ANTM/Assets/Scripts/InGameNotificationManager.cs

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

public class InGameNotificationManager : MonoBehaviour {

    public static InGameNotificationManager Instance; 

    public UIElementsGroup NotificationUI;
    public Text Title;
    public Text Body;

    private bool activeNotification;

    private List<NotificationData> queuedNotifications = new List<NotificationData>();

    public struct NotificationData
    {
        public string Title;
        public string Body;

        public NotificationData(string title, string body)
        {
            Title = title;
            Body = body;
        }
    }

    void Awake()
    {
        Instance = this;
    }

    void Update()
    {
        if (Input.GetKeyDown("n"))
            PopNotification("Quest Completed!", "Your First Gig");
    }
    
    public void PopNotification(string title, string body)
    {
        if (activeNotification)
        {
            queuedNotifications.Add(new NotificationData(title, body));
            return;
        }

        NotificationUI.ChangeVisibility(true);
        Title.text = title;
        Body.text = body;
        StartCoroutine(ExtraLetter());
        Invoke("CloseNotification", 3);

        activeNotification = true;
    }

    IEnumerator ExtraLetter()
    {
        yield return null;
        Body.text += " ";
        yield return null;
        Body.text = Body.text.Substring(0, Body.text.Length -1);

    }

    public void CloseNotification()
    {
        activeNotification = false;

        NotificationUI.ChangeVisibility(false);
        CancelInvoke("CloseNotification");

        if (queuedNotifications.Count > 0)
        {
            NotificationUI.ChangeVisibilityImmediate(false);

            NotificationData qData = queuedNotifications[0];
            PopNotification(qData.Title, qData.Body);

            queuedNotifications.RemoveAt(0);
        }
    }
}