Xcode assistant editor won't show some of the code

First of all, I would like you to know that the class IS set to the correct file in each ViewController - I know that because it did work before, but then I got a "crash" in Xcode that blinked quickly without me being able to read it before it went off again.

MY PROBLEM IS:

I have a lot of ViewControllers in my Xcode, everything was working fine, I was making some more features to the ViewControllers.

Then I got the "crash" as mentioned above, and it would not show any of the files/classes related to their ViewController in assistant editor.

Assistant editor just said: No Assistant Results. Then I read that I could just show the files inside my XCode project and delete project.xcworkplace and xcuserdata. And I thought it worked at first, but it did not work on every viewcontroller unfortunately - only on some of them.

Now, I still have plenty of ViewControllers left to edit that aren't working, and I would hate if I had to recreate every single one.

Does anyone have a better solution to this? I really hope you do :-)

Make sure you set Automatic not Manual.