(C#) ShieldPowerUp.cs

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

public class ShieldPowerUp : MonoBehaviour {

    #region Member Variables
    public static ShieldPowerUp instance;

    public bool on;
    public GameObject shieldHitVisualFX;

    public SpriteRenderer shieldActiveVisualFX;
    #endregion

    void Awake()
    {
        if (instance == null)
            instance = this;
        else
            Destroy(this);
    }

    void Start () {
        InitMembers();
    }

    //=============================

    public void ShieldTakesHit()
    {
        ShieldHitFX();
        TurnShieldOff();
    }

    #region Private Member Functions
    void InitMembers()
    {
        on = false;
        shieldActiveVisualFX.enabled = false;
    }

    void ShieldHitFX()
    {
        GameObject vfx = Instantiate(shieldHitVisualFX, gameObject.transform.position, gameObject.transform.rotation);
        vfx.GetComponent<ParticleSystem>().Play();
    }

    void TurnShieldOff()
    {
        on = false;
        shieldActiveVisualFX.enabled = false;
    }

    void TurnShieldOn()
    {
        on = true;
        shieldActiveVisualFX.enabled = true;
    }
    #endregion
}