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I have a context menu in WPF which will be driven by a List<String> to display a dynamically generated set of menu items.

The list is assigned to the ItemsSource property of the context menu, and correctly displays the content of the menu.

It I create a MenuItem in code behind, I can assign a click listener to the item, and then add that item to the Items list of the menu which correctly populates the list, and allows each item to call the click listener.

I have implemented this approach as shown below.

 private ContextMenu _elementContextMenu;

 public ContextMenu ElementContextMenu 
 get 
 if (_elementContextMenu == null) 
 _elementContextMenu = new ContextMenu();

 //root menu item
 _elementMenuRootItem = new MenuItem();
 _elementMenuRootItem.Click += _elementMenuRootItem_Click;
 _elementMenuRootItem.ItemsSource = ElementMenuContent;

 _elementContextMenu.Items.Add(_elementMenuRootItem);
 
 return _elementContextMenu;
 
 set _elementContextMenu = value; 
 

Using that approach, the click listener passes the clicked menu item as the source of the event, and I can cast it to a MenuItem as shown below:

 void _elementMenuRootItem_Click(object sender, RoutedEventArgs e) 
 MenuItem selectedMenuItem = (MenuItem)e.OriginalSource;
 

What I want to achieve is a list of items which show up as the root of the list.

If I bind the list of menu items (name ElementMenuContent in this implementation) to the ItemsSource property of the context menu, the menu is populated as I would like it to be, however there is no Click event in the ContextMenu.

The desired implementation is shown below:

 public ContextMenu ElementContextMenu 
 get 
 if (_elementContextMenu == null) 
 _elementContextMenu = new ContextMenu();
 _elementContextMenu.ItemsSource = ElementMenuContent;

 //Add a click listener directly to the ContextMenu object which allows
 //the source menu item which was clicked to be referenced in the same way 
 //as with a MenuItem click listener
 
 return _elementContextMenu;
 
 set _elementContextMenu = value; 
 

The component this is being implemented in extends the WPF Canvas, and is a .cs file only, so this must be implemented entirely in code. I cannot use XAML in this case.

Any help would be appreciated.

I'm not sure I understand this part of your question:

What I want to achieve is a list of items which show up as the root of the list.

As you said, there is no Click event available on the ContextMenu itself. The simplest solution would be to instead subscribe to PreviewMouseUp which will capture all mouse click activity and then you can use the MouseButtonEventArgs to access what you need.

PreviewMouseUp: https://docs.microsoft.com/en-us/dotnet/api/system.windows.uielement.previewmouseup?view=netframework-4.7.2

If this doesn't help, you can always look into creating a custom routed event: https://docs.microsoft.com/en-us/dotnet/framework/wpf/advanced/how-to-create-a-custom-routed-event

For anybody stuck on this same issue, the solution is to set the ItemsSource property of the menu itself (in this case, the ElementMenuContent object is a List<String>, and add an event handler to the ContextMenu which operates on the ClickEvent of any MenuItem component as follows:

 _elementContextMenu.ItemsSource = ElementMenuContent;

 _elementContextMenu.AddHandler(MenuItem.ClickEvent, new RoutedEventHandler(ElementContextMenuItemClick));

The handler method is defined as normal.

 public void ElementContextMenuItemClick(object sender, RoutedEventArgs e) 
 MenuItem selectedMenuItem = (MenuItem)e.OriginalSource;
 String command = selectedMenuItem.Header.ToString();
 SwimLaneController.Instance.ProcessContextMenuCommand(this, command);