在ListView的ItemTemplate中使用的AvalonEdit中的挂钩命令不起作用

I have used AvalonEdit control in my project. When I use shortcut keys like Ctrl+C or Ctrl+V, associated copy/paste commands works fine. I decided to use these commands in context menu for more usability because some users get used to right-click instead of shortcut. I used the following XAML code for control:I have used AvalonEdit control in my project. W