Design not working in Android Studio. How to fix?

Question

Android

Before everything worked fine and when creating a new project everything works. But I have an old project to which I have not returned for about a month. And now Design doesn't work in Android Studio. Maybe someone knows how to fix it.

Answer 1

It is necessary to correct the errors that the studio writes - they are at the bottom, related to the markup of the activity.

Answer 2

The studio should highlight your errors in the markup of the activity, often the essence of the problem is clear in the text of the error, you can remove these deadlines - temporarily, in order to make sure that the design mode works, and you can also try to create any empty activity.