Here’s sample piece of code in C# (for Unity). It is a simple and generic status message system, and should give some idea of what kind of practices I use when writing code. The core of the system is MessageManager, messages are held in Message objects and at the bottom is MessageManagerDemo, a simple Unity component for demonstrating usage. If you want to test the system in action, copy the three classes to a Unity project, add MessageManagerDemo component to a gameobject, and press play.
MessageManager.cs
using UnityEngine;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
namespace Lusmu.GenericTools
{
/// <summary>
/// Message manager.
///
/// Manages status messages, but does not render them on screen.
/// One instance can be accessed statically through MessageManager.Main,
/// or you can create separate instances with new MessageManager().
///
/// Add messages with Add(Message message), Add(string text) or
/// Add(string title, string text, int priority, float lifeTime, Texture image)
/// Get messages with GetTopmost() or GetMessage(int index)
/// Remove messages with RemoveTopmost(), RemoveMessage(Message message)
/// or RemoveById(int id)
/// </summary>
public class MessageManager
{
private static MessageManager instance;
public static MessageManager Main
{
get
{
if (instance == null)
{
instance = new MessageManager ();
}
return instance;
}
}
public event System.Action<Message> MessageAdded;
public int MessageCount { get { return Messages.Count; } }
public List<Message> Messages { get; set; }
public int DefaultPriority { get; set; }
public bool OrderMessagesByPriority { get; set; }
private int _maxMessages = 1000;
public int MaxMessages
{
get { return _maxMessages; }
set { if (_maxMessages > 0) _maxMessages = value; }
}
private float _defaultLifeTime = 10;
public float DefaultLifeTime
{
get { return _defaultLifeTime; }
set { if (_defaultLifeTime > 0) _defaultLifeTime = value; }
}
public MessageManager ()
{
Messages = new List<Message> ();
}
public MessageManager ( int maxMessages, float defaultLifeTime,
int defaultPriority, bool orderMessagesByPriority)
{
this.MaxMessages = maxMessages;
this.DefaultLifeTime = defaultLifeTime;
this.DefaultPriority = defaultPriority;
this.OrderMessagesByPriority = orderMessagesByPriority;
}
// ================================================================
#region public API
/// <summary>
/// Gets the message that should be displayed next.
/// </summary>
public Message GetTopmost()
{
return GetMessage(0);
}
/// <summary>
/// Gets the message with specified index from the message queue.
/// </summary>
public Message GetMessage (int index)
{
if (index < Messages.Count) return Messages [index];
else return null;
}
/// <summary>
/// Adds a message to its appropriate place in the message queue.
/// </summary>
public void AddMessage (string text)
{
AddMessage (string.Empty, text, DefaultPriority, DefaultLifeTime, null);
}
/// <summary>
/// Adds a message to its appropriate place in the message queue.
/// </summary>
public void AddMessage (string title, string text, int priority,
float lifeTime, Texture image)
{
Message message = new Message (title, text, priority, image, lifeTime);
AddMessage (message);
}
/// <summary>
/// Adds a message to its appropriate place in the message queue.
/// </summary>
public void AddMessage (Message message)
{
if (OrderMessagesByPriority)
{
int index = 0;
for (index = 0; index < Messages.Count; index++)
{
if (message.priority > Messages [index].priority) break;
}
Messages.Insert (index, message);
}
else
{
Messages.Add (message);
}
if (Messages.Count > MaxMessages)
{
RemoveLowestOldest();
}
OnAddMessage(message);
}
/// <summary>
/// Removes the topmost message from the message queue.
/// </summary>
public void RemoveMessage (Message message)
{
Messages.Remove (message);
}
/// <summary>
/// Removes the topmost message from the message queue.
/// </summary>
public void RemoveTopmost()
{
RemoveMessage(0);
}
/// <summary>
/// Removes a message from message queue by its id number.
