Show ContextMenu on Left Click using only XAML.

Question

The default behavior of a WPF ContextMenu is to display it when the user right-clicks. I want the ContextMenu to show when the user left-clicks. It seems like this should be a simple property on ContextMenu, but it is not.

I rigged it, so that I handle the LeftMouseButtonDown event in the code-behind and then display the context menu.

I'm using MVVM in my project which means I'm using data templates for the items that have the context menus. It would be much more elegant to get rid of the code-behind and find a way to display the context menu using triggers or properties in the XAML.

Any ideas or solutions to this issue?

Answer 1

Unfortunately I don't think there is a XAML only solution to this one. The context-menu behavior is baked in to the FrameworkElement.

Answer 2

What I would suggest doing is making a new static class with attached DependencyProperty. Call the class LeftClickContextMenu and the property Enabled (just ideas). When your registering the DependencyProperty add an on changed callback. Then in the property changed callback if Enabled is set to true then add a handler to the LeftMouseButtonDown event and do your stuff there. If Enabled is set to false remove the handler. This sould allow you to set it like a property on anything by simply using the following in your xaml.

<Border namespace:LeftClickContextMenu.Enabled="True" />

This technique is called an attached behavior and you can read more about it in this code project article: http://www.codeproject.com/KB/WPF/AttachedBehaviors.aspx