Android 游戏开发 引擎AndEngine加载（游戏菜单）

　　package gongziba;

　　import javax.microedition.khronos.opengles.GL10;

　　import org.anddev.andengine.engine.Engine;
import org.anddev.andengine.engine.camera.Camera;
import org.anddev.andengine.engine.options.EngineOptions;
import org.anddev.andengine.engine.options.EngineOptions.ScreenOrientation;
import org.anddev.andengine.engine.options.resolutionpolicy.RatioResolutionPolicy;
import org.anddev.andengine.entity.scene.Scene;
import org.anddev.andenginnu.MenuScene;
import org.anddev.andenginnu.MenuScene.IOnMenuItemClickListener;
import org.anddev.andenginnu.animator.SlideMenuAnimator;
import org.anddev.andenginnu.item.IMenuItem;
import org.anddev.andenginnu.item.SpriteMenuItem;
import org.anddev.andenginnu.item.TextMenuItem;
import org.anddev.andenginnu.item.decorator.ColorMenuItemDecorator;
import org.anddev.andengine.entity.sprite.Sprite;
import org.anddev.andengine.entity.util.FPSLogger;
import org.anddev.andengine.opengl.font.Font;
import org.anddev.andengine.opengl.font.FontFactory;
import org.anddev.andengine.opengl.texture.Texture;
import org.anddev.andengine.opengl.texture.TextureOptions;
import org.anddev.andengine.opengl.texture.region.TextureRegion;
import org.anddev.andengine.opengl.texture.region.TextureRegionFactory;
import org.anddev.andengine.ui.activity.BaseGameActivity;

　　import android.graphics.Color;
import android.view.KeyEvent;
import android.widget.Toast;

　　public class MainMenuActivity extends
  BaseGameActivity implements
  IOnMenuItemClickListener {
 // ===========================================================
 // Constants
 // ===========================================================

　　private static final int CAMERA_WIDTH = 410;
 private static final int CAMERA_HEIGHT = 308;

　　protected static final int MENU_ABOUT = 0;
 protected static final int MENU_QUIT = MENU_ABOUT + 1;
 protected static final int MENU_PLAY = 100;
 protected static final int MENU_SCORES = MENU_PLAY + 1;
 protected static final int MENU_OPTIONS = MENU_SCORES + 1;
 protected static final int MENU_HELP = MENU_OPTIONS + 1;

　　// 照相机
 protected Camera mCamera;
 // 主镜头
 protected Scene mMainScene;
 // 菜单背景结构
 private Texture mMenuBackTexture;
 // 背景区域
 private TextureRegion mMenuBackTextureRegion;
 // 静态菜单镜头
 protected MenuScene mStaticMenuScene,
   mPopUpMenuScene;
 // 弹出结构、字体结构
 private Texture mPopUpTexture;
 private Texture mFontTexture;
 private Font mFont;
 // 菜单结构区域
 protected TextureRegion mPopUpAboutTextureRegion;
 protected TextureRegion mPopUpQuitTextureRegion;
 protected TextureRegion mMenuPlayTextureRegion;
 protected TextureRegion mMenuScoresTextureRegion;
 protected TextureRegion mMenuOptionsTextureRegion;
 protected TextureRegion mMenuHelpTextureRegion;
 // 弹出
 private boolean popupDisplayed;

　　// 加载引擎场景
 @Override
 public Engine onLoadEngine() {
  // 与加载图片一致
  this.mCamera = new Camera(0, 0,
    CAMERA_WIDTH,
    CAMERA_HEIGHT);
  return new Engine(
    new EngineOptions(
      true,
      // 横屏设置
      ScreenOrientation.LANDSCAPE,
      new RatioResolutionPolicy(
        CAMERA_WIDTH,
        CAMERA_HEIGHT),
      this.mCamera));
 }

　　// 加载资源
 @Override
 public void onLoadResources() {
  /* Load Font/Textures. */
  this.mFontTexture = new Texture(
    256,
    256,
    // 结构选项设置
    TextureOptions.BILINEAR_PREMULTIPLYALPHA);
  // 字体存放位置
  FontFactory
    .setAssetBasePath("gfx/font/");
  // 获取字体
  this.mFont = FontFactory
    .createFromAsset(
      this.mFontTexture,
      this,
      "Flubber.ttf",
      32, true,
      Color.WHITE);
  // 加载引擎管理结构
  this.mEngine
    .getTextureManager()
    .loadTexture(
      this.mFontTexture);
  this.mEngine.getFontManager()
    .loadFont(this.mFont);
  // 菜单背景
  this.mMenuBackTexture = new Texture(
    512,
    512,
    TextureOptions.BILINEAR_PREMULTIPLYALPHA);
  // 菜单背景区域 取得存放的资源
  this.mMenuBackTextureRegion = TextureRegionFactory
    .createFromAsset(
      this.mMenuBackTexture,
      this,
      "gfx/icon.jpg",
      0, 0);
  this.mEngine
    .getTextureManager()
    .loadTexture(
      this.mMenuBackTexture);
  // 弹出结构
  this.mPopUpTexture = new Texture(
    512,
    512,
    TextureOptions.BILINEAR_PREMULTIPLYALPHA);
  // 按菜单按钮弹出关于 图片
  this.mPopUpAboutTextureRegion = TextureRegionFactory
    .createFromAsset(
      this.mPopUpTexture,
      this,
      "gfx/MainMenu/About_button.png",
      0, 0);
  // 按菜单按钮弹出退出 图片
  this.mPopUpQuitTextureRegion = TextureRegionFactory
    .createFromAsset(
      this.mPopUpTexture,
      this,
      "gfx/MainMenu/Quit_button.png",
      0, 50);
  this.mEngine
    .getTextureManager()
    .loadTexture(
      this.mPopUpTexture);
  // 弹出设置为false
  popupDisplayed = false;
 }

