数据绑定是一个对象的数据与另一个对象绑定的过程.它需要一个源属性，一个目标属性和一个触发事件，指示何时将数据从源复制到目标.
Flex提供了三种方法来执行数据绑定，如下所示
MXML脚本中的曲线括号语法({})
< fx:binding> MXML中的标签
ActionScript中的BindingUtils
以下示例演示如何使用花括号指定源到目标的数据绑定.
<s:TextInput id = "txtInput1" />
<s:TextInput id = "txtInput2" text = "{txtInput1.text}" />以下示例演示如何使用
<fx:Binding source = "txtInput1.text" destination = "txtInput2.text" /> <s:TextInput id = "txtInput1" /> <s:TextInput id = "txtInput2" />
以下示例演示如何使用BindingUtils指定数据绑定来源到目的地.
<fx:Script>
<![CDATA[
import mx.binding.utils.BindingUtils;
import mx.events.FlexEvent;
protected function txtInput2_preinitializeHandler(event:FlexEvent):void {
BindingUtils.bindProperty(txtInput2,"text",txtInput1, "text");
}
]]>
</fx:Script>
<s:TextInput id = "txtInput1" />
<s:TextInput id = "txtInput2"
preinitialize = "txtInput2_preinitializeHandler(event)" />让我们按照下面给出的步骤查看Flex应用程序中的皮肤操作创建测试应用程序 :
| Step | 描述 |
|---|---|
| 1 | 在 com.it1352.client 包下创建一个名为 HelloWorld 的项目，如 Flex - 创建应用程序章节. |
| 2 | 修改 HelloWorld.mxml ，如下所述.保持其余文件不变. |
| 3 | 编译并运行应用程序以确保业务逻辑按照要求运行. |
以下是内容修改后的HelloWorld.mxml文件 src/com/it1352/client/HelloWorld.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
width = "100%" height = "100%" minWidth = "500" minHeight = "500">
<fx:Style source = "/com/IT屋/client/Style.css" />
<fx:Script>
<![CDATA[
import mx.binding.utils.BindingUtils;
import mx.events.FlexEvent;
protected function txtInput6_preinitializeHandler(event:FlexEvent):void {
BindingUtils.bindProperty(txtInput6,"text",txtInput5, "text");
}
]]>
</fx:Script>
<fx:Binding source = "txtInput3.text" destination = "txtInput4.text" />
<s:BorderContainer width = "500" height = "550" id = "mainContainer"
styleName = "container">
<s:VGroup width = "100%" height = "100%" gap = "50" horizontalAlign = "center"
verticalAlign = "middle">
<s:Label id = "lblHeader" text = "Data Binding Demonstration"
fontSize = "40" color = "0x777777" styleName = "heading" />
<s:Panel title = "Example #1 (Using Curly Braces,\{\})" width = "400"
height = "100" >
<s:layout>
<s:VerticalLayout paddingTop = "10" paddingLeft = "10" />
</s:layout>
<s:HGroup >
<s:Label text = "Type here: " width = "100" paddingTop = "6" />
<s:TextInput id = "txtInput1" />
</s:HGroup>
<s:HGroup >
<s:Label text = "Copied text: " width = "100" paddingTop = "6" />
<s:TextInput id = "txtInput2" text = "{txtInput1.text}" />
</s:HGroup>
</s:Panel>
<s:Panel title = "Example #2 (Using <fx:Binding>)" width = "400"
height = "100" >
<s:layout>
<s:VerticalLayout paddingTop = "10" paddingLeft = "10" />
</s:layout>
<s:HGroup >
<s:Label text = "Type here: " width = "100" paddingTop = "6" />
<s:TextInput id = "txtInput3" />
</s:HGroup>
<s:HGroup >
<s:Label text = "Copied text: " width = "100" paddingTop = "6" />
<s:Label id = "txtInput4" />
</s:HGroup>
</s:Panel>
<s:Panel title = "Example #3 (Using BindingUtils)" width = "400"
height = "100" >
<s:layout>
<s:VerticalLayout paddingTop = "10" paddingLeft = "10" />
</s:layout>
<s:HGroup >
<s:Label text = "Type here: " width = "100" paddingTop = "6" />
<s:TextInput id = "txtInput5" />
</s:HGroup>
<s:HGroup >
<s:Label text = "Copied text: " width = "100" paddingTop = "6" />
<s:TextInput enabled = "false" id = "txtInput6"
preinitialize = "txtInput6_preinitializeHandler(event)" />
</s:HGroup>
</s:Panel>
</s:VGroup>
</s:BorderContainer>
</s:Application>完成所有更改后，让我们按照正常模式编译并运行应用程序，就像我们在Flex - 创建应用程序章节.如果您的应用程序一切正常，它将产生以下结果:
