feat: Update NumberBox example to reflect spin button placement in displayed XAML code

WinUIGallery/ContentIncludes.props

@@ -249,7 +249,6 @@
     <Content Include="ControlPagesSampleCode\NavigationView\NavigationViewSample6.txt" />
     <Content Include="ControlPagesSampleCode\NavigationView\NavigationViewSample8_xaml.txt" />
     <Content Include="ControlPagesSampleCode\NavigationView\NavigationViewSample9_xaml.txt" />
-    <Content Include="ControlPagesSampleCode\NumberBox\NumberBoxSample2_xaml.txt" />
     <Content Include="ControlPagesSampleCode\NumberBox\NumberBoxSample3_cs.txt" />
     <Content Include="ControlPagesSampleCode\NumberBox\NumberBoxSample3_xaml.txt" />
     <Content Include="ControlPagesSampleCode\System\FilePickerSample1_cs.txt" />

WinUIGallery/ControlPages/NumberBoxPage.xaml

@@ -29,9 +29,8 @@
                 </x:String>
             </local:ControlExample.Xaml>
         </local:ControlExample>
-
-        <local:ControlExample HeaderText="A NumberBox with a spin button." 
-                              XamlSource="NumberBox/NumberBoxSample2_xaml.txt">
+
+        <local:ControlExample HeaderText="A NumberBox with a spin button.">
             <local:ControlExample.Example>
                 <NumberBox x:Name="NumberBoxSpinButtonPlacementExample"
                               VerticalAlignment="Top"
@@ -44,13 +43,27 @@
                 </NumberBox>
             </local:ControlExample.Example>
             <local:ControlExample.Options>
-                <RadioButtons x:Name="SpinButtonPlacementGroup" Header="SpinButton placement">
-                    <RadioButton Content="Inline" Tag="Inline" Checked="RadioButton_Checked" />
-                    <RadioButton Content="Compact" Tag="Compact" Checked="RadioButton_Checked" IsChecked="True" />
+                <RadioButtons x:Name="SpinButtonPlacementGroup" Header="SpinButton placement" SelectedIndex="0" SelectionChanged="SpinButtonPlacementGroup_SelectionChanged">
+                    <x:String>Inline</x:String>
+                    <x:String>Compact</x:String>
                 </RadioButtons>
             </local:ControlExample.Options>
+            <local:ControlExample.Xaml>
+                <x:String xml:space="preserve">
+&lt;NumberBox
+    x:Name="NumberBoxSpinButtonPlacementExample"
+    Header="Enter an integer:" 
+    Value="1" 
+    SpinButtonPlacementMode="$(SpinButtonPlacementMode)"
+    SmallChange="10"
+    LargeChange="100" /&gt;
+                </x:String>
+            </local:ControlExample.Xaml>
+            <local:ControlExample.Substitutions>
+                <local:ControlExampleSubstitution Key="SpinButtonPlacementMode" Value="{x:Bind SpinButtonPlacementGroup.SelectedItem, Mode=OneWay}"/>
+            </local:ControlExample.Substitutions>
         </local:ControlExample>
-        
+
         <local:ControlExample HeaderText="A formatted NumberBox that rounds to the nearest 0.25." 
                               XamlSource="NumberBox/NumberBoxSample3_xaml.txt"
                               CSharpSource="NumberBox/NumberBoxSample3_cs.txt">

WinUIGallery/ControlPages/NumberBoxPage.xaml.cs

@@ -38,18 +38,16 @@ private void SetNumberBoxNumberFormatter()
             FormattedNumberBox.NumberFormatter = formatter;
         }
 
-        private void RadioButton_Checked(object sender, RoutedEventArgs e)
+        private void SpinButtonPlacementGroup_SelectionChanged(object sender, SelectionChangedEventArgs e)
         {
-            if (sender is RadioButton rb && NumberBoxSpinButtonPlacementExample != null)
+            if (sender is RadioButtons radioButtons)
             {
-                string spinButtonPlacementModeName = rb.Tag.ToString();
-
-                switch (spinButtonPlacementModeName)
+                switch (radioButtons.SelectedIndex)
                 {
-                    case "Inline":
+                    case 0:
                         NumberBoxSpinButtonPlacementExample.SpinButtonPlacementMode = NumberBoxSpinButtonPlacementMode.Inline;
                         break;
-                    case "Compact":
+                    case 1:
                         NumberBoxSpinButtonPlacementExample.SpinButtonPlacementMode = NumberBoxSpinButtonPlacementMode.Compact;
                         break;
                 }