iTweenでuGUIの色をかえる

ChangeColor.cs

using UnityEngine;
using UnityEngine.UI;

public class ChangeColor : MonoBehaviour
{
    private Image target;
    private Color originalColor;
    
    void Awake()
    {
        this.target = this.gameObject.GetComponent<Image>();
    }
    
    public void OnChangeColor(Button sender)
    {
        this.originalColor = this.target.color;
        iTween.ValueTo(
            this.gameObject,
            iTween.Hash(
                "time", 2f,
                "from", 0f,
                "to",   1f,
                "onupdate", "ChangeColorToYellow",
                "oncomplete", "OnComplete",
                "oncompleteparams", sender
            )
        );
    }
    
    public void ChangeColorToYellow(float newValue)
    {
        var diff = Color.yellow - this.originalColor;
        this.target.color = new Color(
            this.originalColor.r + diff.r * newValue,
            this.originalColor.g + diff.g * newValue,
            this.originalColor.b + diff.b * newValue
        );
    }
    
    public void OnComplete(Button sender)
    {
        sender.gameObject.GetComponentInChildren<Text>().text = "Fin...";
    }
}