Android Tablayout 将 textAllCaps 设置为 False 不起作用

我正在尝试将我的 ViewPager Tab 文本设为小写，但它不起作用，

我已经搜索并检查了与此相关的其他帖子，尝试了他们的解决方案，但仍然无效

I have searched and checked other post related to this, tried their solution, but still doesn't work

<style name="MyCustomTabLayout" parent="Widget.Design.TabLayout">
      <item name="tabTextAppearance">@style/MyCustomTextAppearance</item>
</style>

<style name="MyCustomTextAppearance" parent="TextAppearance.Design.Tab">
      <item name="textAllCaps">false</item>
</style>

ViewPager 标签布局

<android.support.design.widget.TabLayout
        android:id="@+id/tabs"
        app:textAllCaps="false"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:theme="@style/MyCustomTabLayout" />

请问有任何已确认的可行解决方案吗?

Please any confirmed working solution to this?

谢谢.