diff --git a/samples/ControlCatalog/Pages/ViewboxPage.xaml b/samples/ControlCatalog/Pages/ViewboxPage.xaml
index a31a52d2383..e66655253ce 100644
--- a/samples/ControlCatalog/Pages/ViewboxPage.xaml
+++ b/samples/ControlCatalog/Pages/ViewboxPage.xaml
@@ -27,20 +27,24 @@
             <Slider Minimum="10" Maximum="200" Value="100" x:Name="HeightSlider" TickFrequency="25" TickPlacement="TopLeft" />
             <TextBlock Text="Stretch" />
             <ComboBox x:Name="StretchSelector" HorizontalAlignment="Stretch" SelectedIndex="0" Margin="0,0,0,2">
-              <collections:ArrayList>
-                <Stretch>Uniform</Stretch>
-                <Stretch>UniformToFill</Stretch>
-                <Stretch>Fill</Stretch>
-                <Stretch>None</Stretch>
-              </collections:ArrayList>
+              <ComboBox.ItemsSource>
+                <collections:ArrayList>
+                  <Stretch>Uniform</Stretch>
+                  <Stretch>UniformToFill</Stretch>
+                  <Stretch>Fill</Stretch>
+                  <Stretch>None</Stretch>
+                </collections:ArrayList>
+              </ComboBox.ItemsSource>
             </ComboBox>
             <TextBlock Text="Stretch Direction" />
             <ComboBox x:Name="StretchDirectionSelector" SelectedIndex="0" HorizontalAlignment="Stretch">
-              <collections:ArrayList>
-                <StretchDirection>Both</StretchDirection>
-                <StretchDirection>DownOnly</StretchDirection>
-                <StretchDirection>UpOnly</StretchDirection>
-              </collections:ArrayList>
+              <ComboBox.ItemsSource>
+                <collections:ArrayList>
+                  <StretchDirection>Both</StretchDirection>
+                  <StretchDirection>DownOnly</StretchDirection>
+                  <StretchDirection>UpOnly</StretchDirection>
+                </collections:ArrayList>
+              </ComboBox.ItemsSource>
             </ComboBox>
           </StackPanel>
         </Grid>