我当前正在尝试编写一个实现以下功能的功能：
- 以随机顺序从列表"消息"中获取所有消息，同时确保没有重复。
- 在延迟在1-10秒之间延迟随机数秒后打印它们。
- 完成所有线程后，它将打印一个字符串"打印完成。您将在5秒内返回主菜单。"
但是，我遇到的问题是字符串"打印已经完成..."是在随机消息之间打印的，而不是在它们之后。
我的混乱源于以下事实：.join（）方法非常适合类似功能。仅在所有线程完成后才打印字符串。它们之间的主要区别在于，另一个函数不进行任何随机输入。取而代之的是，它在一个名为" messages_and_times"的全局字典上迭代，其中键：值对来自消息的用户输入和秒数（用户输入由另一个函数处理）。
）。下面您可以看到不起作用的函数option_3（），以及确实有效的函数option_2（）。在最底部，我将包括整个代码以供进一步参考。
有人可以帮助我理解我在做什么错吗？
预先感谢您的时间和帮助。
P.S。clear()功能在每个输入后都可以清除终端显示。
非工作功能：
def option_3():
clear()
messages = ["message_1", "message_2", "message_3", "message_4", "message_5",
"message_6", "message_7", "message_8", "message_9", "message_10"]
print("Printing initialized:n")
def threading_function(message, seconds):
time.sleep(seconds)
print(message)
for message in messages:
randomized_messages = []
random_index = random.randint(0, len(messages) - 1)
randomized_messages.append(messages.pop(random_index))
for msg in randomized_messages:
t = Thread(target=threading_function, args=(msg, random.choice(range(1,11))))
t.start()
t.join()
time.sleep(0.5)
print(
"nPrinting is finished. You will be returned to the main menu in 5 seconds.")
time.sleep(5)
main_menu()
工作功能：
def option_2():
global messages_and_times
clear()
print("Printing initialized:n")
def threading_function(message, seconds):
time.sleep(seconds)
print(message)
for message, seconds in messages_and_times.items():
t = Thread(target=threading_function, args=(message, seconds))
t.start()
t.join()
time.sleep(0.5)
print(
"nPrinting is finished. You will be returned to the main menu in 5 seconds.")
time.sleep(5)
main_menu()
整个main_menu（）函数：
import os
import random
clear = lambda: os.system('cls')
messages_and_times = {}
def main_menu():
def option_1():
global messages_and_times
clear()
message = input(
"Please type in a message you would like to add to the list:")
clear()
seconds = int(
input("Please type in the time of delay for this message:"))
messages_and_times[message] = seconds
def create_dictionary():
clear()
answer = input(
"Would you like to add another message? (yes/no)").lower()
if answer == "yes":
option_1()
elif answer == "no":
clear()
print("You will now be returned to the main menu.")
time.sleep(1.5)
main_menu()
else:
clear()
print("Please answer yes or no.")
time.sleep(1.5)
create_dictionary()
create_dictionary()
def option_2():
global messages_and_times
clear()
print("Printing initialized:n")
def threading_function(message, seconds):
time.sleep(seconds)
print(message)
for message, seconds in messages_and_times.items():
t = Thread(target=threading_function, args=(message, seconds))
t.start()
t.join()
time.sleep(0.5)
print(
"nPrinting is finished. You will be returned to the main menu in 5 seconds.")
time.sleep(5)
main_menu()
def option_3():
clear()
messages = ["message_1", "message_2", "message_3", "message_4", "message_5",
"message_6", "message_7", "message_8", "message_9", "message_10"]
randomized_messages = []
print("Printing initialized:n")
def threading_function(message, seconds):
time.sleep(seconds)
print(message)
for message in messages:
random_index = random.randint(0, len(messages) - 1)
randomized_messages.append(messages.pop(random_index))
for msg in randomized_messages:
t = Thread(target=threading_function, args=(msg, random.choice(range(1,11))))
t.start()
t.join()
time.sleep(0.5)
print(
"nPrinting is finished. You will be returned to the main menu in 5 seconds.")
time.sleep(5)
main_menu()
clear()
selection = 0
while selection == 0:
print(("-" * 15) + "MAIN MENU" + ("-" * 15) + "n")
print("1: Input a message and a corresponding time of delay before its display.")
print("2: Print your customized list of messages.")
print("3: Print random messages with random delays.n")
selection = int(input(
"Please select one of the options, by typing in the corresponding number:"))
if selection == 1:
option_1()
elif selection == 2:
option_2()
elif selection == 3:
option_3()
else:
clear()
print("Please select from options 1 - 3.n")
time.sleep(1.5)
main_menu()
编辑（最终解决方案以供将来参考）：
感谢Almog David的建议，这是我修改了我的功能以按预期工作的方式。我希望这有助于某人将来浏览解决方案。
option_2（）：
def option_2():
global messages_and_times
clear()
threads = []
print("Printing initialized:n")
def threading_function(message, seconds):
time.sleep(seconds)
print(message)
for message, seconds in messages_and_times.items():
t = Thread(target=threading_function, args=(message, seconds))
t.start()
threads.append(t)
for t in threads:
t.join()
time.sleep(0.5)
print(
"nPrinting is finished. You will be returned to the main menu in 5 seconds.")
time.sleep(5)
main_menu()
option_3（）：
def option_3():
clear()
messages = ["message_1", "message_2", "message_3", "message_4", "message_5",
"message_6", "message_7", "message_8", "message_9", "message_10"]
threads = []
print("Printing initialized:n")
def threading_function(message, seconds):
time.sleep(seconds)
print(message)
for message in messages:
t = Thread(target=threading_function, args=(
message, random.choice(range(1, 11))))
t.start()
threads.append(t)
for t in threads:
t.join()
time.sleep(0.5)
print(
"nPrinting is finished. You will be returned to the main menu in 5 seconds.")
time.sleep(5)
main_menu()
问题是您只等待最后一个线程加入（因为't'变量在循环结束时持有最后一个创建的线程对象），因此联接函数在最后一个时返回线程已完成，程序继续。
即使在选项2上，我也能够通过提供：
来复制此错误messages_and_times = {"message_0": 3,
"message_1": 3,
"message_2": 1}
上述配置的结果是：
message_2
Printing is finished. You will be returned to the main menu in 5 seconds.
message_0
message_1
您应该做的修复是：
threads = []
for message, seconds in messages_and_times.items():
t = Thread(target=threading_function, args=(message, seconds))
t.start()
threads.append(t)
for t in threads:
t.join()