android-calculatorpp/android-app/res/values/theme_violet.xml

<?xml version="1.0" encoding="utf-8"?>
<!--
  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
  ~ For more information, please, contact se.solovyev@gmail.com
  ~ or visit http://se.solovyev.org
  -->

<resources>
	<style name="violet_digit_button_style" parent="cpp_keyboard_button_style">
		<item name="android:background">@drawable/violet_button</item>
	</style>

	<style name="violet_operation_button_style" parent="violet_digit_button_style">
			<item name="android:textColor">@color/cpp_button_operator_text_color</item>
	</style>

	<style name="violet_control_button_style" parent="cpp_keyboard_button_style">
		<item name="android:background">@drawable/violet_button_dark</item>
	</style>

	<style name="violet_control_image_button_style" parent="violet_control_button_style">
		<item name="android:padding">6dp</item>
	</style>

	<style name="cpp_violet_theme" parent="cpp_gray_theme">
		<item name="cpp_digit_button_style">@style/violet_digit_button_style</item>
		<item name="cpp_control_button_style">@style/violet_control_button_style</item>
		<item name="cpp_control_image_button_style">@style/violet_control_image_button_style</item>
		<item name="cpp_operation_button_style">@style/violet_operation_button_style</item>
	</style>
</resources>