packages/wyatt_ui_kit/lib/src/components/bars/top_app_bar.dart

@@ -58,16 +58,15 @@ class TopAppBar extends TopAppBarComponent with $TopAppBarCWMixin {
             valueValidator: (value) => value?.isGradient,
             transform: (value) =>
                 LinearGradientHelper.fromNullableColors(value?.colors),
-            defaultValue: null,
           ),
           color: ThemeHelper.getThemeElement<MultiColor, Color>(
             [
               backgroundColor,
               context.themeExtension<TopBarThemeExtension>()?.backgroundColors,
+              MultiColor.single(Theme.of(context).appBarTheme.backgroundColor),
             ],
             valueValidator: (value) => value?.isColor,
             transform: (value) => value?.color,
-            defaultValue: Theme.of(context).appBarTheme.backgroundColor,
           ),
         ),
         child: Column(
@@ -88,10 +87,10 @@ class TopAppBar extends TopAppBarComponent with $TopAppBarCWMixin {
                 [
                   iconTheme,
                   context.themeExtension<TopBarThemeExtension>()?.iconTheme,
+                  Theme.of(context).iconTheme,
                 ],
                 valueValidator: (value) => value != null,
                 transform: (value) => value,
-                defaultValue: Theme.of(context).iconTheme,
               ),
               primary: primary ?? true,
               excludeHeaderSemantics: excludeHeaderSemantics ?? false,
@@ -100,12 +99,13 @@ class TopAppBar extends TopAppBarComponent with $TopAppBarCWMixin {
                 title?.data ?? '',
                 style: ThemeHelper.getThemeElement<TextStyle, TextStyle>(
                   [
+                    context.textTheme.titleLarge,
+                    context.themeExtension<TopBarThemeExtension>()?.titleStyle,
                     title?.style,
-                    context.themeExtension<TopBarThemeExtension>()?.titleStyle
                   ],
                   valueValidator: (value) => value != null,
+                  combine: (p0, p1) => p0?.merge(p1),
                   transform: (value) => value,
-                  defaultValue: context.textTheme.titleLarge,
                 ),
               ).toGradient(gradientColors: title?.gradientColors),
               leading: leading,
@@ -120,10 +120,10 @@ class TopAppBar extends TopAppBarComponent with $TopAppBarCWMixin {
                         .themeExtension<TopBarThemeExtension>()
                         ?.secondaryColor
                         ?.withOpacity(0.1),
+                    Theme.of(context).dividerColor,
                   ],
                   valueValidator: (value) => value != null,
                   transform: (value) => value,
-                  defaultValue: Theme.of(context).dividerColor,
                 ),
                 context: context,
                 tiles: expandedWidget!,

packages/wyatt_ui_kit/lib/src/components/bars/top_navigation_bar.dart

@@ -62,16 +62,15 @@ class TopNavigationBar extends TopNavigationBarComponent
             valueValidator: (value) => value?.isGradient,
             transform: (value) =>
                 LinearGradientHelper.fromNullableColors(value?.colors),
-            defaultValue: null,
           ),
           color: ThemeHelper.getThemeElement<MultiColor, Color>(
             [
               backgroundColor,
               context.themeExtension<TopBarThemeExtension>()?.backgroundColors,
+              MultiColor.single(Theme.of(context).appBarTheme.backgroundColor),
             ],
             valueValidator: (value) => value?.isColor,
             transform: (value) => value?.color,
-            defaultValue: Theme.of(context).appBarTheme.backgroundColor,
           ),
         ),
         child: AppBar(
@@ -90,10 +89,10 @@ class TopNavigationBar extends TopNavigationBarComponent
             [
               iconTheme,
               context.themeExtension<TopBarThemeExtension>()?.iconTheme,
+              Theme.of(context).iconTheme,
             ],
             valueValidator: (value) => value != null,
             transform: (value) => value,
-            defaultValue: Theme.of(context).iconTheme,
           ),
           primary: primary ?? true,
           excludeHeaderSemantics: excludeHeaderSemantics ?? false,

