83、android的消息处理机制(图+源码分析)——Looper,Handler,Message
转载:http://www.cnblogs.com/codingmyworld/archive/2011/09/12/2174255.html
https://my.oschina.net/u/1391648/blog/282892
http://www.jianshu.com/p/9e4d1fab0f36
理解ThreadLocal http://blog.csdn.net/qjyong/article/details/2158097