linphone-android/res/drawable/fast_scroll_preview.xml

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
	<item>
	    <shape android:shape="rectangle">
	        <size android:width="70dp" android:height="70dp"/>
	        <solid android:color="@color/colorA" />
	    </shape>
	</item>
</layer-list>