Question

I need to hook up an event that shows a WPF Popup control when a TextBox has focus and a keyboard shortcut is clicked. For instance. When typing in the TextBox field, the user can press ALT+H for help, to get a popup dialog showing input help. Pressing ALT+H “outside” the TextBox should not open the popup.

Any ideas?

Answer 1

Looks like a job for an Attached Event.

From MSDN:

The concept of
an attached event enables you to add a handler for a particular event
to an arbitrary element rather than to an element that actually
defines or inherits the event. In this case, neither the object
potentially raising the event nor the destination handling instance
defines or otherwise “owns” the event.

You can find details here, on the MSDN