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
Assert.isNotNull( tree );
		tree.addMouseListener( new MouseAdapter( ) {
			public void mouseDoubleClick( MouseEvent event )
			{
				TreeItem[] selection = getTreeSelection( );
				if ( selection == null || selection.length <= 0 )
					return;
				TreeItem item = selection[0];
				if ( item != null )
				{
					Object obj = item.getData( ITEM_DATA_KEY_TEXT );
					Boolean isEnabled = (Boolean) item.getData( ITEM_DATA_KEY_ENABLED );
					if ( obj != null && isEnabled.booleanValue( ) )
					{
						String text = (String) obj;
						insertText( text );
					}
				}
			}
		} );
	}
	protected TreeItem[] getTreeSelection( )
	{
		return tree.getSelection( );
	}
	/**
	 * Adds drag support to tree..Must set tree before execution.
	 */
	public void addDragSupportToTree( )
	{