             dispatchEvent(new Event(type));
     }
     
+    private function maybeInvalidateGrid():void
+    {
+        if (grid)
+        {
+            grid.invalidateSize();
+            grid.invalidateDisplayList();
+        }
+    }
+    
     //----------------------------------
     //  grid
     //----------------------------------

        }
        
        dispatchChangeEvent("itemRendererChanged");
        
        // TBD invalidate grid    
    }
    
    //----------------------------------

            return;
        
        _width = value;
        
        maybeInvalidateGrid();

        dispatchChangeEvent("widthChanged");
    }
    
    //----------------------------------
