title: Can you add a sprite kit particle emitter to the background of a UIViewController?
body: <p>I'm new to sprite kit game development and I was wondering if it's possible to add a particle emitter to a UIViewController. I want to have buttons on the screen along with the particle emitter for an app idea I have which is the problem. There is no built in button object for SKScene, so I decided maybe it would be better to add a particle emitter to a UIViewController class instead. Is it possible to make a particle emitter in the background and to place buttons on top of it that way?</p>