从零开发游戏需要学习的c#模块，第三十四章（设置界面）
本节课学习目标
标题画面增加“设置”选项
设置界面：音量滑块、全屏开关
设置保存到 JSON 文件
暂停菜单中也能打开设置
第一步：扩展存档数据
打开SaveManager.cs，在SaveData类里加两个字段：
public class SaveData
{
public int HighScore { get; set; }
public int TotalCoinsCollected { get; set; }
public int TotalEnemiesDefeated { get; set; }
public float MusicVolume { get; set; } = 0.5f; // ★ 音量 0~1
public bool IsFullscreen { get; set; } = false; // ★ 是否全屏
}
第二步：创建设置界面类
右键项目 →添加→类，文件名SettingsMenu.cs：
using Microsoft.Xna.Framework; using Microsoft.Xna.Framework.Graphics; using Microsoft.Xna.Framework.Input; using FontStashSharp; using System.Collections.Generic; namespace MY_FIRST_GAME { public class SettingsMenu { private List<string> options; private int selectedIndex; private KeyboardState previousKeyboard; private KeyboardState currentKeyboard; private bool adjustingVolume; // 正在调节音量 public float Volume { get; set; } public bool IsFullscreen { get; set; } public SettingsMenu(float volume, bool isFullscreen) { Volume = volume; IsFullscreen = isFullscreen; options = new List<string> { "音量", "全屏", "返回" }; selectedIndex = 0; adjustingVolume = false; } // 返回值：-1=还在设置, 0=返回, 1=音量变化, 2=全屏切换 public int Update() { previousKeyboard = currentKeyboard; currentKeyboard = Keyboard.GetState(); if (adjustingVolume) { if (IsKeyJustPressed(Keys.Left) || IsKeyJustPressed(Keys.A)) { Volume = MathHelper.Max(0, Volume - 0.1f); return 1; } if (IsKeyJustPressed(Keys.Right) || IsKeyJustPressed(Keys.D)) { Volume = MathHelper.Min(1, Volume + 0.1f); return 1; } if (IsKeyJustPressed(Keys.Enter) || IsKeyJustPressed(Keys.Escape)) { adjustingVolume = false; } return -1; } if (IsKeyJustPressed(Keys.W) || IsKeyJustPressed(Keys.Up)) { selectedIndex--; if (selectedIndex < 0) selectedIndex = options.Count - 1; } if (IsKeyJustPressed(Keys.S) || IsKeyJustPressed(Keys.Down)) { selectedIndex++; if (selectedIndex >= options.Count) selectedIndex = 0; } if (IsKeyJustPressed(Keys.Enter) || IsKeyJustPressed(Keys.Space)) { switch (selectedIndex) { case 0: // 音量 adjustingVolume = true; break; case 1: // 全屏 IsFullscreen = !IsFullscreen; return 2; case 2: // 返回 return 0; } } if (IsKeyJustPressed(Keys.Escape)) return 0; return -1; } private bool IsKeyJustPressed(Keys key) { return currentKeyboard.IsKeyDown(key) && previousKeyboard.IsKeyUp(key); } public void Draw(SpriteBatch spriteBatch, SpriteFontBase font, GraphicsDevice device) { Texture2D overlay = new Texture2D(device, 1, 1); overlay.SetData(new[] { new Color(0, 0, 0, 200) }); spriteBatch.Draw(overlay, new Rectangle(0, 0, 800, 600), Color.White); string title = "- 设置 -"; Vector2 titleSize = font.MeasureString(title); spriteBatch.DrawString(font, title, new Vector2(400 - titleSize.X / 2, 100), Color.White); // 音量选项 Color volColor = (selectedIndex == 0) ? Color.Gold : Color.LightGray; string volText = (selectedIndex == 0) ? "> 音量 <" : " 音量 "; spriteBatch.DrawString(font, volText, new Vector2(400 - font.MeasureString(volText).X / 2, 200), volColor); // 音量条 DrawSlider(spriteBatch, device, 250, 230, 300, 20, Volume); // 音量数值 string volValue = $"{(int)(Volume * 100)}%"; spriteBatch.DrawString(font, volValue, new Vector2(560, 