layer_list.xml

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="<http://schemas.android.com/apk/res/android>">
    <item android:drawable="@drawable/bg_gradient"/>
    <item>
         <bitmap 
             android:gravity="center"
             android:src="@drawable/logo_art_1"/>
    </item>
    <item android:bottom="50dp"> // setting the image from bottom
        <bitmap 
            android:gravity="bottom"
            android:src="@drawable/logo_art_2"/>
    </item>
</layer-list>