SBC_Main_Android/app/src/main/res/drawable/bg_recyclerview_header.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
    <gradient
        android:angle="90"
        android:startColor="@color/colorBackground"
        android:endColor="@color/colorToolbar"
        android:centerColor="@color/colorBackground"
        android:type="linear" />
    <corners android:topLeftRadius="8dp" android:topRightRadius="8dp"/>
</shape>