packages/wyatt_ui_kit/lib/src/components/bars/widgets/navigation_item.dart

@@ -41,11 +41,11 @@ class NavigationItem extends StatelessWidget {
                   [
                     context
                         .themeExtension<TopBarThemeExtension>()
-                        ?.secondaryColor
+                        ?.secondaryColor,
+                    Theme.of(context).primaryColor,
                   ],
                   valueValidator: (value) => value != null,
                   transform: (value) => value,
-                  defaultValue: Theme.of(context).primaryColor,
                 ),
               ),
             ),
@@ -56,14 +56,15 @@ class NavigationItem extends StatelessWidget {
                 item.data,
                 style: ThemeHelper.getThemeElement<TextStyle, TextStyle>(
                   [
-                    item.style,
+                    context.textTheme.titleMedium,
                     context
                         .themeExtension<TopBarThemeExtension>()
-                        ?.subTitleStyle
+                        ?.subTitleStyle,
+                    item.style,
                   ],
+                  combine: (value, element) => value?.merge(element),
                   valueValidator: (value) => value != null,
                   transform: (value) => value,
-                  defaultValue: context.textTheme.titleMedium,
                 ),
               ),
             ),

packages/wyatt_ui_kit/lib/src/components/cards/widgets/card_wrapper.dart

@@ -74,7 +74,6 @@ class CardWrapper extends StatelessWidget {
       ],
       valueValidator: (shadow) => shadow != null,
       transform: (shadow) => shadow,
-      defaultValue: null,
     );
     return (themeShadow != null) ? [themeShadow] : [];
   }
@@ -92,11 +91,9 @@ class CardWrapper extends StatelessWidget {
                     .extension<CardThemeExtension>()
                     ?.backgroundColors,
               ],
-              valueValidator: (multiColor) =>
-                  multiColor != null && multiColor.isGradient,
+              valueValidator: (multiColor) => multiColor?.isGradient,
               transform: (multiColor) =>
                   LinearGradientHelper.fromMultiColor(multiColor!),
-              defaultValue: null,
             ),
             color: ThemeHelper.getThemeElement<MultiColor, Color>(
               [
@@ -104,11 +101,11 @@ class CardWrapper extends StatelessWidget {
                 Theme.of(context)
                     .extension<CardThemeExtension>()
                     ?.backgroundColors,
+                MultiColor.single(Theme.of(context).cardColor),
               ],
               valueValidator: (multiColor) =>
                   multiColor != null && multiColor.isColor,
               transform: (multiColor) => multiColor?.color,
-              defaultValue: Theme.of(context).cardColor,
             ),
             border: ThemeHelper.getThemeElement<MultiColor, BoxBorder>(
               [
@@ -130,7 +127,6 @@ class CardWrapper extends StatelessWidget {
                   color: multiColor.color,
                 );
               },
-              defaultValue: null,
             ),
             boxShadow: _shadow(context),
           ),

packages/wyatt_ui_kit/lib/src/core/helpers/theme_helper.dart

@@ -16,26 +16,34 @@
 
 /// A helper class for getting theme elements.
 abstract class ThemeHelper {
-
   /// Gets a theme element from a list of styles.
   /// Styles are checked in order, and the first one that passes the
   /// [valueValidator] is returned.
-  /// If no style passes the [valueValidator], the [defaultValue] is returned.
-  /// If [styles] is null or empty, the [defaultValue] is returned.
   /// Style elements are transformed using the [transform] function.
+  ///
+  /// [styles]: A list of styles that need to be checked.
+  /// [transform]: A function that transforms each style element
+  /// to a [T] type.
+  /// [valueValidator]: An optional validation function that
+  /// determines if a style element is valid.
+  /// [combine]: A function that combines two [P] type objects to create
+  /// a new object.
+
   static T? getThemeElement<P, T>(
     List<P?>? styles, {
     required T? Function(P?)? transform,
-    required T? defaultValue,
     bool? Function(P?)? valueValidator,
+    P? Function(P?, P?)? combine,
   }) {
-    if (styles?.isNotEmpty ?? false) {
-      for (final element in styles!) {
-        if (valueValidator?.call(element) ?? false) {
-          return transform?.call(element);
-        }
-      }
-    }
-    return defaultValue;
+    final Iterable<P?>? validStyles = styles?.where(
+      (element) => valueValidator?.call(element) ?? (element != null),
+    );
+    return (validStyles?.isNotEmpty ?? false)
+        ? transform?.call(
+            validStyles?.reduce(
+              (value, element) => combine?.call(value, element) ?? value,
+            ),
+          )
+        : null;
   }
 }