Specifications

77ADOBE FLEX 3

Building and Deploying Adobe Flex 3 Applications

Some applications must call the setStyle() method during the application or object instantiation. If this is the

case, call the

setStyle() method early in the instantiation phase. Early in the instantiation phase means setting

styles from the component or application’s

preinitialize event, instead of the initialize or

creationComplete event. By setting the styles as early as possible during initialization, you avoid unnecessary

style notification and lookup.

If you programmatically create a component and want to set styles on that component, call the

setStyle()

method before you attach it to the display list with a call to the

addChild() method, as the following example

shows:

<?xml version="1.0"?>

<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"

creationComplete="initApp(event)">

<mx:Script><![CDATA[

import mx.controls.Button;

public function initApp(e:Event):void {

var b:Button = new Button();

b.label="Click Me";

b.setStyle("color", 0x00CCFF);

panel1.addChild(b);

}

]]></mx:Script>

<mx:Panel id="panel1"/>

</mx:Application>

Setting global styles

Changing global styles (changing a CSS ruleset that is associated with a class or type selector) at run time is an

expensive operation. Any time you change a global style, Flash Player must perform the following actions:

• Traverse the entire application looking for instances of that control.

• Check all the control’s children if the style is inheriting.

• Redraw that control.

The following example globally changes the Button control’s color style property:

<?xml version="1.0"?>

<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"

creationComplete="initApp(event)">

<mx:Script><![CDATA[

public function initApp(e:Event):void {