Unity Simple UI Toggle and save

using UnityEngine;
using UnityEngine.UI;
using UnityEngine.EventSystems;

public class UI_Toggle : MonoBehaviour, IPointerClickHandler, IPointerDownHandler, IPointerUpHandler {

    public Image _Button;

    public Vector3 _Scale_Pressed;
    private Vector3 _Scale_Normal;

    public string _prefStringTitle = "prefStringTitle";

    public Sprite _ON_Image;
    public Sprite _OFF_Image;

    private int _currentValue = 1;

    void OnEnable(){
        _currentValue = PlayerPrefs.GetInt ( _prefStringTitle , 1);
        _Scale_Normal = _Button.rectTransform.localScale;
        Toggle_Fire();
    }

    public void Toggle_Fire(){
        if (_currentValue == 1) {
            _Button.sprite = _ON_Image;
        } else {
            _Button.sprite = _OFF_Image;
        }

        Debug.Log ("Prefs Update: Toggle: " + _prefStringTitle.ToString() + " = " + _currentValue);

        PlayerPrefs.SetInt ( _prefStringTitle ,  _currentValue);
        PlayerPrefs.Save();
    }

    public void OnPointerDown( PointerEventData eventData )
    {
        _Button.rectTransform.localScale = _Scale_Pressed;
    }

    public void OnPointerUp( PointerEventData eventData )
    {
        _Button.rectTransform.localScale = _Scale_Normal;
    }

    public void OnPointerClick( PointerEventData eventData )
    {
        if (_currentValue == 1) {
            _currentValue = 0;
        } else {
            _currentValue = 1;
        }
        Toggle_Fire ();
    }
}