Cannot lower case button text in android studio

I have a trivial question that has been bothering me for a while. I tried to google this but no one seems to have the same problem as me or doesn't see it as an issue. When I make a button in activity_my.xml under layout

 <Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/button_1_name"
    android:id="@+id/button2"
    android:layout_marginTop="140dp"
    android:layout_below="@+id/textView"
    android:layout_centerHorizontal="true" />

I get a button that looks like

even though my strings code is:

<resources>

<string name="app_name">HelloWorld</string>
<string name="hello_world">Hello world!</string>
<string name="action_settings">Settings</string>
<string name="button_1_name">BuTtOn 1</string>

I know I am definitely missing something small here, but how do I get lower case/upper case working in the button text?

Thanks!

You could add android:textAllCaps="false" to the button.

The button text might be transformed to uppercase by your app's theme that applies to all buttons. Check themes / styles files for setting the attribute android:textAllCaps.

<style name="AppTheme" parent="AppBaseTheme">
    <item name="android:buttonStyle">@style/Button</item>
</style>

<style name="Button" parent="Widget.AppCompat.Button">
    <item name="android:textAllCaps">false</item>
</style>

This is fixable in the application code by setting the button's TransformationMethod null, e.g.

mButton.setTransformationMethod(null);