/// </summary>
public void RemoveById(int id)
{
Message message = Messages.FirstOrDefault(m => m.messageId == id);
if (message != null) Messages.Remove(message);
}
/// <summary>
/// Removes a message by its index in the message queue.
/// </summary>
public void RemoveMessage(int index)
{
if (index >= 0 && index < MessageCount)
{
Messages.RemoveAt(index);
}
}
/// <summary>
/// Removes all messages at or below the specified priority.
/// </summary>
public void RemoveByPriority(int priorityToRemove)
{
for (int i = Messages.Count - 1; i >= 0; i--)
{
if (Messages[i].priority <= priorityToRemove)
{
Messages.RemoveAt(i);
}
}
}
/// <summary>
/// Removes the oldest message of the lowest priority.
/// </summary>
public void RemoveLowestOldest()
{
Message messageToRemove
= Messages.OrderByDescending(m => m.priority).FirstOrDefault();
if (messageToRemove != null)
{
Messages.Remove(messageToRemove);
}
}
/// <summary>
/// Clears the message list.
/// </summary>
public void Clear()
{
Messages.Clear();
}
#endregion
void OnAddMessage(Message message)
{
// Only raise the event if message was added successfully
if (MessageAdded != null && Messages.Contains(message))
{
MessageAdded(message);
}
}
}
}
Message.cs
using UnityEngine;
namespace Lusmu.GenericTools
{
/// <summary>
/// A message.
///
/// Can contain title, text and image.
/// Also has priority, lifetime and timestamp.
/// The message is equipped with a readonly messageId,
/// that is based on static messageCount.
/// </summary>
public class Message
{
public string title = string.Empty;
public string text;
public Texture image = null;
public int priority = 10;
public System.DateTime timestamp;
public readonly int messageId;
public float lifeTime = 10;
public static int messageCount { get; private set; }
public Message (string text)
: this (string.Empty, text, 10, null, 10)
{}
public Message (string title, string text, int priority)
: this (title, text, priority, null, 10)
{}
public Message (string title, string text, int priority,
Texture image, float lifeTime)
{
this.title = title;
this.text = text;
this.priority = priority;
this.timestamp = System.DateTime.Now;
this.image = image;
this.lifeTime = lifeTime;
messageId = messageCount;
messageCount ++;
}
public override string ToString()
{
return messageId + " " + title + " " + text;
}
}
}
MessageManagerDemo.cs
using UnityEngine;
using Lusmu.GenericTools;
public class MessageManagerDemo : MonoBehaviour
{
MessageManager manager;
Message current;
void Start()
{
manager = MessageManager.Main;
manager.MessageAdded += OnAddMessage;
}
void OnDestroy()
{
// Remember to remove event listener
if (manager != null)
manager.MessageAdded -= OnAddMessage;
}
void Update ()
{
if (current != null)
{
// Age the current message,
// and remove if lifeTime spent
current.lifeTime -= Time.deltaTime;
if (current.lifeTime <= 0)
{
manager.RemoveTopmost();
current = manager.GetTopmost();
}
}
}
void OnAddMessage(Message newMessage)
{
// When a message is added, show it unless it has a lower
// priority then current
if (current == null || newMessage.priority > current.priority)
{
current = newMessage;
}
}
void OnGUI()
{
if (current != null)
{
// Draw current message text
GUI.Label(new Rect(10, 10, Screen.width - 20, 30),
current.text);
// Button for removing the current, and showing next
if (GUI.Button(new Rect(10, 100, 250, 50), "Next"))
{
manager.RemoveTopmost();
current = manager.GetTopmost();
}
}
// Show how many messages in queue
if (manager.MessageCount > 1)
{
GUI.Label(new Rect(10, 50, Screen.width - 20, 30),
(manager.MessageCount - 1) + " more messages in queue");
}
// Button for adding a message with random message
if (GUI.Button(new Rect(10, 170, 250, 50), "Add Random message"))
{
manager.AddMessage("A message with a number " + Random.Range(1, 999));
}
}
}
