swift 代码加载xib storyboard

override init(nibName nibNameOrNil: String?, bundle nibBundleOrNil: NSBundle?){
super.init(nibName: nibNameOrNil, bundle: nibBundleOrNil)
}

convenience init() {
var nibNameOrNil = String?("ViewController")
self.init(nibName: nibNameOrNil, bundle: nil)
}

required init(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}

var jumpViewController: ViewController
= UIStoryboard(name: "Main", bundle: nil).instantiateViewControllerWithIdentifier("Storyboard ID") as! ViewController
self.navigationController?.pushViewController(jumpViewController, animated: true)