程序功能描述：通过改变滑动条实现对话框中填充圆形的颜色，其中默认颜色为蓝色。程序中的圆形同样可以通过滑动条来改变它的大小。-descr iption of program features: sliders to achieve by changing the color of the dialog box filled circle, in which the default color is blue. The same procedure can be circular slider to