swift code completion doesn't work

Question

I don't know what's wrong with my xcode. My project could run on my iphone properly (so I guess there is nothing wrong with my project). But in the Xcode editor, I couldn't "jump" to function or variables definition. it shows

this could be fixed by just restarting Xcode.However, after about a few minutes, it doesn't work again...

I already check Xcode 6 Swift code completion not working But no luck..

my swift version is 1.2, and Xcode version is Version 6.4 (6E35b)

any one help?

Answer 1

Unfortunately the Swift support in XCode is still very buggy. It gets better with every release, but it's far away from perfect.

For me, the only thing that seems to help is to delete DerivedData and restart Xcode.