Bug 122869 Drag a parameter from data explorer view into a table in library, a new parameter is created automatically.
Description:Drag a parameter from data explorer view into a table in library, a new parameter is created automatically. Steps to reproduce: 1. Add a cascading parameter and a table in a library file. 2. Drag a parameter from data explorer view into a table cell in layout editor. 3. Find that a new parameter was added in data explorer view automatically.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/internal/ui/dialogs/ExpressionTreeSupport.java
DataSetHandle handle = (DataSetHandle) iterator.next( );
			TreeItem dataSetItem = createSubTreeItem( topItem,
					DEUtil.getDisplayLabel( handle, false ),
					ReportPlatformUIImages.getImage( handle ),
					true );
			DataSetItemModel[] columns = DataSetManager.getCurrentInstance( )
					.getColumns( handle, false );
			for ( int i = 0; i < columns.length; i++ )
			{
				createSubTreeItem( dataSetItem,
						columns[i].getDisplayName( ),
						IMAGE_COLUMN,
						DEUtil.getExpression( columns[i] ),
						columns[i].getHelpText( ),
						true );
			}
		}
	}
	/**
	 * Creates birt object tree. Must set Tree before execution.
	 * 
	 */
	public void createBirtObjectsTree( )
	{
		Assert.isNotNull( tree );
		TreeItem topItem = createTopTreeItem( tree, TREE_ITEM_BIRT_OBJECTS );
		createObjects( topItem, OBJECTS_TYPE_BIRT );
	}
	/**
	 * Creates a top tree item