Add a seek bar tied to media volume.

app/src/main/res/layout/activity_main.xml

@@ -158,4 +158,13 @@
 
     </TableLayout>
 
+    <SeekBar
+        android:id="@+id/seekBar"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_below="@id/tblButtons"
+        android:layout_alignParentBottom="true"
+        android:layout_marginVertical="@dimen/activity_vertical_margin"
+        android:layout_centerHorizontal="true"/>
+
 </RelativeLayout>