I managed to solve my problem, here is what was needed for anyone who is stuck on this in future:
Creating my own actionBarTabText style seems to be the right way to go. Even though I set the theme of the application in the AndroidManifest as: android:theme="@style/CustomActionBarTheme"
, the actual text was being created in a TextView within a linear layout which meant that the style was not being applied to it.
This explains why the other style elements such as the tabs and actionbar backgrounds were being styled but the text was not as they were not created in the layout. To solve this, in my TextView I just set the style attribute to that of the "TabTextStyle" I had created in themes.xml.
I still do not fully understand why I had to apply the particular style manually even though it should have been set as part of the "CustomActionBarTheme" in the AndroidManifest. Anyway, this fix works so here is the code below:
<TextView
android:id="@+id/friend_tab_title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="-10dp"
android:layout_gravity="center"
android:text="FRIENDS"
style="@style/TabTextStyle"/>