MPChartExample/res/layout/activity_realtime_linechart.xml

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

    <com.github.mikephil.charting.charts.LineChart
        android:id="@+id/chart1"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>
    
</RelativeLayout>