A child focus event is sent to a (parent-)window when one of its child windows gains focus,
so that the window could restore the focus back to its corresponding child
if it loses it now and regains later.
Notice that child window is the direct child of the window receiving event.
to retreive the window which is actually getting focus.
Event table macros
To process a child focus event, use this event handler macro to direct input to a member
function that takes a wxChildFocusEvent argument.
Process a wxEVT_CHILD_FOCUS event.
(wxWindow * win = NULL
The direct child which is (or which contains the window which is) receiving the focus.
Returns the direct child which receives the focus, or a (grand-)parent of the control receiving the focus.