键盘输入背景

Question

我一直在pygame工作，我想要一些键盘输入帮助。如果按下某个键，我会尝试放入，背景会变成红色。不幸的是，它不起作用。

也许是因为我没有打算或在语法上犯了错误？

import pygame 
pygame.init() 
white = (34,34,34) 
black=(0,0,0) 
red=(255,0,0) 
silver=(110,108,108) 
yellow=(193,206,104) 
yellow2=(213,230,100) 
gameDisplay = pygame.display.set_mode((800,600)) 
pygame.display.set_caption('Slither') 

gameExit=False 

lead_x = 300 
lead_y = 300 

while not gameExit: 
    for event in pygame.event.get(): 
     if event.type == pygame.QUIT: 
      gameExit = True 
     if event.type == pygame.KEYDOWN: 
      if event.key == pygame.K_LEFT: 
       lead_x -= 10 
       print("LEFT") 

      if event.key == pygame.K_RIGHT: 
       lead_x +=10 
       print("RIGHT") 
      if event.key == pygame.K_UP: 
       lead_y -=10 
       print("UP") 
      if event.key == pygame.K_DOWN: 
       lead_y +=10 
       print("DOWN") 
      if event.key == pygame.K_a: 
       gameDisplay.fill(red) 

    gameDisplay.fill(black) 
    pygame.draw.rect(gameDisplay, white,[lead_x,lead_y,30,100]) 
    pygame.draw.ellipse(gameDisplay, white,[-35+lead_x,-54+lead_y,75,100]) 
    pygame.draw.ellipse(gameDisplay, red,[-25+lead_x,-35+lead_y,20,34]) 
    pygame.draw.ellipse(gameDisplay, red,[10+lead_x,-35+lead_y,20,34]) 
    pygame.draw.rect(gameDisplay, silver,[470+lead_x,-35+lead_y,75,30]) 
    pygame.draw.ellipse(gameDisplay, yellow,[400+lead_x,-35+lead_y,75,30]) 


    pygame.display.update() 

pygame.quit() 
quit() 

Answer 1

你是填充红色的屏幕，但一旦for循环结束，你的显示更新之前画在它与黑色。在if之内不是直接调用fill，而是通过用新颜色更新background_color变量，并在事件循环完成后使用它作为填充颜色，使更改持久化。

#snip 
background_color = black 
while not gameExit: 
    for event in pygame.event.get(): 
     if event.type == pygame.QUIT: 
      gameExit = True 
     if event.type == pygame.KEYDOWN: 
      #snip 
      if event.key == pygame.K_a: 
       background_color = red 

    gameDisplay.fill(background_color) 
    pygame.draw.rect(gameDisplay, white,[lead_x,lead_y,30,100]) 
    #snip