Source code for pypdevs.realtime.threadingTkInter
# Copyright 2014 Modelling, Simulation and Design Lab (MSDL) at
# McGill University and the University of Antwerp (http://msdl.cs.mcgill.ca/)
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
def tkMainThreadPoller(tk, queue):
"""
The polling function to register with Tk at the start. This will do the actual scheduling in Tk.
:param tk: the Tk instance to use
:param queue: the queue to check
"""
global tkRunningID
while 1:
try:
time, func = queue.popleft()
tkRunningID = tk.after(time, func)
except TypeError:
# Was an invalidation call
try:
if tkRunningID is not None:
tk.after_cancel(tkRunningID)
except IndexError:
# Nothing to cancel
pass
tkRunningID = None
except IndexError:
break
tk.after(10, tkMainThreadPoller, tk, queue)
[docs]class ThreadingTkInter(object):
"""
Tk Inter subsystem for realtime simulation
"""
[docs] def __init__(self, tk):
"""
Constructor
:param queue: the queue object that is also used by the main thread to put events on the main Tk object
"""
self.runningID = None
self.last_infinity = False
import collections
queue = collections.deque()
self.queue = queue
tk.after(10, tkMainThreadPoller, tk, queue)
[docs] def unlock(self):
"""
Unlock the waiting thread
"""
# Don't get it normally, as it would seem like a method call
getattr(self, "func")()
[docs] def wait(self, t, func):
"""
Wait for the specified time, or faster if interrupted
:param t: time to wait
:param func: the function to call
"""
if t == float('inf'):
self.last_infinity = True
else:
self.last_infinity = False
self.func = func
self.queue.append((int(t*1000), self.unlock))
[docs] def interrupt(self):
"""
Interrupt the waiting thread
"""
if not self.last_infinity:
self.queue.append(None)
self.unlock()