Flex中的CSS： （3）CSS会被编译器转换为什么样的AS代码--派生：

解说：

s|HGroup s|TextInput?? 为HGroup中定义的TextInput设置CSS样式。

这是一种依据元素在其位置的上下文关系来定义样式的方式。

这种形式的定义称为：派生

test1.mxml

<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
			   xmlns:s="library://ns.adobe.com/flex/spark"
			   xmlns:mx="library://ns.adobe.com/flex/mx" minWidth="955" minHeight="600">
	<fx:Style>
		@namespace s "library://ns.adobe.com/flex/spark";
		@namespace mx "library://ns.adobe.com/flex/mx";
		s|HGroup s|TextInput{
			color: #FF0000;
		}
	</fx:Style>
	<s:VGroup>
		<s:HGroup verticalAlign="middle">
			<s:Label text="Text Input 1"/>
			<s:TextInput text="sample"/>
		</s:HGroup>
		<s:TextInput text="sample"/>
	</s:VGroup>
</s:Application>

执行结果：

编译器自动生成的代码：

        var conditions:Array;
        var condition:CSSCondition;
        var selector:CSSSelector;
        selector = null;
        conditions = null;
        conditions = null;
        selector = new CSSSelector("spark.components.HGroup",conditions,selector);
        conditions = null;
        selector = new CSSSelector("spark.components.TextInput",selector);
        // spark.components.HGroup spark.components.TextInput
        style = styleManager.getStyleDeclaration("spark.components.HGroup spark.components.TextInput");
        if (!style)
        {
            style = new CSSStyleDeclaration(selector,styleManager);
        }

        if (style.factory == null)
        {
            style.factory = function():void
            {
                this.color = 0xff0000;
            };
        }

可见，

对于派生，编译器将其视为一个整体进行AS转换。