Creating a repeating image header background on a Halo Accordion container in Flex 4

The following example shows how you can create a custom, repeating image header background on a Halo Accordion container (with default Spark skin) in Flex 4 by setting the headerStyleName and skin styles.

Full code after the jump.

The following example(s) require Flash Player 10 and the Adobe Flex 4 SDK. To download the Adobe Flash Builder 4 trial, see www.adobe.com/products/flex/. To download the latest nightly build of the Flex 4 SDK, see opensource.adobe.com/wiki/display/flexsdk/Download+Flex+4.

For more information on getting started with Flex 4 and Flash Builder 4, see the official Adobe Flex Team blog.

<?xml version="1.0" encoding="utf-8"?>
<!-- http://blog.flexexamples.com/2009/07/03/creating-a-repeating-image-header-background-on-a-halo-accordion-container-in-flex-4/ -->
<s:Application name="Halo_Accordion_headerStyleName_skin_test"
        xmlns:fx="http://ns.adobe.com/mxml/2009"
        xmlns:s="library://ns.adobe.com/flex/spark"
        xmlns:mx="library://ns.adobe.com/flex/halo">
 
    <fx:Style>
        @namespace s "library://ns.adobe.com/flex/spark";
        @namespace mx "library://ns.adobe.com/flex/halo";
 
        .accordionHeaderStyles {
            skin: ClassReference("skins.CustomAccordionHeaderSkin");
        }
    </fx:Style>
 
    <mx:Accordion id="accordion"
            headerStyleName="accordionHeaderStyles"
            width="80%" height="80%"
            horizontalCenter="0" verticalCenter="0">
        <mx:VBox label="Red" />
        <mx:VBox label="Orange" />
        <mx:VBox label="Yellow" />
        <mx:VBox label="Green" />
        <mx:VBox label="Blue" />
    </mx:Accordion>
 
</s:Application>

And the custom skin class, skins/CustomAccordionHeaderSkin.mxml, is as follows:

<?xml version="1.0" encoding="utf-8"?>
<!-- http://blog.flexexamples.com/2009/07/03/creating-a-repeating-image-header-background-on-a-halo-accordion-container-in-flex-4/ -->
<s:SparkSkin name="CustomAccordionHeaderSkin"
        xmlns:fx="http://ns.adobe.com/mxml/2009"
        xmlns:s="library://ns.adobe.com/flex/spark"
        minWidth="21" minHeight="21"
        alpha.disabled="0.5">
    <!-- states -->
    <s:states>
        <s:State name="up" />
        <s:State name="over" />
        <s:State name="down" />
        <s:State name="disabled" />
        <s:State name="selectedUp" />
        <s:State name="selectedOver" />
        <s:State name="selectedDown" />
        <s:State name="selectedDisabled" />
    </s:states>
 
    <!-- layer 1: fill -->
    <s:Rect left="1" right="1" top="1" bottom="1" alpha="0.6">
        <s:fill>
            <s:BitmapFill source="@Embed('assets/pattern_147.gif')" />
        </s:fill>
    </s:Rect>
 
    <!-- layer 2: fill lowlight -->
    <s:Rect left="1" right="1" bottom="1" height="9">
        <s:fill>
            <s:LinearGradient rotation="90">
                <s:GradientEntry color="black" alpha="0.0099" />
                <s:GradientEntry color="black" alpha="0.0627" />
            </s:LinearGradient>
        </s:fill>
    </s:Rect>
 
    <!-- layer 3: fill highlight -->
    <s:Rect left="1" right="1" top="1" height="9">
        <s:fill>
            <s:SolidColor color="white"
                    alpha="0.33"
                    alpha.over="0.22"
                    alpha.down="0.12" />
        </s:fill>
    </s:Rect>
 
    <!-- layer 4: highlight stroke (all states except down) -->
    <s:Rect left="1" right="1" top="1" bottom="1" excludeFrom="down">
        <s:stroke>
            <s:LinearGradientStroke rotation="90">
                <s:GradientEntry color="white" alpha.over="0.22" />
                <s:GradientEntry color="0xD8D8D8" alpha.over="0.22" />
            </s:LinearGradientStroke>
        </s:stroke>
    </s:Rect>
 
