Missing styles. Is the correct theme chosen for this layout?

Question

Missing styles. Is the correct theme chosen for this layout? Use the Theme combo box above the layout to choose a different layout, or fix the theme style ref

Answer 1

What I usually do is the following: a Gradle Clean, Rebuild and Sync all my Gradle files. After that I restart Android Studio, and I go to:

Select Theme -> Project Themes -> AppTheme