| GType {RGtk2} | R Documentation |
"The GType API is the foundation of the GObject system. It provides the facilities for registering and managing all fundamental data types, user-defined object and interface types." - GObject documentation
gTypeGetAncestors(type) gTypeGetInterfaces(type) gTypeFromName(name) gTypeGetClass(type)
type |
The GType, either its name or numeric value, see below |
name |
The name of a GType |
The GType system supports inheritance and interfaces, enabling the
psuedo-object-oriented system known as GObject. However, they
also encompass all fundamental (primitive) types.
A GType is considered a transparent-type in RGtk2, since
you may specify one as either the type name or the numeric value retrieved from
some API function like gTypeFromName. The GType system
obviously names primitive types different from the corresponding types in R,
but this is automatically taken care of for you, so you can use R type names (ie,
"character", "logical", etc) when specifying a GType. This means that
gTypeFromName is not that useful to the RGtk2 programmer.
All R objects representing external RGtk2 objects have their hierarchy stored in the
class attribute. Everything descends from "RGtkObject", then, for example, "GObject",
etc. The types do not necessarily correspond to GTypes, but they do for all
GObjects and others. Thus, gTypeGetAncestors is also of little use
unless one is working with pure GTypes.
gTypeGetAncestors returns a vector of type names from which type inherits.
gTypeGetInterfaces names the interfaces implemented by type.
gTypeFromName retrieves the numeric value of a type from its name.
gTypeGetClass returns the class instance for the type, for example GtkWidgetClass.
Michael Lawrence
http://developer.gnome.org/doc/API/2.0/gobject/gobject-Type-Information.html