Not able to create new color item in colors.xml file

It's a weird bug. but here's a Workaround: Open the file in android studio and select all the text. now cut all the text and paste it in the same place. (or simply, go to the problematic file and press- 'ctrl+A' --> 'ctrl+x' --> 'ctrl+v') this does not change anything but apparently solves the errors.

Its a bug, and it happens for dimensions and possibly others. (Not just colours.) First time I saw it was the day I upgraded to AS 3.2.1.

But you may not need to clean, rebuild or invalidate caches. Try this:

(A) Cut and save (e.g. to NotePad) the flagged XML from the base folder and all qualified folders.
(B) Paste it back in, starting with the base folder

Update: 10Jan2019 [Dumb and dumber]

In fact, not even cutting and pasting is necessary. Suppose the following line is giving the problem...

<string name="edit">Edit</string>

Just change the tag to anything. e.g.

<xstring name="edit">Edit</string>

Then wait a second for removal to occur before changing it back

This error occures still in AS3.4C10... so it is not solved yet.

For me, the only remedy is to select "Invalidate Cache/Restart" from File menu.

RG

I solved the problem cleaning the project and build it again. If it doesn't work, invalidate caches and restart.

I'm using Android Studio 3.2

Invalidate Caches with File > Invalidate Caches / Restart... > Invalidate and Restart