——关于MXML

You use two languages to write Flex applications: MXML and ActionScript. MXML is an XML markup language that you use to lay out user interface components. You also use MXML to declaratively define nonvisual aspects of an application, such as access to data sources on the server and data bindings between user interface components and data sources on the server.
    您可以使用两种语言编写Flex应用程序：MXML和ActionScript。 MXML是一种可用于布置用户界面组件的XML标记语言，您还可以使用MXML来定义一个程序的非可视化方面，例如，访问服务器端的数据源，或者是将用户界面和服务器端的数据源绑定。

Like HTML, MXML provides tags that define user interfaces. MXML will seem very familiar if you have worked with HTML. However, MXML is more structured than HTML, and it provides a much richer tag set. For example, MXML includes tags for visual components such as data grids, trees, tab navigators, accordions, and menus, as well as nonvisual components that provide web service connections, data binding, and animation effects. You can also extend MXML with custom components that you reference as MXML tags.
    如同HTML一样，MXML提供了可以用来定义UI的标记。如果曾经使用过HTML，你会发现MXML和HTML很相似。然而，MXML比HTML更有条理，并提供更丰富的标记集合。例如，MXML中包含了数据网格，树，导航栏，折叠面板，菜单等可视组件标签，还提供了连接Web服务，数据绑定，以及动画效果等非可视组件。你还可以通过拓展MXML标记来实现你自己定制的MXML标记。

One of the biggest differences between MXML and HTML is that MXML-defined applications are compiled into SWF files and rendered by Adobe(R) Flash(R) Player or Adobe(R) AIR(TM), which provides a richer and more dynamic user interface than page-based HTML applications.
    与MXML和HTML的最大区别之一，是MXML定义的应用程序被编译成
SWF文件并且由Adobe(R)Flash(R)播放器或Adobe(R)的AIR(商标)（基于HTML的，提供了更丰富并且更加动态性UI的程序）来执行。

You can write an MXML application in a single file or in multiple files. MXML also supports custom components written in MXML and ActionScript files.
    你可以将一个MXML程序写成一个或者多个文件。MXML同时支持写在MXML和ActionScript文件中的自定义组件。