Bug 312859 The list of operator for Chart filter does not provide 30 visible items
chart/org.eclipse.birt.chart.reportitem.ui/src/org/eclipse/birt/chart/reportitem/ui/dialogs/ChartCubeFilterConditionBuilder.java
{
			initValue = ( (Text) control ).getText( );
		}
		else if ( control instanceof Combo )
		{
			initValue = ( (Combo) control ).getText( );
		}
		ExpressionBuilder expressionBuilder = new ExpressionBuilder( getShell( ),
				initValue );
		if ( designHandle != null )
		{
			if ( expressionProvider == null )
			{
				ExpressionProvider exprProvider = new ChartCubeFilterExpressionProvider( designHandle,
						fExprMap.values( ).toArray( new String[]{} ) );
				expressionBuilder.setExpressionProvider( exprProvider );
			}
			else
				expressionBuilder.setExpressionProvider( expressionProvider );
		}
		if ( expressionBuilder.open( ) == OK )
		{
			String result = DEUtil.resolveNull( expressionBuilder.getResult( ) );
			if ( control instanceof Text )
			{
				( (Text) control ).setText( result );
			}
			else if ( control instanceof Combo )
			{
				( (Combo) control ).setText( result );