set_input_focus/3
set_input_focus(+WindowSpec, +RevertTo, +Time)
Changes the input focus and the last-focus-change
time. It has no effect if the specified Time is earlier than the
current last-focus-change-time or later than the current X server
time. It generates focus_in
and focus_out
events.
WindowSpec is one of:
pointer_root
none
RevertTo specifies which window that the input focus should revert to, if the current focus becomes not viewable. One of:
parent
pointer_root
none
Time is a timestamp in milliseconds (from an event) or
current_time
.