GtkSocket

Object Hierarchy

  GtkObject
   +----GtkWidget
         +----GtkContainer
               +----GtkSocket

Description

Together with GtkPlug, GtkSocket provides the ability to embed widgets from one process into another process in a fashion that is transparent to the user. One process creates a GtkSocket widget and, passes the XID of that widget's window to the other process, which then creates a GtkPlug window with that XID. Any widgets contained in the GtkPlug then will appear inside the first applications window.

The XID of the socket's window is obtained by using the GTK_WINDOW_XWINDOW() macro from the header file <gdk/gdkx.h>. Before using this macro, the socket must have been realized, and for hence, have been added to its parent.

include <gdk/gdkx.h>

GtkWidget *socket = gtk_socket_new();
gtk_widget_show (socket);
gtk_container_add (GTK_CONTAINER (parent), socket);

/* The following call is only necessary if one of
 * the ancestors of the socket is not yet visible.
 */
gtk_widget_realize (socket);
g_print ("The XID of the sockets window is %x\n",
         GDK_WINDOW_XWINDOW (socket->window));

Note that if you pass the XID of the socket to another process that will create a plug in the socket, you must make sure that the socket widget is not destroyed until that plug is created. Violating this rule will cause unpredictable consequences, the most likely consequence being that the plug will appear as a separate toplevel window. You can check if the plug has been created by examining the plug_window field of the GtkSocket structure. If this field is non-NULL, then the plug has been succesfully created inside of the socket.

When GTK+ is notified that the embedded window has been destroyed, then it will destroy the socket as well. You should always, therefore, be prepared for your sockets to be destroyed at any time when the main event loop is running.

A socket can also be used to swallow arbitrary pre-existing top-level windows using gtk_socket_steal(), though the integration when this is done will not be as close as between a GtkPlug and a GtkSocket.

Details

struct GtkSocket;

GtkWidget*  gtk_socket_new                  (void);

void        gtk_socket_steal                (GtkSocket *socket,
                                             guint32 wid);

See Also