屏幕填充似乎不起作用

Question

我已经编写了一个游戏，一切正常，所以现在我想要在游戏开始之前有一个屏幕。然后，您必须单击开始以继续游戏。到目前为止，我有以下代码：

if menu == 'start':
screen.fill((0,255,0))
txt = font.render('Start',True,(255,255,0))
txt_x = 480
txt_y = 290
buttonrect = pygame.Rect((txt_x,txt_y),txt.get_size())
pygame.draw.rect(screen,(0,0,255),buttonrect)
screen.blit(txt,(txt_x,txt_y))
if pygame.mouse.get_pressed()[0] and buttonrect.collidepoint(pygame.mouse.get_pos()):
menu = 'game'

我已将菜单设置为"开始"，但它不起作用。屏幕为黑色而不是绿色。但是当我点击坐标时，我就会进入游戏。我的代码有什么问题？

Answer 1

设置屏幕背景后需要更新主显示：

if menu == 'start':
screen.fill((0,255,0))
txt = font.render('Start',True,(255,255,0))
txt_x = 480
txt_y = 290
buttonrect = pygame.Rect((txt_x,txt_y),txt.get_size())
pygame.draw.rect(screen,(0,0,255),buttonrect)
screen.blit(txt,(txt_x,txt_y))
pygame.display.update()
if pygame.mouse.get_pressed()[0] and buttonrect.collidepoint(pygame.mouse.get_pos()):
menu = 'game'