The BarLayer class is a graphical object representing non visible layers added to a Bar.
There are no constructors for this class. BarLayers with the DFrame or Bar addBarLayer methods:
var barLayer = bar.addbarLayer(position, title, barStyle):
Some methods implicitly create the default BarLayer of a Bar:
var bar = dFrame.addBar()
var button = dFrame.addButton(parameters)
var menu = dFrame.addMenu(parameters)