一个简单的说明应用框架生成的应用程序，主要用于说明应用程序的应用类、主框架窗口类以及视类、文档类在应用程序中的构成。-Illustrate the application of a simple fr a mework to generate applications, mainly used to describe the application' s classes, as well as the main fr a me window class class, document cl