Inheriting CardViewer from wxPanel was causing problems with the focus

src/gui/control/card_viewer.cpp

@@ -20,7 +20,7 @@ DEFINE_EVENT_TYPE(EVENT_SIZE_CHANGE);
 // ----------------------------------------------------------------------------- : CardViewer
 
 CardViewer::CardViewer(Window* parent, int id, long style)
-	: wxPanel(parent, id, wxDefaultPosition, wxDefaultSize, style & wxNO_BORDER ? style : style | wxSUNKEN_BORDER)
+	: wxControl(parent, id, wxDefaultPosition, wxDefaultSize, style)
 	, up_to_date(false)
 {}
 

src/gui/control/card_viewer.hpp

@@ -22,7 +22,7 @@ DECLARE_EVENT_TYPE(EVENT_SIZE_CHANGE, <not used>)
 // ----------------------------------------------------------------------------- : CardViewer
 
 /// A control to view a single card
-class CardViewer : public wxPanel, public DataViewer {
+class CardViewer : public wxControl, public DataViewer {
   public:
 	CardViewer(Window* parent, int id, long style = 0);