If true, then this dialog displays an Apply button.
If $NAMESPACE is set, auto switch namespace
DOCBOOK Topic Id that offers help for this page.
Get the (localized) subtitle string for the dialog. This should be implemented in a subclass.
Get the (localized) title string for the dialog. This should be implemented in a subclass.
Get the value that will be applied when the user presses the OK button. This is implemented by subclasses.
Show definition based on type This callback, if defined, is called when the user presses the OK or Apply action buttons. If this returns false, then the action is cancelled.