Selector & Ripple

btn_selector.xml

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

    <item android:id="@+id/mask">
        <shape>
            <solid android:color="BUTTON_COLOR">
            </solid>
        </shape>
    </item>
</ripple>

btn_selector2.xml

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:state_pressed="true">
        <shape>
            <solid android:color="BUTTON_COLOR_PRESSED"/>
        </shape>
    </item>

    <item>
        <shape>
            <solid android:color="BUTTON_COLOR"/>
        </shape>
    </item>
</selector>