XNA游戏：手势触控
在XNA游戏中使用到手势触控操作时，需要引入using Microsoft.Xna.Framework.Input.Touch;
空间，在该空间下下面两个类在触控编程中会用到。
TouchLocation 用来保存某一个触摸点的状态信息。
TouchCollection 是保存了当前所有触控状态（TouchLocation）的集合。
当我们把一个指头在屏幕上操作，可能会有这样三种动作：按，移动，移开。那么这三个操作在WP7的XNA里如何获取呢？我们就需要了解XNA里的TouchPanel和TouchCollection这两个类
TouchCollection touchState= TouchPanel.GetState(); Foreach(TouchLocation location in touchState) { switch(location.State) { case TouchLocationState.Pressed://按下 …… break; case TouchLocationState.Moved://移动 …… break; case TouchLocationState.Released://释放 …… break; } }
TouchLocation ：
State 触摸状态，包含4个状态
> TouchLocationState.Pressed 表示屏幕被触摸时手指按下的一瞬间
> TouchLocationState.Moved 表示手指按下后正在移动，经过测试可知，在手指按下的一瞬间State为Pressed ，在手指按下后抬起前这段时间内的状态均是Moved
> TouchLocationState.Invalid 无效状态
> TouchLocationState.Released 表示手指抬起的一瞬间
ID 表示当前触摸事件的ID，一个完成的触控事件的过程应该是“Pressed -> Moved -> Released ”在这个过程中ID是一致的，用来在多点触摸时区分触摸的每个点。
Position 触摸位置，包含两个属性
> X 当前触摸位置的X轴坐标
> Y 当前触摸位置的Y轴坐标
（横屏全屏情况下，屏幕的左上角坐标为（0，0）右下角坐标为（800,480））
和触控操作类似的还有叫“手势”的，也算复杂的触控吧。
TouchPanel.EnabledGestures = GestureType.FreeDrag;//用来指定手势，必须要先设定，否则 报错 if (TouchPanel.EnabledGestures != GestureType.None) { switch (TouchPanel.ReadGesture()) { case GestureType.Tap: //单击 break; case GestureType.DoubleTap://双击 break; case GestureType.FreeDrag://自由拖动 break; case GestureType.DragComplete://拖动完成 break; case GestureType.Flick://轻弹 break; case GestureType.Hold://按住不动 break; case GestureType.HorizontalDrag://横向拖动 break; case GestureType.None://无手势 break; case GestureType.Pinch://捏 break; case GestureType.PinchComplete://捏完 break; case GestureType.VerticalDrag://纵向拖动 break; } }
示例一各种手势的测试：
using System; using System.Collections.Generic; using System.Linq; using Microsoft.Xna.Framework; using Microsoft.Xna.Framework.Audio; using Microsoft.Xna.Framework.Content; using Microsoft.Xna.Framework.GamerServices; using Microsoft.Xna.Framework.Graphics; using Microsoft.Xna.Framework.Input; using Microsoft.Xna.Framework.Input.Touch; using Microsoft.Xna.Framework.Media; namespace Gestures { /// <summary> /// This is the main type for your game /// </summary> public class Game1 : Microsoft.Xna.Framework.Game { GraphicsDeviceManager graphics; SpriteBatch spriteBatch; SpriteFont spriteFont; String message = "Do something"; Vector2 messagePos = Vector2.Zero; Color color = Color.Black; public Game1() { graphics = new GraphicsDeviceManager(this); Content.RootDirectory = "Content"; // Frame rate is 30 fps by default for Windows Phone. TargetElapsedTime = TimeSpan.FromTicks(333333); } /// <summary> /// Allows the game to perform any initialization it needs to before starting to run. /// This is where it can query for any required services and load any non-graphic /// related content. Calling base.Initialize will enumerate through any components /// and initialize them as well. /// </summary> protected override void Initialize() { //添加各种手势的支持 TouchPanel.EnabledGestures = GestureType.Tap | GestureType.DoubleTap | GestureType.Hold | GestureType.HorizontalDrag | GestureType.VerticalDrag | GestureType.FreeDrag | GestureType.DragComplete | GestureType.Pinch | GestureType.PinchComplete | GestureType.Flick; base.Initialize(); } /// <summary> /// LoadContent will be called once per game and is the place to load /// all of your content. /// </summary> protected override void LoadContent() { // Create a new SpriteBatch, which can be used to draw textures. spriteBatch = new SpriteBatch(GraphicsDevice); //记载字体资源 spriteFont = Content.Load<SpriteFont>("SpriteFont1"); } /// <summary> /// UnloadContent will be called once per game and is the place to unload /// all content. /// </summary> protected override void UnloadContent() { // TODO: Unload any non ContentManager content here } /// <summary> /// Allows the game to run logic such as updating the world, /// checking for collisions, gathering input, and playing audio. /// </summary> /// <param name="gameTime">Provides a snapshot of timing values.