UI verticalNormalizedPosition not going to bottom of the scroll view

I am working with the photon network to make a simple game. I would like this game to implement a simple chat system, however, I have run into a snag.

The problem comes from the fact that I am unable to make the scroll view, which I am using to display the chat, scroll all the way to the bass, or the last message sent.

Bellow is the code I am using.

Code (CSharp):

1. using UnityEngine;
2. using UnityEngine.UI;
3. using System.Collections.Generic;
4.  
5. public class ChatBarManager : MonoBehaviour {
6.  
7.     [SerializeField] private RectTransform m_Content;
8.     [SerializeField] private GameObject m_MessageObject;
9.     [SerializeField] private float m_TextObjectHeight = 30.0f;
10.  
11.     private List<GameObject> m_Messages = new List<GameObject>();
12.     private float m_ContentHeight = 300;
13.  
14.     void Start()
15.     {
16.         m_Content.localPosition = new Vector3(0, 0, 0);
17.     }
18.  
19.     public void AddMessage(string message)
20.     {
21.         GameObject newMessage = (GameObject)Instantiate(m_MessageObject);
22.         newMessage.transform.SetParent(m_Content, false);
23.         newMessage.GetComponent<Text>().text = message;
24.         ((RectTransform)newMessage.transform).anchoredPosition = new Vector2(0, -(m_TextObjectHeight * m_Messages.Count));
25.         m_Messages.Add(newMessage);
26.  
27.         if (m_Messages.Count * m_TextObjectHeight > 200)
28.         {
29.             m_Content.GetComponentInParent<ScrollRect>().verticalNormalizedPosition = 0;
30.         }
31.  
32.             if (m_Messages.Count * m_TextObjectHeight > m_ContentHeight)
33.         {
34.             m_Content.sizeDelta = new Vector2(0, m_ContentHeight + m_TextObjectHeight);
35.             m_ContentHeight = m_ContentHeight + m_TextObjectHeight;
36.         }
37.     }
38.    
39. }

While this code does indeed make the scroll view move down it only moves far enough to show the second last message send.

I have made so that the code works with the scroll view created when you first create a scroll view
Create > UI >Scroll View

The m_MessageObject is just a normal text object I saved as a prefab.

Any help would be appreciated.

 

You'll probably have to wait a frame or do a LayoutRebuilder.ForceLayoutRebuildImmediate(m_Content) before setting of the scroll rect position will work.

 

Thank you very much. I used an IEnumerator to wait for a frame and then ran the verticalNormalizedPosition = 0.
This returned the desired result.

Again thank you.