实现了一个简单的绘工具，该绘图工具具有打开，关闭，保存，另存文件的功能；它能够对直线，矩形等几种图元进行绘制和操作。-Achieve a simple drawing tools, the mapping tool to open, close, save, save files it can on a straight line, rectangle, etc. to carry out several pixel mapping and operation.