anchor.diff:  * http://www.broadview.com.cn/book/2549[Android系统源代码情景分析^]
   |===
   
  +== 底层
   [cols=",a"]
  -== 底层
   |===
   |条目 |资源
   
  
positive.code: |
  |===
  
  [cols=",a"]
  == 应用
  |===
  |条目 |资源
  
  
negative.code: :toc:
  :toc-title: 目录
  
  == 语言
  [cols=",a,a"]
  |===
  |条目 |入门 |进阶
   
  