Fixed a bug in the example

Signed-off-by: Hans Kokx <hans.d.kokx@gmail.com>

example/lib/main.dart

@@ -152,8 +152,11 @@ class _ArcaneLoggingExampleState extends State<ArcaneLoggingExample> {
       builder: (context, enabledFeatures, _) {
         return Padding(
           padding: const EdgeInsets.all(16.0),
+          child: Card(
             child: SizedBox(
-            height: 200,
+              height: MediaQuery.sizeOf(context).height / 2,
+              child: Padding(
+                padding: const EdgeInsets.all(8.0),
                 child: Column(
                   crossAxisAlignment: CrossAxisAlignment.start,
                   children: [
@@ -186,6 +189,8 @@ class _ArcaneLoggingExampleState extends State<ArcaneLoggingExample> {
                   ],
                 ),
               ),
+            ),
+          ),
         );
       },
     );
@@ -544,6 +549,11 @@ class ArcaneServicesExample extends StatelessWidget {
   Widget build(BuildContext context) {
     final FavoriteColorService? service =
         ArcaneServiceProvider.serviceOfType<FavoriteColorService>(context);
+    final ValueNotifier<MaterialColor?> notifier =
+        service?.notifier ?? ValueNotifier(null);
+    return ValueListenableBuilder(
+      valueListenable: notifier,
+      builder: (context, color, _) {
         return Card(
           child: Padding(
             padding: const EdgeInsets.all(8.0),
@@ -555,16 +565,8 @@ class ArcaneServicesExample extends StatelessWidget {
                   "Services",
                   style: Theme.of(context).textTheme.headlineSmall,
                 ),
-            ValueListenableBuilder(
+                Text(
-              valueListenable: ArcaneService.ofType<FavoriteColorService>(
-                    context,
-                  )?.notifier ??
-                  ValueNotifier(null),
-              builder: (context, color, _) {
-                return Text(
                   color != null ? "Favorite color: ${color.name}" : "",
-                );
-              },
                 ),
                 ElevatedButton(
                   onPressed: () {
@@ -587,7 +589,9 @@ class ArcaneServicesExample extends StatelessWidget {
                       );
                     }
                   },
-              child: Text('${service == null ? 'Register' : 'Remove'} service'),
+                  child: Text(
+                    '${service == null ? 'Register' : 'Remove'} service',
+                  ),
                 ),
                 SizedBox(
                   height: 20,
@@ -604,7 +608,14 @@ class ArcaneServicesExample extends StatelessWidget {
                           itemBuilder: (context, index) {
                             return InkWell(
                               onTap: () {
-                            service?.setMyFavoriteColor(colors[index]);
+                                if (service == null) {
+                                  Arcane.log(
+                                    "FavoriteColorService is not registered",
+                                  );
+                                  return;
+                                }
+
+                                service.setMyFavoriteColor(colors[index]);
                                 Arcane.log(
                                   "Set a color in FavoriteColorService",
                                   metadata: {
@@ -615,8 +626,7 @@ class ArcaneServicesExample extends StatelessWidget {
                               child: Container(
                                 decoration: BoxDecoration(
                                   color: colors[index],
-                              border: service?.myFavoriteColor?.name ==
+                                  border: color?.name == colors[index].name
-                                      colors[index].name
                                       ? Border.all(width: 2)
                                       : null,
                                 ),
@@ -637,5 +647,7 @@ class ArcaneServicesExample extends StatelessWidget {
             ),
           ),
         );
+      },
+    );
   }
 }