gtk.gdk.Atom

gtk.gdk.Atom — an object representing an interned string

Synopsis

class gtk.gdk.Atom:
    gtk.gdk.atom_intern(name, only_if_exists=FALSE)

Description

gtk.gdk.Atom is a PyGTK class that wraps the GTK+ GdkAtom - an unsigned integer representing an interned string. An interned string is a string that has an internal GTK+ mapping between an atom and a string. gtk.gdk.Atom has no methods. A copy of the interned string can be retrieved by using the Python str() function. gtk.gdk.atom_intern() will return a gtk.gdk.Atom referencing an existing interned string but will intern a string if it isn't already interned.

gtk.gdk.Atom objects are used to provide the targets for gtk.SelectionData objects that are used by gtk.Clipboard and gtk.TreeView, objects and for drag and drop (see gtk.gdk.DragContext, gtk.gdk.Window and gtk.TreeDragSource and gtk.Widget for more information). The advantage of the interned string is that it is easy to pass between processes and even systems since only an integer value is passed.

PyGTK 2.4 has a number of pre-defined atoms that map to builtin GTK+ interned string atoms. The interned strings and the PyGTK 2.4 gtk.gdk.Atom objects are:

"PRIMARY"gtk.gdk.SELECTION_PRIMARY
"SECONDARY"gtk.gdk.SELECTION_SECONDARY
"CLIPBOARD"gtk.gdk.SELECTION_CLIPBOARD
"ATOM"gtk.gdk.SELECTION_TYPE_ATOM
"BITMAP"gtk.gdk.TARGET_BITMAP or gtk.gdk.SELECTION_TYPE_BITMAP
"COLORMAP"gtk.gdk.TARGET_COLORMAP or gtk.gdk.SELECTION_TYPE_COLORMAP
"DRAWABLE"gtk.gdk.TARGET_DRAWABLE or gtk.gdk.SELECTION_TYPE_DRAWABLE
"PIXMAP"gtk.gdk.TARGET_PIXMAP or gtk.gdk.SELECTION_TYPE_PIXMAP
"STRING"gtk.gdk.TARGET_STRING or gtk.gdk.SELECTION_TYPE_STRING
"WINDOW"gtk.gdk.SELECTION_TYPE_WINDOW

Also in PyGTK 2.4, comparison between a string and a gtk.gdk.Atom is supported.

Constructor

    gtk.gdk.atom_intern(name, only_if_exists=FALSE)
name :the string to be interned or retrieved
only_if_exists :this value is ignored
Returns :a new gtk.gdk.Atom or None

Creates a gtk.gdk.Atom referencing the interned string specified by name. An interned string is a string that has a GTK+ mapping to an unsigned integer value. This constructor will intern the string and create a gtk.gdk.Atom if it does not already exist. only_if_exists is ignored and essentially is always FALSE.