public final ObjectProperty<EventHandler<Event>> onShownProperty() {
    return getDialogControl().onShownProperty();
  }
The dialog's action, which is invoked whenever the dialog has been fully initialized and is
being shown. Whenever the {@link DialogControl#dialogProperty()}, {@link
WorkbenchDialog#buttonTypes}, {@link DialogControl#buttonTextUppercaseProperty()} or {@link
DialogControl#workbenchProperty()} changes, the dialog will be rebuilt and upon completion, an
event will be fired.

@return the property to represent the event, which is invoked whenever the dialog has been
        fully initialized and is being shown.
workbenchfx-core/src/main/java/com/dlsc/workbenchfx/model/WorkbenchDialog.java