Kernel: updated LWFXEFF for viewer customization.

Issue-Ref: 3815
Issue-Url: https://af3-developer.fortiss.org/issues/3815Signed-off-by: Florian Hoelzl <hoelzl@fortiss.org>

org.fortiss.tooling.kernel.ui/src/org/fortiss/tooling/kernel/ui/extension/base/.ratings

@@ -7,7 +7,7 @@ EReferencePropertySectionBase.java 0548da6778516003257f59d0b4c2b60d458be3b6 GREE
 EditorBase.java 9c09fff92945256bb8680992ae7bb2c78f47b150 GREEN
 FXEditorBase.java 2e520be0bbae7d0aebdff70218a124dbe0896ce2 YELLOW
 IListPropertySection.java 8bb00fe7959583e794ff9437b7a77404c9a9e70f GREEN
-LWFXEFEditorBase.java deabdd92833c75ffcc43bcc5eab05c4d74164b6d YELLOW
+LWFXEFEditorBase.java 5aa3971c06da012c2c2d84d5858b5f977dc6dd8b YELLOW
 ModelEditorBindingBase.java 4c5ac569c0b6e7678fc8191096b26dfd09fdcb98 GREEN
 ModelElementHandlerBase.java 384727748f125c9d43f19d9c0eba4ba1be5a7a26 GREEN
 MultiEObjectActionBase.java 9e237d8ea640c4194e4877af4a9cfce88698e543 GREEN

org.fortiss.tooling.kernel.ui/src/org/fortiss/tooling/kernel/ui/extension/base/LWFXEFEditorBase.java

@@ -39,9 +39,15 @@ public abstract class LWFXEFEditorBase<T extends EObject> extends FXEditorBase<T
 				createControllerFactory(), cb -> {
 					modelSelected(cb);
 				});
+		customizeViewer();
 		return viewer.getVisualNode();
 	}
 
+	/** Customize the viewer after it is created. The default implementation changes nothing. */
+	protected void customizeViewer() {
+		// the default does nothing
+	}
+
 	/** Create the {@link IModelFactory}. */
 	protected abstract IModelFactory createModelFactory();