我有以下代码:
import threading
import time
class TestWorker (threading.Thread):
def __init__(self, threadID, name):
threading.Thread.__init__(self)
self.threadID = threadID
self.name = name
def run(self):
print "Starting " + self.name
time.sleep(20)
print "Exiting " + self.name
# how do I let the calling thread know it's done?
class TestMain:
def __init__(self):
pass
def do_work(self):
thread = TestWorker(1, "Thread-1")
thread.start()
def do_something_else(self):
print "Something else"
def on_work_done(self):
print "work done"
如何让主线程知道 TestWorker
已经完成(调用 on_work_done()
),而不阻塞对 do_something_else()
的调用> 像 thread.join()
那样?
最佳答案
您可以为您的线程实例提供一个可选的回调函数,以便在它完成时调用。
请注意,我添加了一个 Lock
来防止并发打印(这会阻塞)。
print_lock = threading.Lock() # Prevent threads from printing at same time.
class TestWorker(threading.Thread):
def __init__(self, threadID, name, callback=lambda: None):
threading.Thread.__init__(self)
self.threadID = threadID
self.name = name
self.callback = callback
def run(self):
with print_lock:
print("Starting " + self.name)
time.sleep(3)
with print_lock:
print("Exiting " + self.name)
self.callback()
class TestMain:
def __init__(self):
self.work_done = False
def do_work(self):
thread = TestWorker(1, "Thread-1", self.on_work_done)
thread.start()
def do_something_else(self):
with print_lock:
print("Something else")
def on_work_done(self):
with print_lock:
print("work done")
self.work_done = True
main = TestMain()
main.do_work()
while not main.work_done:
main.do_something_else()
time.sleep(.5) # do other stuff...
print('Done')
输出:
Starting Thread-1
Something else
Something else
Something else
Something else
Something else
Something else
Exiting Thread-1
work done
Done
关于python - 确定线程是否完成的非阻塞方式?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/38977472/