Add System Tray and Active Workbech Shell reference in E4 application - eclipse-rcp

Question

I am new in E4 application development. I add System tray icon in RCP 3.7.x successfully.
to add a system tray icon in e4 application. I am using the e4 application life cycle to add a system tray icon in this way:
public class LifeCycleManager {
#PostContextCreate
void postContextCreate(IApplicationContext appContext, Display display) {
SystemNotifier icon= new SystemNotifier(shell);
SystemNotifier.trayItem = icon.initTaskItem(shell);
if (SystemNotifier.trayItem != null) {
icon.hookPopupMenu();
}
}
}
How to get reference of Active Workbench Shell in e4 application.
Which annotation use of e4 application life cycle to add System Tray

Answer 1

The application shell is not available when #PostContextCreate runs. You need to wait for the application startup complete event, something like:
#PostContextCreate
void postContextCreate(IEclipseContext context, IEventBroker eventBroker)
{
eventBroker.subscribe(UIEvents.UILifeCycle.APP_STARTUP_COMPLETE, new AppStartupCompleteEventHandler(eventBroker, context));
}
private static final class AppStartupCompleteEventHandler implements EventHandler
{
private final IEventBroker _eventBroker;
private final IEclipseContext _context;
AppStartupCompleteEventHandler(IEventBroker eventBroker, IEclipseContext context)
{
_eventBroker = eventBroker;
_context = context;
}
#Override
public void handleEvent(final Event event)
{
_eventBroker.unsubscribe(this);
Shell shell = (Shell)_context.get(IServiceConstants.ACTIVE_SHELL);
... your code ...
}
}