Volume 6A: Motif Programming Manual

sites for graphical data. However, when these components are in a menu, they do not function as drag sources. These

components are not drop sites because they are meant to be read−only components in a user interface. Most

applications would not want the user to be able to change the label on a button by dropping text on it. However, if you

want to provide this type of functionality, it is easy to register a Label or a button as a drop site using the technique we

describe in Section #sdropsite.

The user can drag the text of either a single item or the current selection in a List widget. If the pointer is over a

selected item when the drag is started, the text of the selected item is used for the drag. If multiple items are selected,

the text of all of the selected items is used, where the items are separated by newlines. If the drag is started over an

unselected item, the text of that item is transferred by drag and drop. The List widget is not a drop site because its

items are not meant to be modified by the user. If you want to allow the user to modify a List by dropping items in it,

however, you can register the widget as a drop site.

The Text and TextField widgets are the only Motif widgets that have built−in drop site functionality. The user can

drop textual data from any drag source in these widgets. The widgets also function as drag sources, so the user can

move and copy the current selection within and between Text and TextField widgets.

Applications that simply use the built−in drag ...