to a option with the specified label in the given combo.&nbsp; Combo is an object returned from an earlier call to <a href="#mxDefaultToolbar.addCombo" class=LFunction id=link54 onMouseOver="ShowTip(event, 'tt13', 'link54')" onMouseOut="HideTip('tt13')">addCombo</a> or <a href="#mxDefaultToolbar.addActionCombo" class=LFunction id=link55 onMouseOver="ShowTip(event, 'tt15', 'link55')" onMouseOut="HideTip('tt15')">addActionCombo</a>.</p><h4 class=CHeading>Parameters</h4><table border=0 cellspacing=0 cellpaddin