wait callback functions in Expyriment (0.7)

wait_callback.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-
"""
Demonstration of wait callback functions in Expyriment
"""

from expyriment import control, design, misc, io, stimuli

control.defaults.quit_key = None # switch off quitting key

# my wait callback function
def check_keyboard():
    global feedback_value
    key = io.Keyboard().check()
    if key == misc.constants.K_ESCAPE:
        stimuli.TextScreen("Feedback {0}".format(feedback_value),
        "Quitting Experiment? (y/n)").present()
        key, rt = io.Keyboard().wait_char(["y", "n"], check_for_control_keys=False)
        print key
        if key == "y":
            control.end()
            exit()


exp = control.initialize()
control.start(exp)

feedback_value = 0
while True: # wait forever
    feedback_value += 1
    stimuli.TextScreen("Demo quit wait", "press ESC to quit").present()
    exp.clock.wait(10000, function=check_keyboard)

control.end()