下面介绍以threading模块来实现定时器的方法。
首先介绍一个最简单实现：
import threading
def say_sth(str):
print str
t = threading.timer(2.0, say_sth,[str])
t.start()
if __name__ == ‘__main__’:
timer = threading.timer(2.0,say_sth,[‘i am here too.’])
timer.start()
不清楚在某些特殊应用场景下有什么缺陷否。
下面是所要介绍的定时器类的实现：
class timer(threading.thread):
“””
very simple but useless timer.
“””
def __init__(self, seconds):
self.runtime = seconds
threading.thread.__init__(self)
def run(self):
time.sleep(self.runtime)
print “buzzzz!! time’s up!”
class countdowntimer(timer):
“””
a timer that can counts down the seconds.
“””
def run(self):
counter = self.runtime
for sec in range(self.runtime):
print counter
time.sleep(1.0)
counter -= 1
print “done”
class countdownexec(countdowntimer):
“””
a timer that execute an action at the end of the timer run.
“””
def __init__(self, seconds, action, args=[]):
self.args = args
self.action = action
countdowntimer.__init__(self, seconds)
def run(self):
countdowntimer.run(self)
self.action(self.args)
def myaction(args=[]):
print “performing my action with args:”
print args
if __name__ == “__main__”:
t = countdownexec(3, myaction, [“hello”, “world”])
t.start()