python pygame pause function

问题

I am beginner and have a problem with my code. Here you can see a short excerpt of my code.

It's a simple snake game I created but I was trying to add a pause. I got it but when I start the pause I am not able to close it.

Possibly there is a basic mistake in my code so I couldn't advance. I hope you can help me.

Thank you in advance!

def checkquit(e):
    running = True
    pause = False
    for ev in e:
        if ev.type == pygame.QUIT:
            exit(0)
            running = True

        if ev.type == pygame.KEYDOWN and ev.key == pygame.K_ESCAPE:
            quit(0)
            running = True

        if ev.type == pygame.KEYDOWN and ev.key == pygame.K_p:
            pause = False

    while pause:
        #running = False
        pause = True   
        red = (255,0,0)

        screen = pygame.display.set_mode((800,500))
        screen.fill((0,0,0))

        my_font = pygame.font.SysFont("monospace", 50)
        my_font_two = pygame.font.SysFont("monospace", 10)

        text1 = myfont.render("Pause!", 100, red)
        text2 = myfont.render("Please restart the game", 100, red)

        screen.blit(text2, (10, 200))
        screen.blit(text1, (230, 100))

        pygame.display.update()

        for ev in e:
            if ev.type == pygame.QUIT:
                pause = False
            if ev.type == pygame.KEYDOWN and ev.key == pygame.K_ESCAPE:
                pause = False      
            if ev.type == pygame.KEYDOWN and ev.key == pygame.K_p:
                pause = True

回答1:

The pause screen is displayed in a separate application loop. You've to get the events in that loop, too. Note, in your code, the content of e never changes in the "pause" loop:

def checkquit(e):
    global running
    running = True
    pause = False
    for ev in e:
        if ev.type == pygame.QUIT:
            exit(0)
            running = True
        if ev.type == pygame.KEYDOWN and ev.key == pygame.K_ESCAPE:
            quit(0)
            running = True
        if ev.type == pygame.KEYDOWN and ev.key == pygame.K_p:
            pause = True

    while pause:

        # [...]


        # get the new events
        e = pygame.event.get()

        # handle the events in the loop
        for ev in e:
            if ev.type == pygame.QUIT:
                pause = False
            if ev.type == pygame.KEYDOWN and ev.key == pygame.K_ESCAPE:
                pause = False      
            if ev.type == pygame.KEYDOWN and ev.key == pygame.K_p:
                pause = True

runnung seems to be a variable in global namespace. You've to use the global statement to change its state. Furthermore it is superfluous to recreate the window surface in the "pause" loop.

screen = pygame.display.set_mode((800,500))

---

I recommend to change the game process. Use 1 application loop. e.g.:

myfont=pygame.font.SysFont("monospace",50)
myfonttwo=pygame.font.SysFont("monospace",10)
text1=myfont.render("Pause!",100,red)
text2=myfont.render("Please restart the game",100,red)

def checkquit(e):
    global running, pause
    for ev in e:
        if ev.type == pygame.QUIT:
            exit(0)
            running = True
        if ev.type == pygame.KEYDOWN and ev.key == pygame.K_ESCAPE:
            if pause:
                pause = False
            else:
                quit(0)
                running = True
        if ev.type == pygame.KEYDOWN and ev.key == pygame.K_p:
            pause = not pause

running, pause = True, False
while running:
    events = pygame.event.get()
    checkquit(events)

    screen.fill((0,0,0))
    if pause:
        # draw pause screen
        screen.blit(text2,(10,200))
        screen.blit(text1,(230,100))

    else:
        # draw game
        # [...]

    pygame.display.update() 

回答2:

I editet my code to this one:

def checkquit(e): running = True pause = False for ev in e: if ev.type == pygame.QUIT: exit(0) running = False pause = False

    if ev.type == pygame.KEYDOWN and ev.key == pygame.K_ESCAPE:
        quit(0)
        running = False
        pause = False

    if ev.type == pygame.KEYDOWN and ev.key == pygame.K_p:
            pause = True
            running = False



while pause: 
    pause = True
    red = (255,0,0)
    screen = pygame.display.set_mode((800,800))
    screen.fill((0,0,0))
    myfont=pygame.font.SysFont("monospace",50)
    myfonttwo=pygame.font.SysFont("monospace",10)
    myfonttwo=pygame.font.SysFont("monospace",10)
    text1=myfont.render("Pause!",100,red)
    text2=myfont.render("Please resume your game!",100,red)
    text3=myfont.render("Game starts in 10 seconds!",100,red)
    screen.blit(text2,(50,200))
    screen.blit(text1,(300,100))
    screen.blit(text3,(0,300))

    pygame.display.update()
    pygame.time.delay(4500)
    if ev.type == pygame.KEYDOWN and ev.key == pygame.K_p:
        pause = False

And it works very good! Thanks for your advices!

来源：https://stackoverflow.com/questions/59121322/python-pygame-pause-function