Volume 6A: Motif Programming Manual

Arg args[10];

int n;

Widget label;

Atom importList[1];

void HandleDrop();

...

n = 0;

importList[0] = COMPOUND_TEXT;

XtSetArg (args[n], XmNimportTargets, importList); n++;

XtSetArg (args[n], XmNnumImportTargets, XtNumber (importList)); n++;

XtSetArg (args[n], XmNdropSiteOperations, XmDROP_COPY); n++;

XtSetArg (args[n], XmNdropProc, HandleDrop); n++;

XmDropSiteRegister (label, args, n);

When a drop occurs in the drop site, the XmN-dropProc is called automatically by the Motif toolkit. This routine

must call XmDropTransferStart() whether or not the drop is -successful. XmDropTransferStart()

creates a DropTransfer object that maintains information about the data transfer. When The DropTransfer object is

created, the XmN-transferStatus resource must be set to indicate the success or failure of the drop. If the

resource is set to XmTRANSFER_FAILURE, XmDropTransferStart() does not transfer any data and merely

cleans up after the drag and drop transfer.

If XmN-transferStatus is set to XmTRANSFER_SUCCESS when the DropTransfer object is created, some other

resources must also be specified to cause the data to be transferred. The XmN-dropTransfers and

XmN-numDropTransfers resources specify the data targets to be processed, while XmN-transferProc

indicates the procedure that receives the converted data from the drag source. This procedure is of type

XtSelectionCallbackProc. Once the data transfer has started, XmDropTransferAdd() can be used to

request the processing of additional data targets. In ...