Merge branch 'develop' into datagrid-rowheader-alignment

Author: chuuddo

docs/release-notes/1.4.0.md

@@ -123,3 +123,4 @@
 - [#2346](https://github.com/MahApps/MahApps.Metro/issues/2346) TabControl with VS style
 - [#2090](https://github.com/MahApps/MahApps.Metro/issues/2090) VS TabItem
 - [#1890](https://github.com/MahApps/MahApps.Metro/issues/1890) How do i use the CloseCommand in StandardTabControl with VS Style
+- [#2261](https://github.com/MahApps/MahApps.Metro/issues/2261) ComboBox context menu.

src/MahApps.Metro.Samples/MahApps.Metro.Demo/MahApps.Metro.Demo.Shared/ExampleViews/SelectionExamples.xaml

@@ -133,6 +133,11 @@
                           Controls:TextBoxHelper.ClearTextButton="True"
                           Controls:TextBoxHelper.Watermark="Please select an item..."
                           SelectedIndex="0">
+                    <ComboBox.ContextMenu>
+                        <ContextMenu>
+                            <MenuItem Header="Test" />
+                        </ContextMenu>
+                    </ComboBox.ContextMenu>
                     <ComboBoxItem Content="Item 1" />
                     <ComboBoxItem Content="Item 2" />
                     <ComboBoxItem Content="Very long Item 3 for MahApps.Metro" />
@@ -145,6 +150,10 @@
                           Controls:TextBoxHelper.UseFloatingWatermark="True"
                           IsEditable="True"
                           SelectedIndex="0">
+                    <ComboBox.ContextMenu>
+                        <ContextMenu IsEnabled="False"
+                                     Visibility="Collapsed" />
+                    </ComboBox.ContextMenu>
                     <ComboBoxItem Content="Item 1" />
                     <ComboBoxItem Content="Item 2" />
                     <ComboBoxItem Content="Very long Item 3 for MahApps.Metro" />

src/MahApps.Metro/MahApps.Metro/Styles/Controls.ComboBox.xaml

@@ -471,6 +471,14 @@
                         </VisualStateManager.VisualStateGroups>
                     </Grid>
                     <ControlTemplate.Triggers>
+                        <MultiDataTrigger>
+                            <MultiDataTrigger.Conditions>
+                                <Condition Binding="{Binding RelativeSource={RelativeSource Self}, Path=IsEditable}" Value="True" />
+                                <Condition Binding="{Binding RelativeSource={RelativeSource Self}, Path=ContextMenu, Converter={x:Static converters:IsNullConverter.Instance}}" Value="False" />
+                            </MultiDataTrigger.Conditions>
+                            <Setter TargetName="PART_EditableTextBox" Property="ContextMenu" Value="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=ContextMenu}" />
+                        </MultiDataTrigger>
+
                         <MultiDataTrigger>
                             <MultiDataTrigger.Conditions>
                                 <Condition Binding="{Binding RelativeSource={RelativeSource Self}, Path=IsEditable}" Value="False" />