content: sub init()
      m.group = m.top.findNode("group")
      m.groupbutton = m.top.findNode("groupButton")
      m.groupbutton.buttons = ["Hide Image","Show Image"]
      m.groupbutton.observefield("buttonSelected","onButtonSelected")
      m.top.setFocus(true)
  end sub
  
  function onButtonSelected()
      if m.groupbutton.buttonSelected = 0
          m.group.visible = false
      elseif m.groupbutton.buttonSelected = 1
          m.group.visible = true
      endif
  end function