cpython/Lib/lib-stdwin/WindowSched.py

59 lines
1.3 KiB
Python

# Combine a real-time scheduling queue and stdwin event handling.
# Uses the millisecond timer.
import stdwin, stdwinq
from stdwinevents import WE_TIMER
import mainloop
import sched
import time
# Delay function called by the scheduler when it has nothing to do.
# Return immediately when something is done, or when the delay is up.
#
def delayfunc(msecs):
#
# Check for immediate stdwin event
#
event = stdwinq.pollevent()
if event:
mainloop.dispatch(event)
return
#
# Use millisleep for very short delays or if there are no windows
#
if msecs < 100 or mainloop.countwindows() == 0:
if msecs > 0:
time.millisleep(msecs)
return
#
# Post a timer event on an arbitrary window and wait for it
#
window = mainloop.anywindow()
window.settimer(msecs/100)
event = stdwinq.getevent()
window.settimer(0)
if event[0] <> WE_TIMER:
mainloop.dispatch(event)
q = sched.scheduler().init(time.millitimer, delayfunc)
# Export functions enter, enterabs and cancel just like a scheduler
#
enter = q.enter
enterabs = q.enterabs
cancel = q.cancel
# Emptiness check must check both queues
#
def empty():
return q.empty() and mainloop.countwindows() == 0
# Run until there is nothing left to do
#
def run():
while not empty():
if q.empty():
mainloop.dispatch(stdwinq.getevent())
else:
q.run()