Hacking Android Styles

I never did android development, only the React Native side of things. Now while digging deeper, trying to figure out how to style a React Native picker on android (because the default is really ugly) I am reading into android docs. I found out how to break my app's rendering with one line of XML. Not true, five lines of XML.

In "android/app/src/main/res/values/style.xml" I can style theme my app. By simply overriding the style android:textViewStyle like you see below I can change all <Text> components used in my app that do not override any of the attributes you see below.

<resources>
    <!-- Base application theme. -->
    <style name="AppTheme" parent="Theme.AppCompat.Light.NoActionBar">
        <!-- Customize your theme here. -->
        <item name="android:textViewStyle">@style/TextView</item>
    </style>

    <style name="TextView" parent="AppTheme">
        <item name="android:textColor">#ff0000</item>
        <item name="android:padding">20dp</item>
        <item name="android:gravity">center</item>
    </style>

I have overridden textColor, padding and gravity (which is kinda like justifyContent in flexbox-speak). And boom I had a couple of red texts that became centered in my app. I guess that also means I did not yet properly style all elements.