Setting a background image on a Halo Button control in Flex 4

The following example shows how you can set a background image fill on a Halo Button control (with default Spark skin) in Flex 4 by creating a custom Button skin and setting the skin style.

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/2009/07/10/setting-a-background-image-on-a-halo-button-control-in-flex-4/ -->
<s:Application name="Halo_Button_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">
 
    <mx:Button id="btn"
            label="Halo Button"
            skin="skins.CustomButtonSkin"
            horizontalCenter="0" verticalCenter="0" />
 
</s:Application>

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

<?xml version="1.0" encoding="utf-8"?>
<!-- http://blog.flexexamples.com/2009/07/10/setting-a-background-image-on-a-halo-button-control-in-flex-4/ -->
<local:SparkSkinForHalo name="CustomButtonSkin"
        xmlns:fx="http://ns.adobe.com/mxml/2009"
        xmlns:s="library://ns.adobe.com/flex/spark" 
        xmlns:local="mx.skins.spark.*"
        minWidth="21" minHeight="19" 
        alpha.disabled="0.5">
    <!-- states -->
    <local:states>
        <s:State name="up" />
        <s:State name="over" stateGroups="overStates" />
        <s:State name="down" stateGroups="downStates" />
        <s:State name="disabled" stateGroups="disabledStates" />
        <s:State name="selectedUp" stateGroups="selectedStates, selectedUpStates" />
        <s:State name="selectedOver" stateGroups="overStates, selectedStates" />
        <s:State name="selectedDown" stateGroups="downStates, selectedStates" />
        <s:State name="selectedDisabled" stateGroups="selectedUpStates, disabledStates, selectedStates" />
    </local:states>
 
    <fx:Script>
        /* Define the border items.*/
        static private const borderItem:Array = ["borderEntry1", "borderEntry2"];
        override protected function get borderItems():Array {
            return borderItem;
        }
    </fx:Script>
 
    <!-- layer 1: shadow -->
    <s:Rect left="-1" right="-1" top="-1" bottom="-1"
            radiusX="2" radiusY="2">
        <s:fill>
            <s:LinearGradient rotation="90">
                    <s:GradientEntry color="0x000000" 
                            color.downStates="0xFFFFFF"
                            alpha="0.01"
                            alpha.downStates="0" />
                    <s:GradientEntry color="0x000000" 
                            color.downStates="0xFFFFFF" 
                            alpha="0.07"
                            alpha.downStates="0.5" />
            </s:LinearGradient>
        </s:fill>
    </s:Rect>
 
    <!-- layer 2: fill -->
    <s:Rect left="1" right="1" top="1" bottom="1"
            radiusX="2" radiusY="2"
            alpha="0.6">
        <s:fill>
            <s:BitmapFill source="@Embed('assets/pattern_149.gif')" />
        </s:fill>
    </s:Rect>
 
    <!-- layer 3: fill lowlight -->
    <s:Rect left="1" right="1" bottom="1" height="9"
            radiusX="2" radiusY="2">
        <s:fill>
            <s:LinearGradient rotation="90">
                <s:GradientEntry color="0x000000" alpha="0.0099" />
                <s:GradientEntry color="0x000000" alpha="0.0627" />
            </s:LinearGradient>
        </s:fill>
    </s:Rect>
 
    <!-- layer 4: fill highlight -->
    <s:Rect left="1" right="1" top="1" height="9"
            radiusX="2" radiusY="2">
        <s:fill>
            <s:SolidColor color="0xFFFFFF" 
                        alpha="0.33" 
                        alpha.selectedUpStates="0.22"
                        alpha.overStates="0.22" 
                        alpha.downStates="0.12" />
        </s:fill>
    </s:Rect>
 
    <!-- layer 5: highlight stroke (all states except down) -->
    <s:Rect left="1" right="1" top="1" bottom="1"
            radiusX="2" radiusY="2"
            excludeFrom="downStates">
        <s:stroke>
            <s:LinearGradientStroke rotation="90" weight="1">
                <s:GradientEntry color="0xFFFFFF"
                        alpha.overStates="0.22"
                        alpha.selectedUpStates="0.33" />
                <s:GradientEntry color="0xD8D8D8"
                        alpha.overStates="0.22"
                        alpha.selectedUpStates="0.33" />
            </s:LinearGradientStroke>
        </s:stroke>
    </s:Rect>
 
