Obtaining custom xml attribute for Android fragment on 5.0

Question

I am trying to retrieve a value for a custom attribute I have defined for a Fragment. My issue is that the returned value for the custom attribute when accessed by TypedArray.getInteger() is always 0 instead of the value that was set in the layout file - but only on devices running 5.0.

To reference a few resources I have found to be helpful in trying to solve my problem: Google's FragmentArgument demo for obtaining custom styled attributes, this stackoverflow post which has been referenced on a few other stackoverflow questions regarding obtaining custom attributes for Android Fragments, and this article.

Using these resources, I have successfully obtained custom attributes set for a fragment on devices running api 16 - 19, but not on devices running Android L.

Code snippets:

res/values/attrs.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <declare-styleable name="ComposerFragment">
        <attr name="position" format="enum">
            <enum name="left" value="1"/>
            <enum name="right" value="2"/>
        </attr>
    </declare-styleable>
</resources>

composer_activity.xml (layout file)

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    >

    <!-- other views elided -->

    <fragment
        android:name="com.mypackage.name.ui.fragment.ComposerFragment"
        android:id="@+id/left_composer"
        <!-- layout attributes elided -->
        app:position="left">
        <requestFocus/>
    </fragment>

    <fragment
        android:name="com.mypackage.name.ui.fragment.ComposerFragment"
        android:id="@+id/right_composer"
        <!-- layout attributes elided -->
        app:position="right"
     />
</RelativeLayout>

ComposerFragment.java (extends support Fragment)

@Override
public void onInflate(Activity activity, AttributeSet attrs, Bundle savedInstanceState) {
    super.onInflate(activity, attrs, savedInstanceState);
    TypedArray a = activity.obtainStyledAttributes(attrs, R.styleable.ComposerFragment);
    mBackgroundScrollerPosition =
            a.getInteger(R.styleable.ComposerFragment_position, Position.NOT_SPECIFIED);  // Position.NOT_SPECIFIED == 0
    a.recycle();
}

I have tried <attr name="position" format="integer"> in attrs.xml and just setting app:position="1" in the layout xml, but the value returned in a.getInteger(R.styleable.ComposerFragment_position, Position.NOT_SPECIFIED); is always 0 - on devices running 5.0.

As previously stated, my approach works on devices running JellyBean and KitKat.