yichael_smartbow/Assets/BowArrow/Scripts/Game/GameEventCenter.cs

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

public class GameEventCenter : MonoBehaviour
{   
    public System.Action<ArmBow, Arrow> onBowArrowShootOut;

    private static GameEventCenter _ins;
    public static GameEventCenter ins {
        get {
            if (!_ins) {
                _ins = new GameObject().AddComponent<GameEventCenter>();
            }
            return _ins;
        }
    }
}