public interface SGWTProperties

APIs such as ListGrid.setHeaderButtonproperties() or FormItem.setDefaultProperties() are properties APIs - they can be passed a Canvas or FormItem instance as a "properties object": a means of configuring an AutoChild or establishing new defaults for the class.

When calling a properties API:

all settings applied to the properties object are copied when the properties API is called. Subsequent changes to the properties object are ignored.
the properties object is not a real widget; it's essentially just a type-safe API for establishing default properties. Only calls to simple Java Bean-style setters are generally supported, and in the case of AutoChildren, event registrations (addSomethingHandler()). It's invalid to BaseWidget.draw() a properties object, ask it to fetch data, or in any other way treat it like a real widget.
similarly you cannot take a live widget and pass it to a properties API. For example, you cannot take a Button that has already been drawn and pass it a properties API
the properties object is not a live link to whatever AutoChild or other component is configured by those properties. For example, if you use Window.changeAutoChildDefaults("header", headerProperties) to affect the window "header" AutoChild, you cannot later call Canvas.setBorder() on the headerProperties object to affect the header border. You would call Window.getHeader() to get the live header object instead.
it is valid for a Canvas-based properties object to be further modified and passed to a second properties API on some other object, however it is not valid to do this with a FormItem-based properties object or DataClass-based properties object (such as ListGridField).

See Also:

Interface SGWTProperties