
+                ),
+              ),
+              const SizedBox(height: 32),
+              Container(
+                constraints: const BoxConstraints(maxWidth: 500),
+                child: Text(
+                  'The navigation buttons for this page are only placed on '
+                  'the app bar, so no buttons on the navigation rail will be '
+                  'highlighted when entering this page. In contrast, when '
+                  'the Files button on the app bar is clicked, the '
+                  'Files button on the navigation rail will be highlighted '
+                  'as well, since it is laid out in both places. This button '
+                  'also demonstrates the usage of the navigateToSubpage() '
+                  'function.',
+                  style: theme.textTheme.bodyLarge,
+                  textAlign: TextAlign.left,
+                ),
+              ),
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+}