UI draw line

using System.Collections.Generic;
using UnityEngine;

public class UIDrawLine : MonoBehaviour
 {
   private List<RectTransform> _lineRect = new List<RectTransform>();
   
   private Transform _lines;
   //  Draw a line 
   private void CreateLine() 
   {
      for (int i = 0; i < _lineRect.Count; i++)
      {
         if (i == _lineRect.Count - 1) return;

         Vector2 lineStart = _lineRect[i].anchoredPosition;
         Vector2 lineEnd = _lineRect[i + 1].anchoredPosition;
               
         GameObject line = PoolManager.instance.getItem("LiveCenterWindow", AssetBundleType.UI, "Line");

         line.SetActive(true);
         line.transform.SetParent(_lines);
         line.transform.localScale = Vector3.one;
         line.transform.SetSiblingIndex(0);

         // Adjust height to proper sizing
         RectTransform rectTrans = line.GetComponent<RectTransform>();
         float tempHeight = Vector2.Distance(lineStart, lineEnd);
         rectTrans.sizeDelta = new Vector2(rectTrans.rect.width, tempHeight);

         // Adjust rotation and placement
         rectTrans.rotation = HelperRotate2D(lineStart, lineEnd);
         rectTrans.anchoredPosition = lineStart;
      }
   }

   private static Quaternion HelperRotate2D (Vector3 start, Vector3 end) 
   {
      Vector3 diff = start - end;
      diff.Normalize();
      float rotZ = Mathf.Atan2(diff.y, diff.x) * Mathf.Rad2Deg;
      return Quaternion.Euler(0f, 0f, rotZ - 90f);
   }
}