SafeKeyboard/app/src/main/res/drawable/keyboard_selector_bg.xml

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">

    <item android:state_checked="false" android:state_pressed="false">
        <shape android:shape="rectangle">
            <solid android:color="#474749" />
            <corners android:radius="5dp" />
        </shape>
    </item>

    <item android:state_checked="false" android:state_pressed="true">
        <shape android:shape="rectangle">
            <solid android:color="#1c69ac" />
            <corners android:radius="5dp" />
        </shape>
    </item>

</selector>