Android - View Alpha值
本文地址: http://blog.csdn.net/caroline_wendy
Alpha值主要控制图像的透明度(0-1)，0代表透明，1代表不透明。
Sets the opacity of the view. This is a value from 0 to 1, where 0 means the view is completely transparent and 1 means the view is completely opaque.
Android - View Alpha值
原文：http://blog.csdn.net/caroline_wendy/article/details/40624941
