Function CanvasSelectTo

micropolis-activity/src/tk/tkcanvas.c:3166–3212

(canvasPtr, itemPtr, index)

	EventuallyRedrawArea(canvasPtr, canvasPtr->focusItemPtr->x1,
		canvasPtr->focusItemPtr->y1, canvasPtr->focusItemPtr->x2,
		canvasPtr->focusItemPtr->y2);
    }
}


/*
 *----------------------------------------------------------------------
 *
 * CanvasSelectTo --
 *
 *	Modify the selection by moving its un-anchored end.  This could
 *	make the selection either larger or smaller.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	The selection changes.
 *
 *----------------------------------------------------------------------
 */

static void
CanvasSelectTo(canvasPtr, itemPtr, index)
    register Tk_Canvas *canvasPtr;		/* Information about widget. */
    register Tk_Item *itemPtr;		/* Item that is to hold selection. */
    int index;				/* Index of element that is to
					 * become the "other" end of the
					 * selection. */
{
    int oldFirst, oldLast;
    Tk_Item *oldSelPtr;

    oldFirst = canvasPtr->selectFirst;
    oldLast = canvasPtr->selectLast;
    oldSelPtr = canvasPtr->selItemPtr;

    /*
     * Grab the selection if we don't own it already.
     */

    if (canvasPtr->selItemPtr == NULL) {
	Tk_OwnSelection(canvasPtr->tkwin, CanvasLostSelection,
		(ClientData) canvasPtr);
    } else if (canvasPtr->selItemPtr != itemPtr) {
	EventuallyRedrawArea(canvasPtr, canvasPtr->selItemPtr->x1,
		canvasPtr->selItemPtr->y1, canvasPtr->selItemPtr->x2,
		canvasPtr->selItemPtr->y2);
    }
    canvasPtr->selItemPtr = itemPtr;