How to make simple XNA buttons?

Question

I was wondering if anyone could show me an easy way to create buttons in XNA.

Preferably, a method of adding a function when it is pressed and a method of easily adding and removing it.

Answer 1

I recommend using the NeoForce Controls Library for GUI-related tasks - it has buttons, among other useful GUI controls, including pop-ups, list views, combo boxes, etc.

If you are writing a button class for training ... well, try to learn more about it yourself through Google before asking for help.

ADDITION

This is the code I wrote for the buttons. Perhaps this may serve as a starting point. I use it in my 2D engine, so it has been debugged and tested.

/// <summary> /// A control that changes appearance when it is hovered over and triggers some effect when it is clicked /// </summary> public class EnigmaButton { /// <summary> /// The method signature for notification when a button is clicked /// </summary> /// <param name="sender">EnigmaButton that was clicked</param> public delegate void OnClickEvent(EnigmaButton sender); /// <summary> /// Types of textures used for Enigma Buttons /// </summary> public enum TextureType { Normal, Over, Press } #region Variables protected IVisualExposer m_ui; protected Rectangle m_bounds; IInputExposer m_input; bool m_over = false, m_press = false, m_wasPressed = false; Dictionary<TextureType, EnigmaResource<Texture2D>> m_textures; string m_text, m_name; EnigmaResource<SpriteFont> m_font; int m_minTextShadow, m_maxTextShadow; Color m_textTint; public event OnClickEvent OnClick; #endregion /// <summary> /// A control that changes appearance when it is hovered over and triggers some effect when it is clicked /// </summary> /// <param name="ui">Graphical assets</param> /// <param name="input">Input exposer for mouse input and XBox controller input</param> /// <param name="reader">XMLReader for the definition of the controller</param> /// <param name="pos">Bounds of the controller</param> public EnigmaButton(IVisualExposer ui, IInputExposer input, XmlReader reader, Rectangle pos) { m_ui = ui; m_bounds = pos; m_textures = new Dictionary<TextureType, EnigmaResource<Texture2D>>(); m_input = input; Enabled = true; #region Reading string name; bool started = false, insideText = false; while (reader.Read()) { if (reader.MoveToContent() == XmlNodeType.Element) { name = reader.Name.ToLower(); if (name == "button") { if (started) throw new Exception("Already started."); started = true; m_name = reader.GetAttribute("name") ?? string.Empty; } else if (!started) throw new Exception("Not started"); else if (name == "text") { m_font = new EnigmaResource<SpriteFont>(); m_font.Filepath = reader.GetAttribute("font"); string minShadow = reader.GetAttribute("minShadow"), maxShadow = reader.GetAttribute("maxShadow"); m_minTextShadow = minShadow != null ? int.Parse(minShadow) : 0; m_maxTextShadow = maxShadow != null ? int.Parse(maxShadow) : 2; m_text = reader.GetAttribute("text") ?? string.Empty; insideText = true; m_textTint = Color.White; } else if (name == "bounds") { insideText = false; m_bounds = new Rectangle(int.Parse(reader.GetAttribute("x")), int.Parse(reader.GetAttribute("y")), int.Parse(reader.GetAttribute("width")), int.Parse(reader.GetAttribute("height"))); } else if (name == "texture") { insideText = false; TextureType texType = (TextureType)Enum.Parse(typeof(TextureType), reader.GetAttribute("type")); if (m_textures.ContainsKey(texType)) throw new Exception("A texture of type '" + texType.ToString() + "' cannot be registered twice"); EnigmaResource<Texture2D> res = new EnigmaResource<Texture2D>(); res.Filepath = reader.ReadString(); m_textures.Add(texType, res); } else if (name == "tint") { if (!insideText) throw new Exception("Tints can only be for text"); float a, r, g, b; string[] split = reader.ReadString().Split(','); if (split.Length != 4) throw new Exception("Colors must be RGBA"); r = float.Parse(split[0].Trim()); g = float.Parse(split[1].Trim()); b = float.Parse(split[2].Trim()); a = float.Parse(split[3].Trim()); m_textTint = new Color(r, g, b, a); } } } #endregion if (!m_textures.ContainsKey(TextureType.Normal)) throw new Exception("A button must have at least a '" + TextureType.Normal.ToString() + "' texture"); } #region Methods public void Initialize() { } public void LoadContent() { EnigmaResource<Texture2D> res; for (int i = 0; i < m_textures.Count; i++) { res = m_textures[m_textures.ElementAt(i).Key]; res.Resource = m_ui.Content.Load<Texture2D>(res.Filepath); m_textures[m_textures.ElementAt(i).Key] = res; } if (m_font.Filepath != null) m_font.Resource = m_ui.Content.Load<SpriteFont>(m_font.Filepath); } public void Update(GameTime gameTime) { m_wasPressed = m_press; m_over = m_bounds.Contains(m_input.MouseX, m_input.MouseY); m_press = m_over ? m_wasPressed ? m_input.IsMouseLeftPressed || m_input.IsButtonPressed(Buttons.A) : m_input.IsMouseLeftTriggered || m_input.IsButtonTriggered(Buttons.A) : false; if (!m_wasPressed && m_press && OnClick != null) OnClick(this); } public void Draw(GameTime gameTime) { Texture2D toDraw = m_textures[TextureType.Normal].Resource; if (Enabled) { if (m_press && m_textures.ContainsKey(TextureType.Press)) toDraw = m_textures[TextureType.Press].Resource; else if (m_over && m_textures.ContainsKey(TextureType.Over)) toDraw = m_textures[TextureType.Over].Resource; } m_ui.SpriteBatch.Draw(toDraw, m_bounds, Enabled ? Color.White : Color.Gray); if (m_font.Resource != null) { Vector2 pos = new Vector2(m_bounds.X, m_bounds.Y); Vector2 size = m_font.Resource.MeasureString(m_text); pos.X += (m_bounds.Width - size.X) / 2; pos.Y += (m_bounds.Height - size.Y) / 2; UIHelper.DrawShadowedString(m_ui, m_font.Resource, m_text, pos, m_textTint, m_minTextShadow, m_maxTextShadow); } } #endregion #region Properties /// <summary> /// Gets or sets the name of the button /// </summary> public string Name { get { return m_name; } set { m_name = value ?? m_name; } } /// <summary> /// Gets or sets the text drawn in the button. /// WARNING: Will overflow if the text does not normally fit. /// </summary> public string Text { get { return m_text; } set { m_text = value ?? string.Empty; } } /// <summary> /// Gets or sets the bounds of the button /// </summary> public Rectangle Bounds { get { return m_bounds; } set { m_bounds = value; } } /// <summary> /// Whether or not the control is enabled /// </summary> public bool Enabled { get; set; } #endregion }