Button to start ranging for beacons and tutorial help neded

Hello community, I started my project on estimote beacons 3 weeks ago and manage to get the app work with the tutorial they provided. As I want to enhance the codes that they provided for me, I face some difficulty in doing so. Hoping that I would receive some feedback that can help me.

Tutorial link: http://developer.estimote.com/android/tutorial/part-2-background-monitoring/

Problem 1: Is there a way that I can implement a button to start ranging for beacons instead of automatically detecting beacons and receiving notification? I tired ways to put the ranging code to the button handler action but can’t seemed to work.

Problem 2: I have some difficulty in understanding tutorial 3
link: http://developer.estimote.com/android/tutorial/part-3-ranging-beacons/

Beacon nearestBeacon = list.get(0);
List places = placesNearBeacon(nearestBeacon);
// TODO: update the UI here
Log.d(“Airport”, "Nearest places: " + places);

I am not quite sure of the line TODO: update the UI here, I have read through many times and the hint they gave me was “list view” so I researched online and tried to experiment and play around it with the tutorial file but can’t seemed to work…

Hopefully someone can guide me and provide me sample code for me to understand.
Thank you for your time reading this !