实现一个简易的窗口系统，支持文字窗口，图标窗口，位图窗口及若干复合窗口。这个系统主要是用于学习及探寻窗口的一些知识。-Window implement a simple system to support the text window, the icon window, bitmap window and a number of composite windows. This system is mainly used for learning and exploring some of th