function update(oControl, aContexts) {
			var aChildren = oControl.getItems() || [],
				oContext,
				oClone;

			if (aChildren.length > aContexts.length) {
				for (var i = aContexts.length; i < aChildren.length; i++) {
					oControl.removeItem(aChildren[i]);
					aChildren[i].destroy("KeepDom");
				}
			}
			for (var i = 0; i < aContexts.length; i++) {
				oContext = aContexts[i];
				oClone = aChildren[i];
				if (oClone) {
					oClone.setBindingContext(oContext, oBindingInfo.model);
				} else {
					oClone = fnFactory(oControl.getId() + "-" + i, oContext);
					oClone.setBindingContext(oContext, oBindingInfo.model);
					oControl.addItem(oClone);
				}
			}

		}
Flag that indicates whether the item has been expanded or collapsed