Determines whether a pane has the focus.
capi
pane-has-focus-p pane => focusp
| pane⇩ | 
A CAPI element. | 
| focusp | 
A boolean. | 
The generic function pane-has-focus-p is the predicate for whether pane currently has the input focus.
On Motif, pane-has-focus-p cannot be used in menu functions such as the enabled-function or popup-callback of a menu item. It will always return nil, because the focus is on the menu button when the user clicks on it.
accepts-focus-p
pane-descendant-child-with-focus
set-pane-focus
3.1.5 Focus
CAPI User Guide and Reference Manual (Windows version) - 01 Dec 2021 19:33:57