Sector export: Hide empty Refinement Regions folder in project tree

Add shouldBeVisibleInTree() to RimRefinementRegionCollection (true only
when at least one region exists) and consult it from
RimEclipseView::defineUiTreeOrdering. Refresh the parent view's
connected editors from addNewRegion, removeRegion, and onChildDeleted so
the folder appears and disappears as regions are added or removed via
the generic delete-item action.

The "New Refinement Region" action remains reachable from the Eclipse
view's context menu while the folder is hidden.

ApplicationLibCode/ProjectDataModel/RimRefinementRegionCollection.cpp

@@ -51,6 +51,14 @@ bool RimRefinementRegionCollection::isActive() const
     return m_isActive();
 }
 
+//--------------------------------------------------------------------------------------------------
+///
+//--------------------------------------------------------------------------------------------------
+bool RimRefinementRegionCollection::shouldBeVisibleInTree() const
+{
+    return !m_regions.empty();
+}
+
 //--------------------------------------------------------------------------------------------------
 ///
 //--------------------------------------------------------------------------------------------------
@@ -86,6 +94,9 @@ RimRefinementRegion* RimRefinementRegionCollection::addNewRegion( RimEclipseCase
     region->setDefaultsFromCase( eclipseCase );
 
     updateConnectedEditors();
+    // Visibility of this collection in the parent view's tree depends on m_regions being non-empty,
+    // so refresh the parent so the folder appears when the first region is added.
+    if ( auto* view = firstAncestorOrThisOfType<Rim3dView>() ) view->updateConnectedEditors();
     return region;
 }
 
@@ -106,6 +117,17 @@ void RimRefinementRegionCollection::removeRegion( RimRefinementRegion* region )
     m_regions.removeChild( region );
     delete region;
     updateConnectedEditors();
+    if ( auto* view = firstAncestorOrThisOfType<Rim3dView>() ) view->updateConnectedEditors();
+}
+
+//--------------------------------------------------------------------------------------------------
+/// Refresh the parent view's tree so the collection folder disappears once the last region is
+/// removed via the generic delete-item action.
+//--------------------------------------------------------------------------------------------------
+void RimRefinementRegionCollection::onChildDeleted( caf::PdmChildArrayFieldHandle*      childArray,
+                                                    std::vector<caf::PdmObjectHandle*>& referringObjects )
+{
+    if ( auto* view = firstAncestorOrThisOfType<Rim3dView>() ) view->updateConnectedEditors();
 }
 
 //--------------------------------------------------------------------------------------------------