AndroidAPS/app/src/main/res/layout/overview_fragment.xml

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="info.nightscout.androidaps.plugins.Overview.OverviewFragment">


    <LinearLayout
        android:orientation="vertical"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <TextView
            android:id="@+id/overview_bg"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="left|top"
            android:textSize="100dp" />

        <com.jjoe64.graphview.GraphView
            android:id="@+id/overview_bggraph"
            android:layout_width="match_parent"
            android:layout_height="200dip" />
    </LinearLayout>

</FrameLayout>