    <!-- layer 5: highlight stroke (down state only) -->
    <s:Rect left="1" top="1" bottom="1" width="1" includeIn="down">
        <s:fill>
            <s:SolidColor color="black" alpha="0.07" />
        </s:fill>
    </s:Rect>
    <s:Rect right="1" top="1" bottom="1" width="1" includeIn="down">
        <s:fill>
            <s:SolidColor color="black" alpha="0.07" />
        </s:fill>
    </s:Rect>
    <s:Rect left="1" top="1" right="1" height="1" includeIn="down">
        <s:fill>
            <s:SolidColor color="black" alpha="0.25" />
        </s:fill>
    </s:Rect>
    <s:Rect left="1" top="2" right="1" height="1" includeIn="down">
        <s:fill>
            <s:SolidColor color="black" alpha="0.09" />
        </s:fill>
    </s:Rect>
 
    <!-- layer 6: border -->
    <s:Rect left="0" right="0" top="0" bottom="0" width="69" height="20">
        <s:stroke>
            <s:SolidColorStroke color="0x696969"
                    alpha="1"
                    alpha.over="1"
                    alpha.down="1" />
        </s:stroke>
    </s:Rect>
 
</s:SparkSkin>

[HaloSparkSkins]

View source is enabled in the following example.

[Squidfingers]

[GoogleAdsWide]

You can also set the headerStyleName style in an external .CSS file or <Style/> block, as seen in the following example:

<?xml version="1.0" encoding="utf-8"?>
<!-- http://blog.flexexamples.com/2009/07/03/creating-a-repeating-image-header-background-on-a-halo-accordion-container-in-flex-4/ -->
<s:Application name="Halo_Accordion_headerStyleName_skin_test"
        xmlns:fx="http://ns.adobe.com/mxml/2009"
        xmlns:s="library://ns.adobe.com/flex/spark"
        xmlns:mx="library://ns.adobe.com/flex/halo">
 
    <fx:Style>
        @namespace s "library://ns.adobe.com/flex/spark";
        @namespace mx "library://ns.adobe.com/flex/halo";
 
        mx|Accordion {
            headerStyleName: accordionHeaderStyles;
        }
        .accordionHeaderStyles {
            skin: ClassReference("skins.CustomAccordionHeaderSkin");
        }
    </fx:Style>
 
    <mx:Accordion id="accordion"
            width="80%" height="80%"
            horizontalCenter="0" verticalCenter="0">
        <mx:VBox label="Red" />
        <mx:VBox label="Orange" />
        <mx:VBox label="Yellow" />
        <mx:VBox label="Green" />
        <mx:VBox label="Blue" />
    </mx:Accordion>
 
</s:Application>

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

<?xml version="1.0" encoding="utf-8"?>
<!-- http://blog.flexexamples.com/2009/07/03/creating-a-repeating-image-header-background-on-a-halo-accordion-container-in-flex-4/ -->
<s:Application name="Halo_Accordion_headerStyleName_skin_test"
        xmlns:fx="http://ns.adobe.com/mxml/2009"
        xmlns:s="library://ns.adobe.com/flex/spark"
        xmlns:mx="library://ns.adobe.com/flex/halo"
        initialize="init();">
 
    <fx:Script>
        <![CDATA[
            import skins.CustomAccordionHeaderSkin;
            import mx.containers.Accordion;
            import mx.containers.VBox;
 
            private var accordion:Accordion;
            private var vBox1:VBox;
            private var vBox2:VBox;
            private var vBox3:VBox;
            private var vBox4:VBox;
            private var vBox5:VBox;
            private var accordionHeaderStyles:CSSStyleDeclaration;
 
            private function init():void {
                accordionHeaderStyles = new CSSStyleDeclaration();
                accordionHeaderStyles.setStyle("skin", CustomAccordionHeaderSkin);
 
                vBox1 = new VBox();
                vBox1.label = "Red";
 
                vBox2 = new VBox();
                vBox2.label = "Orange";
 
                vBox3 = new VBox();
                vBox3.label = "Yellow";
 
                vBox4 = new VBox();
                vBox4.label = "Green";
 
                vBox5 = new VBox();
                vBox5.label = "Blue";
 
                accordion = new Accordion();
                accordion.percentWidth = 80;
                accordion.percentHeight = 80;
                accordion.horizontalCenter = 0;
                accordion.verticalCenter = 0;
                accordion.setStyle("headerStyleName", accordionHeaderStyles);
                accordion.addElement(vBox1);
                accordion.addElement(vBox2);
                accordion.addElement(vBox3);
                accordion.addElement(vBox4);
                accordion.addElement(vBox5);
                addElement(accordion);
            }
        ]]>
    </fx:Script>
 
</s:Application>

This entry is based on a beta version of the Flex 4 SDK and therefore is very likely to change as development of the Flex SDK continues. The API can (and will) change causing examples to possibly not compile in newer versions of the Flex 4 SDK.