我不确定我是否理解您的问题，但代码的问题在于您每次更新播放器时都会创建一个球。只需删除 player update 方法中的最后四行并取消注释 ball 的 update 方法中的行，一切正常。
其他提示
当球离开屏幕时删除它们。这将防止游戏运行缓慢或崩溃。可以通过在球更新方法中添加if self.rect.bottom < 0: self.kill()来实现。
在适当的时候使用elif。
在播放器更新方法中，您定义了一个属性self.speedx，该属性仅在该方法内部使用，因此最好只使用局部变量。此外，不鼓励在 __init__ 方法之外定义属性。
您的代码稍作修改。
import pygame
pygame.init()
is_running = True # Use lowercase_and_underscore for variable names.
WIDTH = 800
HEIGHT = 600
FPS = 60
clock = pygame.time.Clock()
window = pygame.display.set_mode((WIDTH, HEIGHT))
class Player(pygame.sprite.Sprite):
def __init__(self):
pygame.sprite.Sprite.__init__(self)
self.image = pygame.Surface((60, 30))
self.image.fill((200, 255, 200))
self.rect = self.image.get_rect()
self.rect.centerx = WIDTH / 2
self.rect.bottom = HEIGHT - 30
def update(self):
speedx = 0 # Don't define attributes outside __init__. Local variable works in this case instead.
keystate = pygame.key.get_pressed()
if keystate[pygame.K_a]:
speedx = -5
elif keystate[pygame.K_d]: # Use elif so it doesn't need to check this condition if the above is true.
speedx = 5
self.rect.x += speedx
if self.rect.right + speedx > WIDTH:
self.rect.right = WIDTH
elif self.rect.left + speedx < 0: # Use elif so it doesn't need to check this condition if the above is true.
self.rect.left = 0
def shoot(self):
ball = Ball(self.rect.centerx, self.rect.top)
all_sprites.add(ball)
balls.add(ball)
class Ball(pygame.sprite.Sprite):
def __init__(self, x, y):
pygame.sprite.Sprite.__init__(self)
self.image = pygame.Surface((10, 10))
self.image.fill((100, 150, 200))
self.rect = self.image.get_rect()
self.rect.bottom = y
self.rect.centerx = x
self.speedy = -3
def update(self):
if self.rect.bottom < 0: # Chack if the ball has exit above the screen.
self.kill() # If it has it should delete itself.
self.rect.y += self.speedy
all_sprites = pygame.sprite.Group()
balls = pygame.sprite.Group()
player = Player()
all_sprites.add(player)
while is_running:
clock.tick(FPS)
print(all_sprites)
for event in pygame.event.get():
if event.type == pygame.QUIT:
is_running = False
elif event.type == pygame.KEYDOWN:
if event.key == pygame.K_SPACE:
player.shoot()
window.fill((0, 0, 30))
all_sprites.update()
all_sprites.draw(window)
pygame.display.flip()
pygame.quit()
quit()
编辑：将球保持在桨上并利用空间发射
首先，您可以在 Player 类中创建一个属性 self.current_ball，它将引用球拍上的球。然后在 Player 类的 update 方法中更新球相对于球拍的位置。
要让球保持在桨上，你必须将球的self.speedy 更改为从 0 开始，否则它会在创建后直接移动。当您调用 player.shoot() 方法时，您将设置 self.speedy = -3 将开始球移动。
启动后，您只需在桨上创建一个新球并重复相同的过程。
import pygame
pygame.init()
is_running = True # Use lowercase_and_underscore for variable names.
WIDTH = 800
HEIGHT = 600
FPS = 60
clock = pygame.time.Clock()
window = pygame.display.set_mode((WIDTH, HEIGHT))
class Player(pygame.sprite.Sprite):
def __init__(self):
pygame.sprite.Sprite.__init__(self)
self.image = pygame.Surface((60, 30))
self.image.fill((200, 255, 200))
self.rect = self.image.get_rect()
self.rect.centerx = WIDTH / 2
self.rect.bottom = HEIGHT - 30
self.current_ball = Ball(self.rect.centerx, self.rect.top)
all_sprites.add(self.current_ball)
balls.add(self.current_ball)
def update(self):
speedx = 0 # Don't define attributes outside __init__. Local variable works in this case instead.
keystate = pygame.key.get_pressed()
if keystate[pygame.K_a]:
speedx = -5
elif keystate[pygame.K_d]: # Use elif so it doesn't need to check this condition if the above is true.
speedx = 5
self.rect.x += speedx
if self.rect.right + speedx > WIDTH:
self.rect.right = WIDTH
elif self.rect.left + speedx < 0: # Use elif so it doesn't need to check this condition if the above is true.
self.rect.left = 0
self.current_ball.rect.midbottom = self.rect.midtop # Set the ball position relative to paddle position.
def shoot(self):
self.current_ball.speedy = -3 # The ball should start moving.
self.current_ball = Ball(self.rect.centerx, self.rect.top) # Create a new ball on the paddle.
all_sprites.add(self.current_ball)
balls.add(self.current_ball)
class Ball(pygame.sprite.Sprite):
def __init__(self, x, y):
pygame.sprite.Sprite.__init__(self)
self.image = pygame.Surface((10, 10))
self.image.fill((100, 150, 200))
self.rect = self.image.get_rect()
self.rect.bottom = y
self.rect.centerx = x
self.speedy = 0 # The ball don't move from the beginning.
def update(self):
if self.rect.bottom < 0: # Chack if the ball has exit above the screen.
self.kill() # If it has it should delete itself.
self.rect.y += self.speedy
all_sprites = pygame.sprite.Group()
balls = pygame.sprite.Group()
player = Player()
all_sprites.add(player)
while is_running:
clock.tick(FPS)
print(all_sprites)
for event in pygame.event.get():
if event.type == pygame.QUIT:
is_running = False
elif event.type == pygame.KEYDOWN:
if event.key == pygame.K_SPACE:
player.shoot()
window.fill((0, 0, 30))
all_sprites.update()
all_sprites.draw(window)
pygame.display.flip()
pygame.quit()
quit()