<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:orientation="vertical"
              android:layout_width="match_parent"
              android:layout_height="match_parent">

    <com.github.mikephil.charting.charts.CombinedChart
        android:id="@+id/my_chart"
        android:layout_centerInParent="true"
        android:layout_width="match_parent"
        android:layout_height="300dp"/>

</RelativeLayout>