title: pygame define different position order make the different result
body: <p>I define the different position order of my object, then I found it makes an error.</p>
  
  <ol>
  <li><p>I want to my <code>button_surface</code> on the center of the <code>screen</code> so I define<br />
  <code>self.button_surface_rect.center = self.setting.screen_rect.center</code></p></li>
  <li><p>Then make the <code>text_surface_rect</code> on the center of the <code>screen</code><br />
  <code>self.text_surface_rect.center = self.setting.screen_rect.center</code></p></li>
  <li><p>Put the <code>text_rect</code> on the center of the <code>text_surface</code><br />
  <code>self.text_rect.center = self.text_surface_rect.center</code></p></li>
  </ol>
  
  <p>When I blit the screen, there's no text on my text_surface, why?</p>
  
  <p>Here's the code:</p>
  
  <pre><code>#!/usr/bin/python
  import sys,os
  import pygame
  class Setting():
      def __init__(self,width,height):
          self.w=width
          self.h=height
          self.flag=pygame.RESIZABLE
          self.color=(255,255,255)
          self.screen=pygame.display.set_mode((self.w,self.h),self.flag)
          self.screen_rect=self.screen.get_rect()
          pygame.display.set_caption("Muhaha")
  
  
  class Button():
      def __init__(self,setting,text):
          self.setting = setting
          self.text_color=(0,0,255)
          self.button_color=(0,100,100)
  
          self.rect=pygame.Rect(0,0,400,100)
          self.rect.center = self.setting.screen_rect.center
  
          self.text=pygame.font.Font(None,80).render(text,True,self.text_color)
          self.text_surface=pygame.Surface((400,100))
          self.text_surface.set_colorkey((0,0,0)) 
  
          self.button_surface=pygame.Surface((400,100))
          self.button_surface.set_alpha(128)
  
          self.button_surface_rect = self.button_surface.get_rect()
          self.button_surface_rect.center = self.setting.screen_rect.center
  
          '''when i define this i cant see the textz'''
          self.text_surface_rect = self.text_surface.get_rect()
          self.text_surface_rect.center = self.setting.screen_rect.center
  
          self.text_rect = self.text.get_rect()
          print(self.text_rect)
          print(self.text_surface_rect)
          self.text_rect.center = self.text_surface_rect.center
          print(self.text_rect)
  
      def blit_button(self):
          self.button_surface.fill(self.button_color)
          self.setting.screen.blit(self.button_surface,self.button_surface_rect)
          self.text_surface.blit(self.text,self.text_rect)
          self.setting.screen.blit(self.text_surface,self.button_surface_rect)
  
  
  
  def game():
      pygame.init()
      setting=Setting(1200,800)
      button=Button(setting,'PLAY')
  
  
      while True:
          for event in pygame.event.get():
              if event.type == pygame.QUIT:
                  sys.exit()
          setting.screen.fill((255,0,0))
          button.blit_button()
          pygame.display.flip()
  game()
  </code></pre>