content: 'Entry point of  MainScene
  sub Init()
      m.top.backgroundColor = "0x662D91"
      m.top.backgroundUri= "pkg:/images/background_marvel.jpg"
      m.loadingIndicator = m.top.FindNode("loadingIndicator")
      spinner = m.top.FindNode("spinner")
  	m.loadingIndicator.poster.uri="pkg:/images/loader.png"
      InitScreenStack()
      ShowGridScreen()
  end sub
  
  function OnkeyEvent(key as String, press as Boolean) as Boolean
      result = false
      if press
          if key = "back"
              numberOfScreens = m.screenStack.Count()
              ' close top screen if there are two or more screens in the screen stack
              if numberOfScreens > 1
                  CloseScreen(invalid)
                  result = true
              end if
          end if
      end if
  
      return result
  end function
  