python - 为什么这段代码没有绘制我想要的开始按钮？

Question

我已经尝试了很多，但仍然不明白为什么它不加载按钮。

import pygame
pygame.init()
screen = pygame.display.set_mode((3840,2160))
running = True
mouse = pygame.mouse.get_pos()

pygame.display.set_caption("GermanBall")
bg = pygame.image.load("Tan.jpg")
icon = pygame.image.load("box.png")
button1 = pygame.image.load("shirt.png").convert_alpha()
class Button():
    def __init__(self,x,y,image):
        self.image = image 
        self.rect = self.image.get_rect()
        self.rect.topleft = (x,y)

    def draw(self):
        screen.blit(self.image,(self.rect.x,self.rect.y)) 
start = Button(0,0,button1)


pygame.display.set_icon(icon)
while running == True:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            running = False
    start.draw()
    screen.blit(bg,(0,0))
    pygame.display.update()

我想要加载按钮。它不会给我错误，只是无法加载。

Answer 1

您必须在 screen.blit(bg,(0,0)) 之后、pygame.display.update 之前调用 start.draw() ()。注意:screen.blit(bg, (0,0) 在整个屏幕上绘制背景图像，这样之前绘制的所有内容都会被 overdraw 。pygame.display.update() 更新显示并使显示表面的所有更改立即可见:

while running == True:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            running = False

    # draw background
    screen.blit(bg,(0,0))

    # draw button
    start.draw()

    # update display
    pygame.display.update()