Navigator: Show Projects after startup.

* Since migrating to Photon, the listeners of the IPersistencyService
  must be seemingly installed in the init phase. By that, the
  corresponding listeners are also aware of model loading.
* Also, remove an unneeded cast to avoid a warning.

Issue-Ref: 3540
Issue-Url: https://af3-developer.fortiss.org/issues/3540

Signed-off-by: Alexander Diewald <diewald@fortiss.org>

org.fortiss.tooling.kernel.ui/src/org/fortiss/tooling/kernel/ui/internal/.ratings

@@ -7,6 +7,6 @@ EditPartFactoryService.java e9180c0020f1769d9e24ef3c08f9ca5599dbc5c3 GREEN
 MarkerService.java b01b7706034691683df7bbc2e7828c42574b3147 GREEN
 ModelEditorBindingService.java 4c2b52008025db79b1ced4b695d60b561d17c51e GREEN
 ModelElementHandlerService.java 07a30545ad687ff0fe13bf7a9348c41fb03e0b2c GREEN
-NavigatorService.java 8ba9cec9ee7b3a73a47303575df917f47f2f7754 GREEN
+NavigatorService.java 2b1361eac805996e22e5409dafff9707fbac3376 YELLOW
 ToolingKernelUIInternal.java 38903445a9084b7908716a00f41621dfb3126fca GREEN
 TutorialUIService.java b1d632eca91b4feb583f3930cd6ee4722dd9bfed GREEN

org.fortiss.tooling.kernel.ui/src/org/fortiss/tooling/kernel/ui/internal/NavigatorService.java

@@ -94,7 +94,7 @@ public class NavigatorService implements INavigatorService, IPersistencyServiceL
 
 	/** Initializes the service. */
 	public void initializeService() {
-		// nothing to do here
+		IPersistencyService.getInstance().addTopLevelElementListener(this);
 	}
 
 	/** Starts the service. */
@@ -103,7 +103,6 @@ public class NavigatorService implements INavigatorService, IPersistencyServiceL
 			ICommandStackService.getInstance().addCommandStackListener(element, this);
 			saveables.put(element, new TopLevelElementSaveable(element));
 		}
-		IPersistencyService.getInstance().addTopLevelElementListener(this);
 		ITutorialService.getInstance().addTutorialServiceListener(this);
 	}
 
@@ -154,12 +153,17 @@ public class NavigatorService implements INavigatorService, IPersistencyServiceL
 	/** {@inheritDoc} */
 	@Override
 	public void topLevelElementLoaded(ITopLevelElement element) {
-		// ignore
+		addTopLevelElementScheduled(element);
 	}
 
 	/** {@inheritDoc} */
 	@Override
 	public void topLevelElementAdded(final ITopLevelElement element) {
+		addTopLevelElementScheduled(element);
+	}
+
+	/** Adds the given {@link ITopLevelElement} to the Navigator and updates the view. */
+	private void addTopLevelElementScheduled(final ITopLevelElement element) {
 		new UIJob("NavigatorServiceSafeableRefresh") {
 			@Override
 			public IStatus runInUIThread(IProgressMonitor monitor) {
@@ -328,8 +332,8 @@ public class NavigatorService implements INavigatorService, IPersistencyServiceL
 	private void saveablesChanged(int event, ITopLevelElement element, boolean force) {
 		Saveable saveable = saveables.get(element);
 		if(saveable != null && navigatorViewPart != null) {
-			ISaveablesLifecycleListener listener = (ISaveablesLifecycleListener)PlatformUI
-					.getWorkbench().getService(ISaveablesLifecycleListener.class);
+			ISaveablesLifecycleListener listener =
+					PlatformUI.getWorkbench().getService(ISaveablesLifecycleListener.class);
 			SaveablesLifecycleEvent eventObj = new SaveablesLifecycleEvent(navigatorViewPart, event,
 					new Saveable[] {saveable}, force);
 			listener.handleLifecycleEvent(eventObj);