Focus/center Scroll View to the specified point/item in Unity

ScrollViewFocusFunctions.cs

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

public static class ScrollViewFocusFunctions
{
	public static Vector2 CalculateFocusedScrollPosition( this ScrollRect scrollView, Vector2 focusPoint )
	{
		Vector2 contentSize = scrollView.content.rect.size;
		Vector2 viewportSize = ( (RectTransform) scrollView.content.parent ).rect.size;
		Vector2 contentScale = scrollView.content.localScale;

		contentSize.Scale( contentScale );
		focusPoint.Scale( contentScale );

		Vector2 scrollPosition = scrollView.normalizedPosition;
		if( scrollView.horizontal && contentSize.x > viewportSize.x )
			scrollPosition.x = Mathf.Clamp01( ( focusPoint.x - viewportSize.x * 0.5f ) / ( contentSize.x - viewportSize.x ) );
		if( scrollView.vertical && contentSize.y > viewportSize.y )
			scrollPosition.y = Mathf.Clamp01( ( focusPoint.y - viewportSize.y * 0.5f ) / ( contentSize.y - viewportSize.y ) );

		return scrollPosition;
	}

	public static Vector2 CalculateFocusedScrollPosition( this ScrollRect scrollView, RectTransform item )
	{
		Vector2 itemCenterPoint = scrollView.content.InverseTransformPoint( item.transform.TransformPoint( item.rect.center ) );

		Vector2 contentSizeOffset = scrollView.content.rect.size;
		contentSizeOffset.Scale( scrollView.content.pivot );

		return scrollView.CalculateFocusedScrollPosition( itemCenterPoint + contentSizeOffset );
	}

	public static void FocusAtPoint( this ScrollRect scrollView, Vector2 focusPoint )
	{
		scrollView.normalizedPosition = scrollView.CalculateFocusedScrollPosition( focusPoint );
	}

	public static void FocusOnItem( this ScrollRect scrollView, RectTransform item )
	{
		scrollView.normalizedPosition = scrollView.CalculateFocusedScrollPosition( item );
	}

	private static IEnumerator LerpToScrollPositionCoroutine( this ScrollRect scrollView, Vector2 targetNormalizedPos, float speed )
	{
		Vector2 initialNormalizedPos = scrollView.normalizedPosition;

		float t = 0f;
		while( t < 1f )
		{
			scrollView.normalizedPosition = Vector2.LerpUnclamped( initialNormalizedPos, targetNormalizedPos, 1f - ( 1f - t ) * ( 1f - t ) );

			yield return null;
			t += speed * Time.unscaledDeltaTime;
		}

		scrollView.normalizedPosition = targetNormalizedPos;
	}

	public static IEnumerator FocusAtPointCoroutine( this ScrollRect scrollView, Vector2 focusPoint, float speed )
	{
		yield return scrollView.LerpToScrollPositionCoroutine( scrollView.CalculateFocusedScrollPosition( focusPoint ), speed );
	}

	public static IEnumerator FocusOnItemCoroutine( this ScrollRect scrollView, RectTransform item, float speed )
	{
		yield return scrollView.LerpToScrollPositionCoroutine( scrollView.CalculateFocusedScrollPosition( item ), speed );
	}
}