VkSimpleWindow and VkWindow classes provide simple functions to show, hide, raise, lower, iconify, and open windows. The following functions do not take arguments and return a void value:
show() Displays window and has no effect if window is currently iconified.
hide() Removes window from the screen.
iconify() Iconifies window.
open() Opens window if iconified.
raise() Raises window to top of application's window stack.
lower() Lowers window to bottom of application's window stack.
These functions are declared virtual. If overridden in a subclass, call the corresponding base class function after performing operations required by your subclass.