MTI860_VR_Multi_Controller/Assets/OmniSDK/Scripts/OmniService.cs

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

public class OmniService 
{
    public static bool isPresent()
    {
        var xrDisplaySubsystems = new List<XRDisplaySubsystem>();
        SubsystemManager.GetInstances<XRDisplaySubsystem>(xrDisplaySubsystems);
        foreach (var xrDisplay in xrDisplaySubsystems)
        {
            if (xrDisplay.running)
            {
                return true;
            }
        }
        return false;
    }
}