title: No physics with Scene Editor and custom SKSpriteNode subclass
body: <p>When I set my scene’s node to my <code>SKSpriteNode</code> subclass in the scene editor’s Custom Class inspector, the node works as expected (after implementing the <code>init(coder:_)</code> method) apart from the physics body on the node.</p>
  
  <p>Here is a screenshot of the node’s Attributes Inspector:</p>
  
  <p><a href="https://i.stack.imgur.com/9NRNO.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/9NRNO.png" alt="Attributes Inspector"></a></p>
  
  <p>I notice the Physics Definition is clearly set to none. But as you can see in my <code>SKSpriteNode</code>’s subclass’s init methods, I setup the physics body here:</p>
  
  <pre><code>required init()
  {
      //  Super
      super.init(texture: nil, color: MyColour, size: MySize)
  
      //  Setup the bubble node
      _setupBubbleNode()
  }
  
  required init?(coder aDecoder: NSCoder)
  {
      super.init(coder: aDecoder)
  
      //  Setup the bubble node
      _setupBubbleNode()
  }
  
  private func _setupBubbleNode()
  {
      //  Properties...
      /// setup stuff...
  
      //      Physics body
      physicsBody = SKPhysicsBody(circleOfRadius: _radius)
      physicsBody!.mass = _bubbleMass
      physicsBody!.linearDamping = 20
      physicsBody!.angularDamping = 1
      physicsBody!.restitution = 0.2
      physicsBody!.allowsRotation = false
      physicsBody!.affectedByGravity = true
  
  
      //  Other stuff...
      /// setup stuff...
  }
  </code></pre>
  
  <p>Note: I should also add that when programatically adding a new instance of my sprite, the physics works… </p>