title: change background in pygame
body: <p>For some reason, my background does not change and my game does not start when the space bar is pressed.  I am not receiving any errors, the program just isn't working correctly.  Please help.</p>
  
  <pre><code>def main():
      title = games.load_image("contratitle.bmp",transparent = False)
      games.screen.background = title
      cursor = Cursor()
      games.screen.add(cursor)
      xd = 0
      if games.keyboard.is_pressed(games.K_q):
          xd = 1        
          while xd == 1:
              screen = games.load_image("jungle.bmp", transparent = False)
              games.screen.background = screen
              file2 = 'contra.mp3'
              pygame.mixer.music.load(file2)
              pygame.mixer.music.play()
              rizer = Rizer()
              games.screen.add(rizer)
              runner = Runner()
              games.screen.add(runner)
              shooter = Shooter()
              games.screen.add(shooter)
              spreadpower = Spreadp()
              #games.screen.add(spreadpower)
              rizerlives = Rizerlives()
              games.screen.add(rizerlives)
              rizerlivesa = Rizerlivesa()
              games.screen.add(rizerlivesa)
              #bean = Bean()
              #games.screen.add(bean)
      games.screen.mainloop()
  main()
  </code></pre>
  
  <p>Then, I tried to use pygame.display.update(), but that didn't work either.  Am I putting it in the wrong place?</p>
  
  <pre><code>def main():
      screen = games.load_image("contratitle.bmp",transparent = False)
      games.screen.background = screen
      cursor = Cursor()
      games.screen.add(cursor)
      xd = 0
      if games.keyboard.is_pressed(games.K_SPACE):
          xd = 1
          while xd == 1:
              screen = games.load_image("jungle.bmp", transparent = False)
              games.screen.background = screen
              file2 = 'contra.mp3'
              pygame.mixer.music.load(file2)
              pygame.mixer.music.play()
              rizer = Rizer()
              games.screen.add(rizer)
              pygame.display.update()
      games.screen.mainloop()
  main()
  </code></pre>