If neither the DragContext resources nor the Screen resources are specified, Motif uses hard−coded default icons. For
example, the running figure shown in the figure is used as the source icon whenever a source icon has not been
specified. Since this icon is rather arbitrary, you might want to set the XmN-defaultSourceCursorIcon
resource to something more appropriate for your application.
Before you can set the Screen resources in application code, you must create DragIcon objects for the different
resources. In Section #screateicon we describe how to create a drag icon using XmCreateDragIcon(). Once the
drag icon exists, you can retrieve the Screen object using XmGetXmScreen() and set its resources, as shown in the
following code fragment:
Widget drag_icon, screen, toplevel;
...
screen = XmGetXmScreen (XtScreen (toplevel));
XtVaSetValues (screen, XmNdefaultSourceCursorIcon, drag_icon, NULL);
...
The specified icon is used whenever the source icon has not been set for the DragContext for a drag and drop transfer.
The Screen resources can also be set in a resource file. In this case, the icons can be specified as bitmap files, so the
application does not have to create DragIcon objects. Both the icon and an optional mask can be specified using
resources as follows:
*defaultSourceCursorIcon.pixmap: icon.xbm
*defaultSourceCursorIcon.mask: icon_mask.xbm
Although it is convenient to be able to set the Screen resources in a resource file, this feature really isn't that useful
since the Motif widgets ...