Bug 180864 Change Allow Null option in Cascading Group.[0705]
Description: Change Allow Null option in Cascading Group. Build number:2.2.0.v20070404 Steps to reproduce: 1. New a cascading group and add sub parameter. Expected result: Is Required option in cascading group definition dialog. Actual result: Allow null value option in Cascading Group definition dialog Error log:N/A
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/CascadingParametersDialog.java
column.setText( columns[i] );
			column.setWidth( columnWidths[i] );
		}
		table.setLayoutData( data );
		valueTable = new TableViewer( table );
		valueTable.setCellEditors( cellEditors );
		valueTable.setColumnProperties( columns );
		valueTable.setContentProvider( contentProvider );
		valueTable.setLabelProvider( labelProvider );
		valueTable.setCellModifier( cellModifier );
		valueTable.addSelectionChangedListener( new ISelectionChangedListener( ) {
			public void selectionChanged( SelectionChangedEvent event )
			{
				ISelection selection = event.getSelection( );
				Object param = ( (StructuredSelection) selection ).getFirstElement( );
				if ( param != selectedParameter )
				{
					if ( param instanceof ScalarParameterHandle )
					{
						try
						{
							saveParameterProperties( );
							selectedParameter = (ScalarParameterHandle) param;
						}
						catch ( SemanticException e )
						{
							ExceptionHandler.handle( e );
							valueTable.setSelection( new StructuredSelection( selectedParameter ) );
						}
						refreshParameterProperties( );