230), Color.White); // 全屏选项 Color fsColor = (selectedIndex == 1) ? Color.Gold : Color.LightGray; string fsText = (selectedIndex == 1) ? "> 全屏 <" : " 全屏 "; spriteBatch.DrawString(font, fsText, new Vector2(400 - font.MeasureString(fsText).X / 2, 300), fsColor); string fsValue = IsFullscreen ? "开" : "关"; spriteBatch.DrawString(font, fsValue, new Vector2(560, 300), IsFullscreen ? Color.LimeGreen : Color.Gray); // 返回选项 Color backColor = (selectedIndex == 2) ? Color.Gold : Color.LightGray; string backText = (selectedIndex == 2) ? "> 返回 <" : " 返回 "; spriteBatch.DrawString(font, backText, new Vector2(400 - font.MeasureString(backText).X / 2, 400), backColor); string hint = "↑↓ 选择 | 回车 确认 | ←→ 调节 | ESC 返回"; spriteBatch.DrawString(font, hint, new Vector2(400 - font.MeasureString(hint).X / 2, 500), Color.Gray); } private void DrawSlider(SpriteBatch spriteBatch, GraphicsDevice device, int x, int y, int width, int height, float value) { Texture2D pixel = new Texture2D(device, 1, 1); pixel.SetData(new[] { Color.White }); // 背景 spriteBatch.Draw(pixel, new Rectangle(x, y, width, height), Color.DarkSlateGray); // 边框 spriteBatch.Draw(pixel, new Rectangle(x, y, width, 2), Color.White); spriteBatch.Draw(pixel, new Rectangle(x, y + height - 2, width, 2), Color.White); spriteBatch.Draw(pixel, new Rectangle(x, y, 2, height), Color.White); spriteBatch.Draw(pixel, new Rectangle(x + width - 2, y, 2, height), Color.White); // 填充 int fillWidth = (int)((width - 4) * value); spriteBatch.Draw(pixel, new Rectangle(x + 2, y + 2, fillWidth, height - 4), Color.Gold); // 滑块 int sliderX = x + 2 + fillWidth - 5; spriteBatch.Draw(pixel, new Rectangle(sliderX, y - 4, 10, height + 8), Color.White); } public void Reset() { selectedIndex = 0; adjustingVolume = false; } } }第三步：改造Game1.cs
1. 添加字段：
csharp
private SettingsMenu settingsMenu = default!; private bool inSettings = false;
2. 在Initialize里创建设置菜单：
csharp
settingsMenu = new SettingsMenu(saveData.MusicVolume, saveData.IsFullscreen); // 应用保存的设置 ApplySettings();
3. 添加应用设置的方法：
csharp
private void ApplySettings() { SoundEffect.MasterVolume = saveData.MusicVolume; _graphics.IsFullScreen = saveData.IsFullscreen; _graphics.ApplyChanges(); }4. 在标题画面加“设置”选项：
把标题画面的空格触发改成菜单选择。简单做法：在Update的Title状态里加：
csharp
case SceneType.Title: if (keyboard.IsKeyDown(Keys.Enter)) { inSettings = true; settingsMenu = new SettingsMenu(saveData.MusicVolume, saveData.IsFullscreen); settingsMenu.Reset(); } if (keyboard.IsKeyDown(Keys.Space) && !inSettings) { // 开始游戏... } break;5. 处理设置更新：
在Update开头（暂停检查之后）加：
csharp
if (inSettings) { int result = settingsMenu.Update(); if (result == 1) // 音量变化 { saveData.MusicVolume = settingsMenu.Volume; SoundEffect.MasterVolume = settingsMenu.Volume; } else if (result == 2) // 全屏切换 { saveData.IsFullscreen = settingsMenu.IsFullscreen; _graphics.IsFullScreen = settingsMenu.IsFullscreen; _graphics.ApplyChanges(); } else if (result == 0) // 返回 { SaveManager.Save(saveData); inSettings = false; } }6. 在Draw里画设置界面：
在所有绘制之后加：
csharp
if (inSettings) { _spriteBatch.Begin(); settingsMenu.Draw(_spriteBatch, font, GraphicsDevice); _spriteBatch.End(); }本节课学习到此结束，我叫魔法阵维护师，关注我，下期更精彩！