http://www.cnblogs.com/mandroid/archive/2011/06/15/2081093.html
http://www.cnblogs.com/youxilua/archive/2011/09/16/2178554.html
http://blog.csdn.net/zhangjg_blog/article/details/15505781
http://www.iteye.com/topic/304594#814127
原文：http://www.cnblogs.com/chuiyuan/p/4616585.html