一个通过继承ViewGroup，应用Scroller实现的手动拖拽滚屏及自动滚屏的自定义UI控件，可以让初学者很容易地看明白如何制作自定义滚屏效果-1 through inheritance ViewGroup, application Scroller Scroll to achieve manual and automatic scrolling drag custom UI controls, so that beginners can easily understand how to c