Fix empty nav menu

src/Calculator.Shared/CalcManager/CalculatorList.cs

@@ -1,10 +1,11 @@
 using System;
+using System.Collections;
 using System.Collections.Generic;
 using System.Text;
 
 namespace CalculatorApp
 {
-    public class CalculatorList<TType>
+    public class CalculatorList<TType> : IEnumerable<TType>, IEnumerable
     {
         List<TType> m_vector;
 
@@ -128,5 +129,13 @@ namespace CalculatorApp
             suffix = " =";
             return true;
         }
-    }
+
+		/// <inheritdoc />
+		public IEnumerator<TType> GetEnumerator()
+			=> m_vector.GetEnumerator();
+
+		/// <inheritdoc />
+		IEnumerator IEnumerable.GetEnumerator()
+			=> GetEnumerator();
+	}
 }

src/Calculator.Shared/Common/NavCategory.cs

@@ -561,7 +561,7 @@ namespace CalculatorApp
                         string categoryName = resProvider.GetResourceString(nameResourceKey + "Text");
                         string categoryAutomationName = LocalizationStringUtil.GetLocalizedString(navCategoryItemAutomationNameFormat, categoryName, m_Name);
 
-                        m_Categories.Append( new NavCategory(
+                        m_Categories.Add( new NavCategory(
                             categoryName,
                             categoryAutomationName,
                             (categoryInitializer.Value.glyph),

src/Calculator.Shared/Views/MainPage.xaml

@@ -142,7 +142,7 @@
 												 DataContext="{x:Bind Model}"
 												 IsSettingsVisible="False"
 												 Loaded="OnNavLoaded"
-												 MenuItemsSource="{x:Bind CreateUIElementsForCategories(Model.Categories), Mode=OneWay}"
+												 MenuItemsSource="{x:Bind UIElementsForCategories, Mode=OneWay}"
 												 OpenPaneLength="{StaticResource SplitViewOpenPaneLength}"
 												 SelectionChanged="OnNavSelectionChanged"
 												 TabIndex="1"

src/Calculator.Shared/Views/MainPage.xaml.cs

@@ -427,9 +427,11 @@ namespace CalculatorApp
             }
         }
 
-        public List<object> CreateUIElementsForCategories(ObservableCollection<NavCategoryGroup> categories)
+		public CalculatorList<object> UIElementsForCategories => CreateUIElementsForCategories(Model.Categories);
+
+		public CalculatorList<object> CreateUIElementsForCategories(ObservableCollection<NavCategoryGroup> categories)
         {
-            var menuCategories = new List<object>();
+            var menuCategories = new CalculatorList<object>();
 
             foreach (var group in categories)
             {