battlearray_client/Assets/Scripts/UI/ChatPanel/ChatIcon.cs

using UnityEngine;
using System.Collections;

public class ChatIcon : MonoBehaviour
{

	public ChatBar chatBar;

	// Use this for initialization
	void Start ()
	{
		ChatManager.GetInstance ().MsgUpdate.AddListener (OnMsgUpdate);
	}

	private void OnMsgUpdate()
	{
		if (chatBar.isShown) {
			RedDot.SetValue (this.transform, 0);
			return;
		}

		ChatManager chatMan = ChatManager.GetInstance ();
		int value = chatMan.GetNewMsgGlobalCount ();
		RedDot.SetValue (this.transform, value);
	}

	void OnDestroy()
	{
		ChatManager.GetInstance ().MsgUpdate.RemoveListener (OnMsgUpdate);
	}

}