与HTML相似，Flex允许在MXML标签中通过CSS样式来设置组件的外观。到flex4.5后已经基本上支持了HTML中的所有CSS的应用方式，这里主要来列举下flex4.5中CSS选择器的使用方法。 CSS选择器可以包括，标签选择器、类别选择器、ID选择器、交集选择器、并集选择器、后代选择器、全局选择器、伪类等，这些样式应用都已经在flex得到支持。
1、标签选择器： 标签选择器是根据MXML文件中组件的类型来设置的，示例如下：
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<?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|TextInput{ color: #FF0000; } s|Button{ color: #FFFF00; } </fx:Style> <s:VGroup> <s:TextInput text="text input"/> <s:Button label="button"/> </s:VGroup></s:Application> |
2、类别选择器： 类别选择器是以一个点开头，后面加上组件中通过styleName设置的样式名来表示的类别选择器，示例如下：
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<?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"; .btn2{ color: #FF0000; } </fx:Style> <s:VGroup> <s:Button label="button1"/> <s:Button label="button2" styleName="btn2"/> </s:VGroup></s:Application> |
3、ID选择器： ID选择器是以#开头，后面加上组件中设置的ID名来表示的类别选择器，示例如下：
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<?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"; #btn1{ color: #FF0000; } .btn2{ color: #FF00FF; } </fx:Style> <s:VGroup> <s:Button id="btn1" label="button1"/> <s:Button label="button2" styleName="btn2"/> </s:VGroup></s:Application> |
4、交集选择器： 交集选择器由两个选择器直接连接构成，其结果是选中二者各自元素范围的交集，示例如下：
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<?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|Button#btn1{ color: #FF0000; } s|Button.btn2{ color: #FF00FF; } </fx:Style> <s:VGroup> <s:Button id="btn1" label="button1"/> <s:Button label="button2" styleName="btn2"/> <s:Button label="button3"/> </s:VGroup></s:Application> |
5、并集选择器： 并集选择器是多个选择器通过逗号连接而成的，并集选择器同时选中各个基本选择器所选择的范围，任何形式的选择器都可以，示例如下：
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<?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|Button#btn1,s|Button.btn2{ color: #FF0000; } </fx:Style> <s:VGroup> <s:Button id="btn1" label="button1"/> <s:Button label="button2" styleName="btn2"/> <s:Button label="button3"/> </s:VGroup></s:Application> |
6、后代选择器： 后代选择器也叫派生选择器，可以使用后代选择器给一个元素里的子元素定义样式，示例如下：
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<?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> |
7、全局选择器： 全局选择器global可以将样式应用到所有的组件，示例如下：
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<?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"; global{ color: #FF0000; } </fx:Style> <s:VGroup> <s:Label text="label"/> <s:TextInput text="text input"/> <s:Button label="button"/> </s:VGroup></s:Application> |
8：伪类： 伪类是用来设置组件在不同状态下的样式，示例如下：
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<?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|Button:up{ color: #FF0000; } s|Button:down{ color: #FF00FF; } s|Button:over{ color: #0000FF; } </fx:Style> <s:VGroup> <s:Button label="button"/> </s:VGroup></s:Application> |