Development Flex

    xmlns:mx="http://www.adobe.com/2006/mxml" 
     
    xmlns:s="library://ns.adobe.com/flex/spark">
    
    
        
            import spark.utils.TextFlowUtil;
            
            [Bindable]
            public var txt:String = "
" +
                "" +
                "

this is a test" + "bold" +
                "

";
      
    

    
                            columnCount="4"
                    fontFamily="Helvetica"
                    textFlow="{TextFlowUtil.importFromString(txt)}"
                    />