There is class named TitleWindow which extends from the Panel
class, this class has a
showCloseButton property that activates or deactivates the
close button on the right top corner. You can use TitleWindow in
order to make a collapsable panel.
Curiously the Panel component has a "close" event that's
dispatched when the close button is pressed, but the Panel class
doesn't have a showCloseButton property or anything like that, just