ContextMenu now follows placement target font. (#2426)

Author: Keboo

MaterialDesignThemes.UITests/WPF/TextBoxes/TextBoxTests.cs

@@ -1,5 +1,6 @@
 using System;
 using System.ComponentModel;
+using System.Linq;
 using System.Threading.Tasks;
 using System.Windows;
 using System.Windows.Controls;
@@ -305,5 +306,47 @@ public async Task FloatingOffset_ValuesGetApproprietlyApplied()
 
             recorder.Success();
         }
+
+        [Fact]
+        [Description("Issue 2390")]
+        public async Task ContextMenu_FollowsTextBoxFontFamily()
+        {
+            await using var recorder = new TestRecorder(App);
+
+            var textBox = await LoadXaml<TextBox>(@"<TextBox FontFamily=""Times New Roman""/>");
+
+            await textBox.RightClick();
+
+            var contextMenu = await textBox.GetElement<ContextMenu>(".ContextMenu");
+
+            var textBoxFont = await textBox.GetFontFamily();
+            Assert.Equal("Times New Roman", textBoxFont?.FamilyNames.Values.First());
+            Assert.Equal(textBoxFont, await contextMenu.GetFontFamily());
+
+            recorder.Success();
+        }
+
+        [Fact]
+        [Description("Issue 2390")]
+        public async Task ContextMenu_UsesInheritedFontFamily()
+        {
+            await using var recorder = new TestRecorder(App);
+
+            var stackPanel = await LoadXaml<StackPanel>(@"
+<StackPanel TextElement.FontFamily=""Times New Roman"">
+    <TextBox />
+</StackPanel>
+");
+            var textBox = await stackPanel.GetElement<TextBox>("/TextBox");
+            await textBox.RightClick();
+
+            var contextMenu = await textBox.GetElement<ContextMenu>(".ContextMenu");
+
+            var textBoxFont = await textBox.GetFontFamily();
+            Assert.Equal("Times New Roman", textBoxFont?.FamilyNames.Values.First());
+            Assert.Equal(textBoxFont, await contextMenu.GetFontFamily());
+
+            recorder.Success();
+        }
     }
 }

MaterialDesignThemes.Wpf/Themes/MaterialDesignTheme.Menu.xaml

@@ -9,7 +9,8 @@
     <converters:TextFieldHintVisibilityConverter x:Key="StringIsEmptyVisibilityConverter" IsEmptyValue="Collapsed" IsNotEmptyValue="Visible"/>
     <converters:BrushRoundConverter x:Key="BrushRoundConverter"/>
 
-    <ContextMenu x:Key="MaterialDesignDefaultContextMenu">
+    <ContextMenu x:Key="MaterialDesignDefaultContextMenu"
+                 FontFamily="{Binding PlacementTarget.FontFamily, RelativeSource={RelativeSource Self}}">
         <MenuItem Command="Cut">
             <MenuItem.Icon>
                 <wpf:PackIcon Kind="ContentCut" />