Bug 128317 group header and footer checkboxes
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/GroupDialog.java
nameEditor = new Text( composite, SWT.SINGLE | SWT.BORDER );
		nameEditor.setLayoutData( new GridData( GridData.FILL_HORIZONTAL ) );
		
		new Label( composite, SWT.NONE ).setText( GROUP_DLG_GROUP_KEY_LABEL );
		
		Composite keyArea = new Composite( composite, SWT.NONE );
		keyArea.setLayoutData( new GridData( GridData.FILL_HORIZONTAL ) );
		keyArea.setLayout( UIUtil.createGridLayoutWithoutMargin( 2, false ) );
		keyChooser = new Combo( keyArea, SWT.DROP_DOWN );
		keyChooser.setLayoutData( new GridData( GridData.FILL_HORIZONTAL ) );
		keyChooser.addModifyListener( new ModifyListener( ) {
			public void modifyText( ModifyEvent e )
			{
				if ( !keyChooser.getText( ).trim( ).equals( "" ) ) 
					resetInterval( );
			}
		} );
		Button exprButton = new Button( keyArea, SWT.PUSH );
		exprButton.setText( "..." ); 
		exprButton.addSelectionListener( new SelectionAdapter( ) {
			public void widgetSelected( SelectionEvent event )
			{
				ExpressionBuilder expressionBuilder = new ExpressionBuilder( getKeyExpression( ) );
				expressionBuilder.setExpressionProvier( new ExpressionProvider( inputGroup ) );
				if ( expressionBuilder.open( ) == OK )
				{
					setKeyExpression( expressionBuilder.getResult( ).trim( ) );
				}
			}
		} );