Unknown class swift

Question

I have for months tried to find what causes the following in Xcode. I have deleted the temporary files, searched through the MainStoryboard file - no success.. I dont know how to fix it.. Source code of project is on GitHub (https://github.com/rsyncOSX/Version3.x).

One problem solved - the second issue is still there. Have searched through Main.storyboard file, cannot spot the problem. The ViewController IDed by 3xI-3C-guU is valid. I am also finding reference to fs3-Ij-mBm searching in Main.storyboard.

2016-12-19 09:06:43.068961 RsyncOSX[10461:604908] Unknown class _TtC8RsyncOSX21TabViewControllerMain in Interface Builder file at path /Volumes/Home/thomas/Library/Developer/Xcode/DerivedData/RsyncOSX-budzkonsqjvzovfxbfnmopllerwh/Build/Products/Debug/RsyncOSX.app/Contents/Resources/Base.lproj/Main.storyboardc/NSWindowController-abu-zT-Ht4.nib.

2016-12-19 09:06:43.270247 RsyncOSX[10461:604908] Unknown class View in Interface Builder file at path /Volumes/Home/thomas/Library/Developer/Xcode/DerivedData/RsyncOSX-budzkonsqjvzovfxbfnmopllerwh/Build/Products/Debug/RsyncOSX.app/Contents/Resources/Base.lproj/Main.storyboardc/3xI-3C-guU-view-fs3-Ij-mBm.nib.

Answer 1

This problem can occur when you change a classname of a UIViewController even though a storyboard does still have the old classname. You can fix this by finding out which storyboard it is that is causing this problem (try the search function in Xcode, it will tell you that you can find classname in file example.storyboard) and update the name accordingly.