func pinnedConstraints(view: UIView) -> [NSLayoutConstraint] {
        let topConstraint = NSLayoutConstraint(item: view, attribute: NSLayoutAttribute.Top, relatedBy: NSLayoutRelation.Equal, toItem: self.topLayoutGuide, attribute: NSLayoutAttribute.Bottom, multiplier: 1, constant: 0)
        let leftConstraint = NSLayoutConstraint(item: view, attribute: NSLayoutAttribute.Left, relatedBy: NSLayoutRelation.Equal, toItem: self.view, attribute: NSLayoutAttribute.Left, multiplier: 1, constant: 0)
        let rightConstraint = NSLayoutConstraint(item: view, attribute: NSLayoutAttribute.Right, relatedBy: NSLayoutRelation.Equal, toItem: self.view, attribute: NSLayoutAttribute.Right, multiplier: 1, constant: 0)
        let bottomConstraint = NSLayoutConstraint(item: view, attribute: NSLayoutAttribute.Bottom, relatedBy: NSLayoutRelation.Equal, toItem: self.bottomLayoutGuide, attribute: NSLayoutAttribute.Top, multiplier: 1, constant: 0)

        return [topConstraint, leftConstraint, bottomConstraint, rightConstraint]
    }