* layout performance improvement

* minor fix in WEditorPopupMenu

zkwebui/WEB-INF/src/org/adempiere/webui/component/GridPanel.java

@@ -73,16 +73,19 @@ public class GridPanel extends Borderlayout implements EventListener
 
 	private GridTabListItemRenderer renderer;
 
+	private South south;
+	
 	public GridPanel()
 	{
-		super();
+		this(0);
-		listbox = new Listbox();
 	}
 	
 	public GridPanel(int windowNo)
 	{
 		this.windowNo = windowNo;
 		listbox = new Listbox();
+		south = new South();
+		this.appendChild(south);
 	}
 	
 	public void init(GridTab gridTab)
@@ -225,21 +228,11 @@ public class GridPanel extends Borderlayout implements EventListener
 			paging.setPageSize(pageSize);
 			paging.setTotalSize(tableModel.getRowCount());
 			paging.setDetailed(true);
-			South south = new South();
 			south.appendChild(paging);
-			this.appendChild(south);
 			paging.addEventListener(ZulEvents.ON_PAGING, this);
-			//workaround for layout problem
-			this.setVisible(false);
-			Clients.response(new AuEcho(this, "postRender", null));
-		}		
-	}
-	
-	public void postRender()
-	{
-		this.setVisible(true);
 			this.getParent().invalidate();
 		}		
+	}
 	
 	private void updateModel() {
 		listModel = new GridTableListModel((GridTable)tableModel, windowNo);		

zkwebui/WEB-INF/src/org/adempiere/webui/editor/WEditorPopupMenu.java

@@ -121,6 +121,7 @@ public class WEditorPopupMenu extends Menupopup implements EventListener
     
     public void addMenuListener(ContextMenuListener listener)
     {
+    	if (!menuListeners.contains(listener))
     		menuListeners.add(listener);
     }