let menu: Duang = {
        let menu = Duang(
            frame: CGRect(x: 0, y: 50, width: UIScreen.main.bounds.width, height: 100),
            subControllers: [AVC.self, BVC.self, CVC.self],
            dataSource: self,
            delegate: self,
            controlBarHeight: 54,
            loadAllCtl: false,
            style: .full)
        menu.controlSpacing = 10.0
        menu.segmentHeight = 5.0
        return menu
    }()

// Return to the view on the control bar
func duangControlBar(itemForIndex index: Int) -> UIView 

// Invoke this method when initializing a controller
func duang(initialized ctl: UIViewController)

func duang(current ctl: UIViewController, page: Int)

func duang(current item: UIView)

func duang(didSelectControlBarAt index: Int)