Have you ever been working on a project, and then one day your syntax highlighting is gone? Your autocomplete is generating almost nothing useful? This trick saved me from bouts of madness.
- Quit Xcode
- Finder > Go (hold down the Option key while Go is selected – this will cause Library to pop up)
- Select Library
- Developer > Xcode > Derived Data
- Find the folder that has your app name & a jumble of characters behind it, i.e. “MyApp-dfwdfdfakjakjaka”
- Delete the folder.
- Launch Xcode and open your project
- It will be re-indexed and you’ll see a folder pop back into your Derived Data folder for the project.
- You should be good to go.