Android Studio Rendering Problems : The following classes could not be found


I just update Android Studio, and when I restarted it, the preview window rendering failed, and I was told that

The following classes could not be found:

If someone can tell me what can I do to fix this rendering problem? Thank you.

Best Answer

You have to do two things:

  • be sure to have imported right appcompat-v7 library in your project structure -> dependencies
  • change the theme in the preview window to not an AppCompat theme. Try with Holo.light or Holo.dark for example.