ICTS_2021/Unity3/Assets/UI/ScrollToTop.cs

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

/// <summary>
/// This component should be placed on a UIScrollbar and is responsible for scrolling it to the top.
/// This is useful for dynamic content inside a scrollable panel
/// </summary>
public class ScrollToTop : MonoBehaviour
{
	Scrollbar scrollBar;

	void Awake()
	{
		scrollBar = GetComponent<Scrollbar>();
	}

	void OnEnable()
	{
		StartCoroutine(ResetScrollCoroutine());
	}

	IEnumerator ResetScrollCoroutine()
	{
		yield return new WaitForSeconds(0.5f); //wait for transition
		iTween.ValueTo(gameObject, iTween.Hash(
			"from", scrollBar.value,
			"to", 0,
			"time", 0.5f,
			"easetype", iTween.EaseType.easeOutCubic,
			"onupdate", "UpdateScrollValue",
			"onupdatetarget", gameObject));
	}

	void UpdateScrollValue(float newScrollValue)
	{
		scrollBar.value = newScrollValue;
	}

}