In this section, you will learn how to build ext JS extensions.

在这一小节，您将学习如何构建Ext JS扩展。

youdao

An extension for ext JS is a derived class or a subclass, which is designed to allow the inclusion of additional features to existing ext JS classes.

Ext JS的扩展是从类或者子类衍生出来的，为支持现有Ext JS类包含附加特性而设计的。

youdao

Thankfully, ext JS includes a powerful class and component ecosystem that makes it easy to extend existing features or build new components entirely.

谢天谢地，Ext JS包含一个功能强大的类和组件生态系统，可以轻松地扩展现有特性或者完全构建新组件。

youdao