srgp

代码说明：

  简单的图形学SRGP教学包运用实现。 A．实现一个下拉菜单软件包，其高层设计见2.2.6节、2.3.1节、2.3.3节中的代码段。软件包通过从输入文件读入字符串来初始化菜单条和菜单体。程序可以通过关闭菜单条使标题消失，也可以激活一个菜单（以各菜单标题在菜单条上的水平位置作为参数）来使菜单出现。 (Simple graphics SRGP realize the use of teaching packages. A. The realization of a drop-down menu package, and its high-level design, see section 2.2.6, section 2.3.1, section 2.3.3 of the code segment. Package from the input file is read into the string to initialize the menu and menu body. Procedures can be closed so that the title menu disappear, but also can activate a menu (in the menu heading in the menu bar on the horizontal position as a parameter) to make the menu appear.)