Displaying icons in a Flex PopUpButton control

<?xml version="1.0"?>
<!-- http://blog.flexexamples.com/2008/01/24/displaying-icons-in-a-flex-popupbutton-control/ -->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
        layout="horizontal"
        verticalAlign="top"
        backgroundColor="white">

    <mx:Script>
        <![CDATA[
            import mx.controls.Menu;

            [Bindable]
            private var menu:Menu;

            private function initMenu():void {
                menu = new Menu();
                menu.dataProvider = arr;
            }
        ]]>
    </mx:Script>

    <mx:Style>
        PopUpButton {
            popUpStyleName: myCustomPopUpStyleName;
        }

        .myCustomPopUpStyleName {
           fontWeight: normal;
           textAlign: left;
        }
    </mx:Style>

    <mx:Array id="arr">
        <mx:Object label="Alert" />
        <mx:Object label="Button"
                icon="@Embed('assets/Button.png')" />
        <mx:Object label="ButtonBar"
                icon="@Embed('assets/ButtonBar.png')" />
        <mx:Object label="CheckBox"
                icon="@Embed('assets/CheckBox.png')" />
        <mx:Object label="ColorPicker"
                icon="@Embed('assets/ColorPicker.png')" />
    </mx:Array>

    <mx:PopUpButton id="popUpButton"
            label="Select a control..."
            popUp="{menu}"
            preinitialize="initMenu();"
            creationComplete="popUpButton.open();" />

</mx:Application>