save project

snake.py

-import pygame
+import pygame  
 from pygame import locals
-pygame.init()
-screen = pygame.display.set_mode((800,600))
-background = pygame.image.load('bg.png')
-food = pygame.image.load('apple.png')
+pygame.init() #初始化
+food = pygame.image.load('apple.png')  #图片初始化
 right = pygame.image.load('right.png')
-
+left = pygame.image.load('left.png')
+up = pygame.image.load('up.png')
+down = pygame.image.load('down.png')
+body = pygame.image.load('body.png')
+background = pygame.image.load('bg.png')
+screen = pygame.display.set_mode((800,600))  #创建窗口
+x = 180
+y = 180
+setheading = right
+position = [(x,y),(150,180),(120,180),(120,150)]   #设置位置列表
+fps = pygame.time.Clock()  #s设置一个计时器用来记录画面刷新的帧数
 while True:
-    for i in pygame.event.get():
-        if  i.type == locals.QUIT:
-            exit()
-    screen.blit(background,(0,0))
-    screen.blit(food,(180,180))
-    screen.blit(right,(150,180))
-    pygame.display.update()
\ No newline at end of file
+
+    for i in pygame.event.get(): #遍历pygame中的事件，优先处理事件
+        if i.type == locals.KEYDOWN:
+            if i.key == locals.K_w and setheading!=down: 
+                
+                setheading = up
+            elif i.key == locals.K_s and setheading!=up:
+                
+                setheading = down 
+            elif i.key == locals.K_a and setheading!=right:
+                
+                setheading = left
+            elif i.key == locals.K_d and setheading!=left:
+                
+                setheading = right
+    
+        if i.type == locals.QUIT:  #如果事件编号和locals中推出的编号一样
+            exit() #终止程序
+    if setheading == up:
+        y-=30
+    if setheading == down:
+        y+=30
+    if setheading == right:
+        x+=30
+    if setheading == left:
+        x-=30
+    screen.blit(background,(0,0)) #画背景
+    screen.blit(food,(300,300)) #画食物
+    screen.blit(setheading,position[0])
+    for i in range(1,len(position)):
+        screen.blit(body,position[i])
+    pygame.display.update() #刷新窗口
+    position.insert(0,(x,y))
+    position.pop(-1)
+    fps.tick(3)  #每秒刷新3帧