ButtonSpinner: Fixed tabbing issues.

ExtendedWPFToolkitSolution/Src/WPFToolkit.Extended/Themes/Generic.xaml

@@ -914,6 +914,7 @@
 
     <Style TargetType="{x:Type local:ButtonSpinner}">
         <Setter Property="Focusable" Value="False" />
+        <Setter Property="IsTabStop" Value="True" />
         <Setter Property="HorizontalContentAlignment" Value="Center" />
         <Setter Property="BorderBrush">
             <Setter.Value>
@@ -940,8 +941,8 @@
                                         <RowDefinition Height="1" />
                                         <RowDefinition Height="*" />
                                     </Grid.RowDefinitions>
-                                    <RepeatButton x:Name="IncreaseButton" SnapsToDevicePixels="True" Grid.Row="0"  Style="{StaticResource SpinButtonStyle}" ContentTemplate="{StaticResource IncreaseGlyph}" ClickMode="Press" />
-                                    <RepeatButton x:Name="DecreaseButton" SnapsToDevicePixels="True" Grid.Row="2" Style="{StaticResource SpinButtonStyle}" ContentTemplate="{StaticResource DecreaseGlyph}" ClickMode="Press" />
+                                    <RepeatButton x:Name="IncreaseButton" SnapsToDevicePixels="True" Grid.Row="0"  Style="{StaticResource SpinButtonStyle}" ContentTemplate="{StaticResource IncreaseGlyph}" ClickMode="Press" IsTabStop="{Binding IsTabStop, RelativeSource={RelativeSource TemplatedParent}}" />
+                                    <RepeatButton x:Name="DecreaseButton" SnapsToDevicePixels="True" Grid.Row="2" Style="{StaticResource SpinButtonStyle}" ContentTemplate="{StaticResource DecreaseGlyph}" ClickMode="Press" IsTabStop="{Binding IsTabStop, RelativeSource={RelativeSource TemplatedParent}}" />
                                 </Grid>
                                 <ContentControl x:Name="presentationSite" Focusable="False"
                                                 HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}"
@@ -991,7 +992,7 @@
         <Setter Property="Template">
             <Setter.Value>
                 <ControlTemplate TargetType="{x:Type local:DateTimeUpDown}">
-                    <local:ButtonSpinner x:Name="Spinner">
+                    <local:ButtonSpinner x:Name="Spinner" IsTabStop="False">
                         <TextBox x:Name="TextBox" BorderThickness="0" 
                                  FontFamily="{TemplateBinding FontFamily}" 
                                  FontSize="{TemplateBinding FontSize}"