上传文件至 ''

alien.py

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+import pygame
+from pygame.sprite import Sprite
+
+class Alien(Sprite):
+
+    def __init__(self,ai_game):
+        super().__init__()
+        self.screen = ai_game.screen
+        self.settings = ai_game.settings
+
+        self.image = pygame.image.load('images/alien.bmp')
+        self.rect = self.image.get_rect()
+
+        self.rect.x = self.rect.width
+        self.rect.y = self.rect.height
+
+        self.x = float(self.rect.x)
+
+    def check_edges(self):
+        screen_rect = self.screen.get_rect()
+        if self.rect.right >= screen_rect.right or self.rect.left <= 0:
+            return True
+
+    def update(self):
+        self.x += (self.settings.alien_speed *
+                   self.settings.fleet_direction)
+        self.rect.x = self.x