    <!-- layer 6: highlight stroke (down state only) -->
    <s:Rect left="1" top="1" bottom="1" width="1"
            includeIn="downStates, selectedUpStates, selectedOver">
        <s:fill>
            <s:SolidColor color="0x000000" alpha="0.07" />
        </s:fill>
    </s:Rect>
    <s:Rect right="1" top="1" bottom="1" width="1"
            includeIn="downStates, selectedUpStates, selectedOver">
        <s:fill>
            <s:SolidColor color="0x000000" alpha="0.07" />
        </s:fill>
    </s:Rect>
    <s:Rect left="2" top="1" right="2" height="1"
            includeIn="downStates, selectedUpStates, selectedOver">
        <s:fill>
            <s:SolidColor color="0x000000" alpha="0.25" />
        </s:fill>
    </s:Rect>
    <s:Rect left="1" top="2" right="1" height="1"
            includeIn="downStates, selectedUpStates, selectedOver">
        <s:fill>
            <s:SolidColor color="0x000000" alpha="0.09" />
        </s:fill>
    </s:Rect>
 
    <!-- layer 7: border - put on top of the fill so it doesn't disappear when scale is less than 1 -->
    <s:Rect left="0" right="0" top="0" bottom="0"
            width="69" height="20"
            radiusX="2" radiusY="2">
        <s:stroke>
            <s:LinearGradientStroke rotation="90" weight="1">
                <s:GradientEntry id="borderEntry1" 
                        alpha="0.5625"
                        alpha.down="0.6375"
                        alpha.selectedStates="0.6375" />
                <s:GradientEntry id="borderEntry2" 
                        alpha="0.75" 
                        alpha.down="0.85"
                        alpha.selectedStates="0.85" />
            </s:LinearGradientStroke>
        </s:stroke>
    </s:Rect>
 
</local:SparkSkinForHalo>

[HaloSparkSkins]

View source is enabled in the following example.

[Squidfingers]

[GoogleAdsWide]

You can also set the skin 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/2009/07/10/setting-a-background-image-on-a-halo-button-control-in-flex-4/ -->
<s:Application name="Halo_Button_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|Button {
            skin: ClassReference("skins.CustomButtonSkin");
        }
    </fx:Style>
 
    <mx:Button id="btn"
            label="Halo Button"
            horizontalCenter="0" verticalCenter="0" />
 
</s:Application>

Or, you can set the skin style using ActionScript, as seen in the following example:

<?xml version="1.0" encoding="utf-8"?>
<!-- http://blog.flexexamples.com/2009/07/10/setting-a-background-image-on-a-halo-button-control-in-flex-4/ -->
<s:Application name="Halo_Button_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:Script>
        <![CDATA[
            import skins.CustomButtonSkin;
 
            protected function btn2_click(evt:MouseEvent):void {
                btn.setStyle("skin", CustomButtonSkin);
            }
        ]]>
    </fx:Script>
 
    <mx:ApplicationControlBar width="100%" cornerRadius="0">
        <s:Button id="btn2"
                label="Set Button skin"
                click="btn2_click(event);" />
    </mx:ApplicationControlBar>
 
    <mx:Button id="btn"
            label="Halo Button"
            horizontalCenter="0" verticalCenter="0" />
 
</s:Application>

Finally, you can set the skin style globally using the StyleManager class, as seen in the following example:

<?xml version="1.0" encoding="utf-8"?>
<!-- http://blog.flexexamples.com/2009/07/10/setting-a-background-image-on-a-halo-button-control-in-flex-4/ -->
<s:Application name="Halo_Button_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.CustomButtonSkin;
 
            private function init():void {
                var buttonStyles:CSSStyleDeclaration = StyleManager.getStyleDeclaration("mx.controls.Button");
                buttonStyles.setStyle("skin", CustomButtonSkin);
            }
        ]]>
    </fx:Script>
 
    <mx:Button id="btn"
            label="Halo Button"
            horizontalCenter="0" verticalCenter="0" />
 
</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.

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