FloatingActionButton with text instead of image

Question

I'm trying to figure out how can be modified FloatingActionButton from android support library. Can it be used with the text instead of image?

Something like this one:

I see it extends ImageButton so I think not. Am I right?

Is this correct in terms of Material Design in general?

Answer 1

Thanks to all.

Here is easy workaround which I found for this question. Works correctly for Android 4+, for Android 5+ is added specific parameter android:elevation to draw TextView over FloatingActionButton.

<FrameLayout
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_gravity="bottom|right">

    <android.support.design.widget.FloatingActionButton
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@android:color/transparent" />

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:text="@android:string/ok"
        android:elevation="16dp"
        android:textColor="@android:color/white"
        android:textAppearance="?android:attr/textAppearanceMedium" />
</FrameLayout>