text: #!/usr/bin/env python3
  
  import glooey
  
  def test_scroll_box_scale_grip_no_child():
      # It should not be an error to attach a scroll box with a scaled grip and 
      # no child to the GUI.  This means the scroll box needs to hold off 
      # calculating how big its grip should be if it's attached before it has a 
      # child.  See #36.
  
      class TestWindow:
  
          def __init__(self):
              self.width = 600
              self.height = 480
  
          def push_handlers(self, listener):
              pass
  
      class TestScrollBox(glooey.ScrollBox):
       
          class VBar(glooey.VScrollBar):
              custom_scale_grip = True
  
              class Grip(glooey.Button):
                  pass
  
      win = TestWindow()
      gui = glooey.Gui(win)
  
      scroll = TestScrollBox()
      gui.add(scroll)
  