docking bug correction

src/main/java/fr/soleil/docking/vl/view/VlDockViewFactory.java

@@ -24,7 +24,10 @@ public class VlDockViewFactory extends AbstractViewFactory {
     @Override
     protected void updateViewForDockingArea(IView view, JComponent dockingArea) {
         if ((view instanceof VlDockView) && (dockingArea instanceof SoleilDockingDesktop)) {
-            ((VlDockView) view).setDockingDesktop((SoleilDockingDesktop) dockingArea);
+            VlDockView vlDockView = (VlDockView) view;
+            SoleilDockingDesktop dockingDesktop = (SoleilDockingDesktop) dockingArea;
+            dockingDesktop.addDockable(vlDockView);
+            vlDockView.setDockingDesktop(dockingDesktop);
         }
     }