Replace (or "Override") String in Android Library Project

I have the same arrangement and this works for me as expected.

The library has layout/class with this reference to a string resource:

<TextView android:id="@+id/studentSinceLabel">

The library provides a default value in its strings.xml:

<string name="studentSinceLabel">Student Since</string>

The main app has this value in its strings.xml:

<string name="studentSinceLabel">Client Since</string>

When I give a value for this resource in the main apps strings.xml, I see "Client Since" when the app runs, when I delete it from the main apps strings.xml, I see the value from the library, "Student Since".

Seems this is expected behaviour based on my reading here: http://developer.android.com/tools/sdk/eclipse-adt.html

Relevant quote from the link above:

In the cases where a resource ID is defined in both the application and the library, the tools ensure that the resource declared in the application gets priority and that the resource in the library project is not compiled into the application .apk. This gives your application the flexibility to either use or redefines any resource behaviours or values that are defined in any library.

Just had this error, here is what happened in my case :

If you are using multiple strings.xml file for different screen sizes in your library, your app might use the library file.

I.E, if you have :

LIBRARY :  
    res/values/strings.xml  
    res/values-sw600dp/strings.xml

and :

APP :
    res/values/strings.xml

And you try to launch your app on a 600dp screen size (i.e a tablet), your app is going to get the strings.xml(sw600dp) from your library.
To avoid this, you might want to create a strings.xml specific to sw600dp resolutions in your app, that contains the same strings values than in your library.