arfoundation-samples/Assets/Scenes/ARCollaborationData/DisplayTrackingState.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
using UnityEngine.XR.ARFoundation;

/// <summary>
/// When relocalizing with ARCollaborationData or ARWorldMaps, the tracking state
/// should change to TrackingState.Limited until the device has successfully
/// relocalized to the new data. If it remains TrackingState.Tracking, then
/// it is not working.
/// </summary>
[RequireComponent(typeof(ARSession))]
public class DisplayTrackingState : MonoBehaviour
{
    [SerializeField]
    Text m_Text;

    public Text text
    {
        get { return m_Text; }
        set { m_Text = value; }
    }

    ARSession m_Session;

    void Start()
    {
        m_Session = GetComponent<ARSession>();
    }

    void Update()
    {
        if (text != null)
        {
            text.text = $"Session ID = {m_Session.subsystem.sessionId}\n" +
                        $"Session state = {ARSession.state.ToString()}\n" +
                        $"Tracking state = {m_Session.subsystem.trackingState}";
        }
    }
}