Correct way to style Android Lollipop 5.0 toolbar

I've been banging my head about this for a few seconds now with no luck. I am using android.support.v7.widget.Toolbar

in my app (which supports Android API 11 and above) and want to style it. This is how I do it:

My Activity Layout XML contains:

        <android.support.v7.widget.Toolbar
        xmlns:app="http://schemas.android.com/apk/res-auto"
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        app:theme="?attr/foo" />

      

        
        
        
      

    

res / values ​​/attr.xml (this is where I define my attributes):

        <attr name="foo" format="reference" />

      

        
        
        
      

    

Res / value / Themes.xml :

    <style name="AppTheme" parent="Theme_one">
    </style>
    <style name="Theme_one" parent="@style/Theme.AppCompat.Light">
        <item name="windowActionBar">false</item> 
        <item name="foo">@style/foo_style</item>
        <!-- bunch of other styles -->
    </style>

      

        
        
        
      

    

Res / value / styles.xml :

<style name="foo_style" parent="@style/Theme.AppCompat.Light">
    <item name="android:background">@color/actionBarDark</item>
</style>

      

        
        
        
      

    

Res / value-v21 / Themes.xml :

<style name="AppTheme" parent="Theme_one">
    <!-- some v21 specific items not related to toolbar like animations etc-->
</style>

      

        
        
        
      

    

Res / value-v21 / styles.xml :

<style name="foo_style" parent="@style/Theme.AppCompat.Light">
    <item name="android:colorPrimaryDark">@color/actionBarDark</item> <!-- THIS DOES NOT WORK !!! -->
    <item name="android:background">@color/actionBarDark</item>
    <item name="android:elevation">5dp</item>
</style>

      

        
        
        
      

    

This scheme works great for Android API v11 - v19. My problems for v21 (I also tried 2 and 3 without prefix android:

with the same result):

1) android: background works great!
2) android: colorPrimaryDark doesn't work!
3) android: height refers to the name of the buttons Toolbar

and Toolbar

as shown below. Is this expected?

What am I missing? It is clear that I am not doing the styling correctly, but cannot find any resources that talk about styling Toolbar

!