知乎效果 V2.0 新增第一次打开的新手引导效果：如果需要研究的请看下面链接： https://github.com/xiangzhihong/MaterialIntroView-master 开源协议 Copyright (C) 2016 This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; e