Why is Android Studio reporting "URI is not registered"? [closed]

So I've given Android Studio a try, because I really like Resharper and noticed that the IDE had some of their functionality built into it. Having now created a default new project, I added a new layout file and wanted to change the existing default 'hello world' example layout, and I got an "URI is not registered" error on the following lines:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
 xmlns:tools="http://schemas.android.com/tools"

I've done nothing else to the default generated project yet. I've come across another question that seems to be related (Intellij Android project schema URI not registered?), but just ignoring something feels odd to me. I actually tried it, but that causes RelativeLayout (and probably all other Android related stuff) to be not recognised any more (error message: "Cannot find the declaration of element 'RelativeLayout'").

Any ideas on how to solve this problem?

Solution 1:

You are having this issue because you are at the wrong destination! The correct directory for the Layout resource file has to be under "res-layout" not "res-all-layout"

Solution 2:

For me this was because I was using a debug and release build variant. I added the new folders src/debug/res/layout/some_layout.xml file manually, and it didn't recognize the URI. I switched the build variant to release, and then back to debug. This caused Android Studio to reload something, and the error went away.

EDIT: Also check that you have the correct filename. I had this issue again by adding a debug AndroidManifest.xml, but mistakenly named it AndroidManifest.xml.xml.