Bug 294750 [Contributions] Allow a handler to update MUIItems
A handler for a command should be able to update text or tooltips on UIItems that point to the command. ex: in 3.x we have this pattern. 1) each item registers as a UIElement for a command 2) the command service can handle a request to refresh all UIElements for a command 3) changing handlers causes a refresh request 4) the client code can also request a refresh We need a similar story for e4 that would allow the active handler to update the appropriate items. It is a little more complicated in e4 as depending on your location (part of the hierarchy you are requesting from) you will potentially have different handlers applicable to different MUIItems. PW
bundles/org.eclipse.e4.ui.workbench.renderers.swt/src/org/eclipse/e4/workbench/ui/renderers/swt/ToolItemRenderer.java
IEventBroker eventBroker;
	private EventHandler itemUpdater = new EventHandler() {
		public void handleEvent(Event event) {
			
			if (!(event.getProperty(UIEvents.EventTags.ELEMENT) instanceof MToolItem))
				return;
			MToolItem itemModel = (MToolItem) event
					.getProperty(UIEvents.EventTags.ELEMENT);
			ToolItem toolItem = (ToolItem) itemModel.getWidget();
			
			if (toolItem == null)
				return;
			String attName = (String) event
					.getProperty(UIEvents.EventTags.ATTNAME);
			if (UIEvents.UILabel.LABEL.equals(attName)) {
				setItemText(itemModel, toolItem);
			} else if (UIEvents.UILabel.ICONURI.equals(attName)) {
				toolItem.setImage(getImage(itemModel));
			} else if (UIEvents.UILabel.TOOLTIP.equals(attName)) {
				toolItem.setToolTipText(itemModel.getTooltip());
				toolItem.setImage(getImage(itemModel));
			}
		}
	};
	private EventHandler selectionUpdater = new EventHandler() {
		public void handleEvent(Event event) {
			
			if (!(event.getProperty(UIEvents.EventTags.ELEMENT) instanceof MToolItem))
				return;
			MToolItem itemModel = (MToolItem) event