Have you tried to handle the wxEVT_LEFT_DOWN and wxEVT_LEFT_UP events for your text control? Either by adding them to the static message map, or by calling Connect () for the handler methods.
Edit:
Not all events are listed in the class documentation. You also need to go up in the hierarchy, from wxTextCtrl to wxControl to wxWindow. Unfortunately, I cannot find documentation for mouse events in any class. Their processing should be allowed, even if it is not documented.
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