XNA游戏：软键盘弹窗输入

在XNA中如果我们需要输入文字，那么我们就需要使用到软键盘了，在XNA中使用软键盘要用到Guide.BeginShowKeyboardInput方法，由于游戏的Update是会不断地执行的，所以要由Guide.IsVisible来检查弹出输入框是否已经显示出来了。

Guide.BeginShowKeyboardInput方法的参数
PlayerIndex     玩家的编号，手机是PlayerIndex.One
Title     输入窗口的标题
Description     输入窗口的描述
DefaultText     默认的文字
Callback     回调的方法
State     使用者想要传送的物件

Guide.BeginShowMessageBox时弹出一个窗口没有软键盘输入，这个方法的参数分別是
Title     窗口的标题
Text     窗口的文字
Buttons     按钮
FoucsButton     预设的按钮
Icon     图标
Callback     回调的方法
State     使用者想要传送的物件

示例

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 SIPSample
{
    /// <summary>
    /// This is the main type for your game
    /// </summary>
    public class Game1 : Microsoft.Xna.Framework.Game
    {
        GraphicsDeviceManager graphics;
        SpriteBatch spriteBatch;

        SpriteFont spriteFont;

        string sipTitle = "This is the title.";
        string sipDescription = "This is the description that goes beneath the title.";
        string sipResult = "You type stuff here.";

        public Game1()
        {
            graphics = new GraphicsDeviceManager(this);
            Content.RootDirectory = "Content";
            TargetElapsedTime = TimeSpan.FromTicks(333333);
        }

        protected override void Initialize()
        {
            base.Initialize();
        }

        protected override void LoadContent()
        {
            spriteBatch = new SpriteBatch(GraphicsDevice);
            spriteFont = Content.Load<SpriteFont>("SpriteFont1");
        }

        protected override void UnloadContent()
        {
        }
        /// <summary>
        /// 输入完成回调方法
        /// </summary>
        /// <param name="result"></param>
        void keyboardCallback(IAsyncResult result)
        {
            string retval = Guide.EndShowKeyboardInput(result);

            if (retval != null)
            {
                sipResult = retval;
            }
        }

        protected override void Update(GameTime gameTime)
        {
            if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed)
                this.Exit();
            // Display the SIP
            TouchCollection touchCollection = TouchPanel.GetState();

            foreach (TouchLocation touch in touchCollection)
            {
                if (touch.State == TouchLocationState.Pressed)
                    if (!Guide.IsVisible)
                        //弹出软键盘输入框
                        Guide.BeginShowKeyboardInput(PlayerIndex.One, sipTitle, sipDescription,
                            sipResult, keyboardCallback, new object());
            }

            base.Update(gameTime);
        }

        protected override void Draw(GameTime gameTime)
        {
            GraphicsDevice.Clear(Color.CornflowerBlue);

            //绘制界面的文字
            spriteBatch.Begin();
            spriteBatch.DrawString(spriteFont, sipResult, new Vector2 { X = 50, Y = 200 }, Color.Black);
            spriteBatch.End();

            base.Draw(gameTime);
        }
    }
}