android studio出现rendering problem

刚刚装的AS，建了工程后出不来手机视图，API也只有6.0，急死了

http://blog.sina.com.cn/s/blog_4a628f030102vghb.html

http://stackoverflow.com/questions/18195807/android-studio-rendering-problems

http://blog.csdn.net/asmcvc/article/details/30225365