Function DisplayMenuButton

micropolis-activity/src/tk/tkmnbut.c:751–904

(clientData)

 * Side effects:
 *	Commands are output to X to display the menubutton in its
 *	current mode.
 *
 *----------------------------------------------------------------------
 */

static void
DisplayMenuButton(clientData)
    ClientData clientData;	/* Information about widget. */
{
    register MenuButton *mbPtr = (MenuButton *) clientData;
    GC gc;
    Tk_3DBorder border;
    Pixmap pixmap;
    int x = 0;			/* Initialization needed only to stop
				 * compiler warning. */
    int y;
    register Tk_Window tkwin = mbPtr->tkwin;

    mbPtr->flags &= ~REDRAW_PENDING;
    if ((mbPtr->tkwin == NULL) || !Tk_IsMapped(tkwin)) {
	return;
    }

    if ((mbPtr->state == tkDisabledUid) && (mbPtr->disabledFg != NULL)) {
	gc = mbPtr->disabledGC;
	border = mbPtr->normalBorder;
    } else if (mbPtr->state == tkActiveUid) {
	gc = mbPtr->activeTextGC;
	border = mbPtr->activeBorder;
    } else {
	gc = mbPtr->normalTextGC;
	border = mbPtr->normalBorder;
    }

    /*
     * In order to avoid screen flashes, this procedure redraws
     * the menu button in a pixmap, then copies the pixmap to the
     * screen in a single operation.  This means that there's no
     * point in time where the on-sreen image has been cleared.
     */

    pixmap = XCreatePixmap(Tk_Display(tkwin), Tk_WindowId(tkwin),
	    Tk_Width(tkwin), Tk_Height(tkwin),
	    Tk_DefaultDepth(Tk_Screen(tkwin)));
    Tk_Fill3DRectangle(Tk_Display(tkwin), pixmap, border,
	    0, 0, Tk_Width(tkwin), Tk_Height(tkwin), 0, TK_RELIEF_FLAT);

    /*
     * Display bitmap or text for button.
     */

    if (mbPtr->bitmap != None) {
	unsigned int width, height;

#if defined(USE_XPM3)
	Tk_SizeOfPixmap(mbPtr->bitmap, &width, &height);
#else
	Tk_SizeOfBitmap(mbPtr->bitmap, &width, &height);