 		if let vc = leftView {
 			let w: CGFloat = vc.width
 			let h: CGFloat = vc.height
-			let d: Double = Double(0 == velocity ? SideNavigationViewController.animationDuration : fmax(0.1, fmin(1, Double(vc.x / velocity))))
+			let d: Double = Double(0 == velocity ? animationDuration : fmax(0.1, fmin(1, Double(vc.x / velocity))))
 			
 			MaterialAnimation.animationWithDuration(d, animations: {
 				vc.position = CGPointMake(w / 2, h / 2)
+				self.backdropLayer.hidden = false
 			}) {
-				SideNavigationViewController.backdropLayer.hidden = false
 				self.isUserInteractionEnabled = false
 				self.toggleStatusBar(true)
 			}

			case .Began:
				originalPosition = v.position
				toggleStatusBar(true)
				SideNavigationViewController.backdropLayer.hidden = false
			case .Changed:
				let translation: CGPoint = recognizer.translationInView(v)
				let w: CGFloat = v.width

	/**
		:name:	horizontalThreshold
	*/
	public lazy var horizontalThreshold: CGFloat = 64
	
	/**
		:name:	animationDuration
	*/
	public lazy var animationDuration: CGFloat = 0.25
	
	//
	//	:name:	enabled
