Switched to using a routed command for the copy rather than an event handler.

Author: Keboo

MainDemo.Wpf/App.xaml

@@ -66,21 +66,22 @@
                                             </materialDesign:PackIcon.Style>
                                         </materialDesign:PackIcon>
                                     </materialDesign:PopupBox.ToggleContent>
-                                    <StackPanel>
-                                        <Border MaxHeight="600" MaxWidth="800">
+                                    <Border MaxHeight="600" MaxWidth="800">
+                                        <StackPanel>
                                             <avalonEdit:TextEditor Document="{Binding Xaml, RelativeSource={RelativeSource TemplatedParent}, Converter={StaticResource TextDocumentValueConverter}}" 
-                                                               Style="{StaticResource AvalonTextEditorXamlDisplay}" />
-                                        </Border>
-                                        <Button
-                                            Margin="0 10 0 0"
-                                            Tag="{Binding Xaml, RelativeSource={RelativeSource TemplatedParent}}"
-                                            Click="CopyButton_onClick"
-                                            HorizontalAlignment="Right"
-                                            Style="{StaticResource MaterialDesignRaisedButton}"
-                                            >
-                                            COPY
-                                        </Button>
-                                    </StackPanel>
+                                                                   Style="{StaticResource AvalonTextEditorXamlDisplay}" />
+                                            <Button
+                                                Margin="0 10 0 0"
+                                                Tag="{Binding Xaml, RelativeSource={RelativeSource TemplatedParent}}"
+                                                HorizontalAlignment="Right"
+                                                Command="Copy"
+                                                CommandParameter="{Binding Xaml, RelativeSource={RelativeSource TemplatedParent}}"
+                                                Content="_COPY"
+                                                Style="{StaticResource MaterialDesignRaisedButton}">
+                                            </Button>
+                                        </StackPanel>
+                                    </Border>
+
                                 </materialDesign:PopupBox>
                                 <Grid>
                                     <AdornerDecorator>

MainDemo.Wpf/App.xaml.cs

@@ -1,15 +1,5 @@
-using System;
-using System.Collections.Generic;
-using System.Configuration;
-using System.Data;
-using System.Globalization;
-using System.Linq;
-using System.Threading;
-using System.Threading.Tasks;
+using ShowMeTheXAML;
 using System.Windows;
-using System.Windows.Controls;
-using System.Windows.Markup;
-using ShowMeTheXAML;
 
 namespace MaterialDesignColors.WpfExample
 {
@@ -31,10 +21,5 @@ protected override void OnStartup(StartupEventArgs e)
 
             base.OnStartup(e);
         }
-
-        private void CopyButton_onClick(object sender, RoutedEventArgs e) {
-            var toBeCopied = ((Button)sender).Tag.ToString();
-            Clipboard.SetDataObject(toBeCopied);
-        }
     }
 }

MainDemo.Wpf/MainWindow.xaml

@@ -13,6 +13,9 @@
         TextOptions.TextRenderingMode="Auto"
         Background="{DynamicResource MaterialDesignPaper}"
         FontFamily="{StaticResource MaterialDesignFont}" Icon="favicon.ico">
+    <Window.CommandBindings>
+        <CommandBinding Command="Copy" Executed="OnCopy"></CommandBinding>
+    </Window.CommandBindings>
     <Window.Resources>
         <ResourceDictionary>
             <ResourceDictionary.MergedDictionaries>

MainDemo.Wpf/MainWindow.xaml.cs

@@ -1,4 +1,6 @@
-using MaterialDesignColors.WpfExample.Domain;
+using System;
+using System.Diagnostics;
+using MaterialDesignColors.WpfExample.Domain;
 using MaterialDesignThemes.Wpf;
 using System.Threading;
 using System.Threading.Tasks;
@@ -55,5 +57,20 @@ private async void MenuPopupButton_OnClick(object sender, RoutedEventArgs e)
 
             await DialogHost.Show(sampleMessageDialog, "RootDialog");            
         }
+
+        private void OnCopy(object sender, ExecutedRoutedEventArgs e)
+        {
+            if (e.Parameter is string stringValue)
+            {
+                try
+                {
+                    Clipboard.SetText(stringValue, TextDataFormat.UnicodeText);
+                }
+                catch (Exception ex)
+                {
+                    Trace.WriteLine(ex.ToString());
+                }
+            }
+        }
     } 
 }