Xcode 9 code completion and highlighting not working

Question

I have seen many threads about this online, but not for Xcode 9. For some reason code completion and syntax highlighting is no longer working. Last week it was fine.

Using the GM build.

Anyone have this issue or know how to resolve it? A restart of Xcode and my computer did not help.

fwiw I'm seeing the same thing. Don't remember this from the beta either. Hopefully fixed in next version. — ryan gordon, Sep 28 '17 at 18:36
Happens for me on just one project, and syntax coloring is also incomplete. When I open any other project it works fine. — gpdawson, Oct 03 '17 at 04:10

score 34 · Accepted Answer · answered Oct 03 '17 at 04:33

34

In Finder I navigated to user->Library->Developer->Xcode->DerivedData and deleted the subfolder of the project in question. After next build of the project the syntax highlighting and code completion returned.

answered Oct 03 '17 at 04:33

gpdawson

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Derived data strikes again! – Rob MacEachern Jan 04 '18 at 00:07
1

What an absolute joke that this is still routinely necessary after years. They might as well have a dedicated button for it next to the Build and Run button. – TylerJames Mar 11 '20 at 16:35

score 7 · Answer 2 · answered Mar 12 '18 at 05:42

7

In my situation, there are a few of .swift files not working. I've overcome by removing these files from project and re-adding them back.

answered Mar 12 '18 at 05:42

azun

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I have to remove folder group and add them again. – geek1706 Oct 11 '18 at 13:46
Same here. This happened for me because i renamed a file. Deleting the reference and then re-adding ti worked for me. – Jess McKenzie Jan 11 '20 at 11:16

score 5 · Answer 3 · answered Oct 19 '17 at 00:31

5

Quitting Xcode then reopening it works for me.

answered Oct 19 '17 at 00:31

C. Bess

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score 0 · Answer 4 · answered Sep 22 '19 at 19:13

0

To make it work again, I have to restart the macOS System. I'm using Xcode 11.0 (11A420a), at the same time, Xcode 10 works OK. So I think there is some process does not work, which should work for code coloring.

answered Sep 22 '19 at 19:13

DawnSong

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score 0 · Answer 5 · answered Jun 10 '20 at 05:41

0

For me, code completion/highlighting not working due to the missing file in the Compile Sources under Build Phases. I added that file and it works.

Hope this helps anyone.

answered Jun 10 '20 at 05:41

iGW

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Chandan · Answer 6 · 2017-11-10T15:53:20.220

-2

I have observed the same problem while writing in swift on xcode 9.0, Seems it is fixed in 9.1 i am using 9.1 which is fine, please update xcode to 9.1 or newer.

edited Nov 10 '17 at 15:53

answered Nov 06 '17 at 15:43

Chandan

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I don't think so, I'm using Xcode 9.1 and issue sometimes turn back – Luca Davanzo Nov 20 '17 at 10:49

Xcode 9 code completion and highlighting not working

6 Answers6

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