StarlingState is the right class to extend when using starling and view is available in StarlingState as well.
But because you are using a url for the view parameter instead of a starling Image or Texture, CE will try to load the asset and create the Texture/Image for you. The problem might come from here.
Accepting a url to load assets is a way to let us prototype games quickly , on desktop, where one might not have to worry too much about the assets yet.
But the right way to do things would be to load assets the starling way, with its AssetManager for example, and set the view parameter as a starling display object (Sprite, Image,MovieClip) or Texture (CE will create the Image for you).
There's no update to call, however the "view" might not appear in the same frame.
Which tutorial are you following?