在github上下载安卓代码在本机运行的时候由于环境不一样，运行时可能会报出这样的错误：
No Android facet found in the module
在IDEA/Android Stdio下可以可以这样解决：
Add an android facet to your module by following below steps.
1) Go To File Menu -> Project Structure, or press (Ctrl+Alt+Shift+S) shortcut to open “Project Structure”.
2) Select “Facets” which is under the “Project Settings” tab. (First column)
3) Click on “+” button which is at the top of the Second Column to add new facets.
4) Select “Android” facet from that “Add “menu which will prompt another dialog box to select a module. (Select a module to which you want to apply this facet).
5) Select your module and that’s it. :)