</param> protected override void Update(GameTime gameTime) { // Allows the game to exit if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed) this.Exit(); //判断手势的类别 if (TouchPanel.IsGestureAvailable) { GestureSample gesture = TouchPanel.ReadGesture(); switch (gesture.GestureType) { case GestureType.Tap: message = "That was a Tap"; color = Color.Red; break; case GestureType.DoubleTap: message = "That was a Double Tap"; color = Color.Orange; break; case GestureType.Hold: message = "That was a Hold"; color = Color.Yellow; break; case GestureType.HorizontalDrag: message = "That was a Horizontal Drag"; color = Color.Blue; break; case GestureType.VerticalDrag: message = "That was a Vertical Drag"; color = Color.Indigo; break; case GestureType.FreeDrag: message = "That was a Free Drag"; color = Color.Green; break; case GestureType.DragComplete: message = "Drag gesture complete"; color = Color.Gold; break; case GestureType.Flick: message = "That was a Flick"; color = Color.Violet; break; case GestureType.Pinch: message = "That was a Pinch"; color = Color.Violet; break; case GestureType.PinchComplete: message = "Pinch gesture complete"; color = Color.Silver; break; } messagePos = gesture.Position; } base.Update(gameTime); } /// <summary> /// This is called when the game should draw itself. /// </summary> /// <param name="gameTime">Provides a snapshot of timing values.</param> protected override void Draw(GameTime gameTime) { GraphicsDevice.Clear(Color.CornflowerBlue); //绘制屏幕的文字 spriteBatch.Begin(); spriteBatch.DrawString(spriteFont, message, messagePos, color); spriteBatch.End(); base.Draw(gameTime); } } }
示例二多点触控的测试：
using System; using System.Collections.Generic; using System.Linq; using Microsoft.Xna.Framework; using Microsoft.Xna.Framework.Audio; using Microsoft.Xna.Framework.Content; using Microsoft.Xna.Framework.GamerServices; using Microsoft.Xna.Framework.Graphics; using Microsoft.Xna.Framework.Input; using Microsoft.Xna.Framework.Input.Touch; using Microsoft.Xna.Framework.Media; namespace MultiTouchMe { /// <summary> /// This is the main type for your game /// </summary> public class Game1 : Microsoft.Xna.Framework.Game { GraphicsDeviceManager graphics; SpriteBatch spriteBatch; SpriteFont spriteFont; TouchCollection touchCollection; public Game1() { graphics = new GraphicsDeviceManager(this); Content.RootDirectory = "Content"; // Frame rate is 30 fps by default for Windows Phone. TargetElapsedTime = TimeSpan.FromTicks(333333); } /// <summary> /// Allows the game to perform any initialization it needs to before starting to run. /// This is where it can query for any required services and load any non-graphic /// related content. Calling base.Initialize will enumerate through any components /// and initialize them as well. /// </summary> protected override void Initialize() { // TODO: Add your initialization logic here base.Initialize(); } /// <summary> /// LoadContent will be called once per game and is the place to load /// all of your content. /// </summary> protected override void LoadContent() { // Create a new SpriteBatch, which can be used to draw textures. spriteBatch = new SpriteBatch(GraphicsDevice); // TODO: use this.Content to load your game content here spriteFont = Content.Load<SpriteFont>("SpriteFont1"); } /// <summary> /// UnloadContent will be called once per game and is the place to unload /// all content. /// </summary> protected override void UnloadContent() { // TODO: Unload any non ContentManager content here } /// <summary> /// Allows the game to run logic such as updating the world, /// checking for collisions, gathering input, and playing audio. /// </summary> /// <param name="gameTime">Provides a snapshot of timing values.</param> protected override void Update(GameTime gameTime) { // Allows the game to exit if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed) this.Exit(); // TODO: Add your update logic here touchCollection = TouchPanel.GetState(); base.Update(gameTime); } /// <summary> /// This is called when the game should draw itself. /// </summary> /// <param name="gameTime">Provides a snapshot of timing values.</param> protected override void Draw(GameTime gameTime) { GraphicsDevice.Clear(Color.CornflowerBlue); // TODO: Add your drawing code here spriteBatch.Begin(); foreach (TouchLocation touch in touchCollection) spriteBatch.DrawString(spriteFont, "ID: " + touch.Id.ToString() + " (" + (int)touch.Position.X + "," + (int)touch.Position.Y + ")", touch.Position, Color.White); spriteBatch.End(); base.Draw(gameTime); } } }
