Setting the dropdown menu border thickness and border color on a ComboBox control in Flex

The following example shows how you can set the border color and border thickness on a Flex ComboBox control’s dropdown menu by setting the borderColor, borderThickness, and dropdownStyleName styles.

Full code after the jump.

View MXML

<?xml version="1.0" encoding="utf-8"?>
<!-- http://blog.flexexamples.com/2008/07/18/setting-the-dropdown-menu-border-thickness-and-border-color-on-a-combobox-control-in-flex/ -->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
        layout="vertical"
        verticalAlign="top"
        backgroundColor="white">

    <mx:Style>
        ComboBox {
            dropdownStyleName: myDropdownStyleNom;
        }

        .myDropdownStyleNom {
            borderColor: haloBlue;
            borderThickness: 5;
            fontWeight: normal;
        }
    </mx:Style>

    <mx:Array id="arr">
        <mx:Object label="One" />
        <mx:Object label="Two" />
        <mx:Object label="Three" />
        <mx:Object label="Four" />
        <mx:Object label="Five" />
        <mx:Object label="Six" />
        <mx:Object label="Seven" />
        <mx:Object label="Eight" />
        <mx:Object label="Nine" />
        <mx:Object label="Ten" />
    </mx:Array>

    <mx:ComboBox id="comboBox"
            dataProvider="{arr}" />

</mx:Application>

View source is enabled in the following example.

Due to popular demand, here is the “same” example in a more ActionScript friendly format:

View MXML

<?xml version="1.0" encoding="utf-8"?>
<!-- http://blog.flexexamples.com/2008/07/18/setting-the-dropdown-menu-border-thickness-and-border-color-on-a-combobox-control-in-flex/ -->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
        layout="vertical"
        verticalAlign="top"
        backgroundColor="white"
        initialize="init();">

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

            private var arr:Array;
            private var comboBox:ComboBox;

            private function init():void {
                arr = [];
                arr.push({label:"One"});
                arr.push({label:"Two"});
                arr.push({label:"Three"});
                arr.push({label:"Four"});
                arr.push({label:"Five"});
                arr.push({label:"Six"});
                arr.push({label:"Seven"});
                arr.push({label:"Eight"});
                arr.push({label:"Nine"});
                arr.push({label:"Ten"});

                var myDropdownStyleName:CSSStyleDeclaration;
                myDropdownStyleName = new CSSStyleDeclaration(".myDropdownStyleNom");
                myDropdownStyleName.setStyle("borderColor", "haloBlue");
                myDropdownStyleName.setStyle("borderThickness", 5);
                myDropdownStyleName.setStyle("fontWeight", "normal");

                comboBox = new ComboBox();
                comboBox.dataProvider = arr;
                comboBox.setStyle("dropdownStyleName", "myDropdownStyleNom");
                addChild(comboBox);
            }
        ]]>
    </mx:Script>

</mx:Application>