Unity script that enables/disables a gameobject (like a warning text) when the user presses the System Button in SteamVR

SteamVROverlayCheck.cs

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

public class SteamVROverlayCheck : MonoBehaviour
{

    public GameObject warningDisplay;

    void OnEnable()
    {
        SteamVR_Events.InputFocus.AddListener(OnFocus);
    }

    void OnDisable()
    {
        SteamVR_Events.InputFocus.RemoveListener(OnFocus);
    }

    void OnFocus(bool focusState)
    {
        warningDisplay.SetActive(!focusState);
    }


}