　　// 加载镜头
 @Override
 public Scene onLoadScene() {
  // 注册更新线程
  // import org.anddev.andengine.entity.util.FPSLogger;
  this.mEngine
    .registerUpdateHandler(new FPSLogger());
  // 静态菜单和弹出菜单方法
  this.createStaticMenuScene();
  this.createPopUpMenuScene();

　　// 菜单设置到屏幕中心
  final int centerX = (CAMERA_WIDTH - this.mMenuBackTextureRegion
    .getWidth()) / 2;
  final int centerY = (CAMERA_HEIGHT - this.mMenuBackTextureRegion
    .getHeight()) / 2;

　　this.mMainScene = new Scene(1);
  // 增加精灵和静态菜单
  final Sprite menuBack = new Sprite(
    centerX,
    centerY,
    this.mMenuBackTextureRegion);
  mMainScene.getLastChild()
    .attachChild(menuBack);
  mMainScene
    .setChildScene(mStaticMenuScene);

　　return this.mMainScene;
 }

　　@Override
 public void onLoadComplete() {
 }

　　// 菜单按钮按下事件
 @Override
 public boolean onKeyDown(
   final int pKeyCode,
   final KeyEvent pEvent) {
  if (pKeyCode == KeyEvent.KEYCODE_MENU
    && pEvent.getAction() == KeyEvent.ACTION_DOWN) {
   if (popupDisplayed) {
    // 移除以及重新设置
    this.mPopUpMenuScene
      .back();
    // 朱场景设置子场景到静态场景
    mMainScene
      .setChildScene(mStaticMenuScene);
    popupDisplayed = false;
   } else {
    /* Attach the menu. */
    this.mMainScene
      .setChildScene(
        this.mPopUpMenuScene,
        false,
        true,
        true);
    popupDisplayed = true;
   }
   return true;
  } else {
   return super.onKeyDown(
     pKeyCode, pEvent);
  }
 }

　　@Override
 public boolean onMenuItemClicked(
   final MenuScene pMenuScene,
   final IMenuItem pMenuItem,
   final float pMenuItemLocalX,
   final float pMenuItemLocalY) {
  switch (pMenuItem.getID()) {
  case MENU_ABOUT:
   Toast.makeText(
     MainMenuActivity.this,
     "关于",
     Toast.LENGTH_SHORT)
     .show();
   return true;
  case MENU_QUIT:

　　this.finish();
   return true;
  case MENU_PLAY:
   Toast.makeText(
     MainMenuActivity.this,
     "开始",
     Toast.LENGTH_SHORT)
     .show();
   return true;
  case MENU_SCORES:
   Toast.makeText(
     MainMenuActivity.this,
     "分数",
     Toast.LENGTH_SHORT)
     .show();
   return true;
  case MENU_OPTIONS:
   Toast.makeText(
     MainMenuActivity.this,
     "选项",
     Toast.LENGTH_SHORT)
     .show();
   return true;
  case MENU_HELP:
   Toast.makeText(
     MainMenuActivity.this,
     "Help selected",
     Toast.LENGTH_SHORT)
     .show();
   return true;
  default:
   return false;
  }
 }

　　// 静态菜单方法

　　protected void createStaticMenuScene() {
  this.mStaticMenuScene = new MenuScene(
    this.mCamera);

　　final IMenuItem playMenuItem = new ColorMenuItemDecorator(
    new TextMenuItem(
      MENU_PLAY,
      mFont, "开始游戏"),
    0.5f, 0.5f, 0.5f, 1.0f,
    0.0f, 0.0f);
  playMenuItem
    .setBlendFunction(
      GL10.GL_SRC_ALPHA,
      GL10.GL_ONE_MINUS_SRC_ALPHA);
  this.mStaticMenuScene
    .addMenuItem(playMenuItem);

　　final IMenuItem scoresMenuItem = new ColorMenuItemDecorator(
    new TextMenuItem(
      MENU_SCORES,
      mFont, "分数"),
    0.5f, 0.5f, 0.5f, 1.0f,
    0.0f, 0.0f);
  scoresMenuItem
    .setBlendFunction(
      GL10.GL_SRC_ALPHA,
      GL10.GL_ONE_MINUS_SRC_ALPHA);
  this.mStaticMenuScene
    .addMenuItem(scoresMenuItem);

　　final IMenuItem optionsMenuItem = new ColorMenuItemDecorator(
    new TextMenuItem(
      MENU_OPTIONS,
      mFont, "选项"),
    0.5f, 0.5f, 0.5f, 1.0f,
    0.0f, 0.0f);
  optionsMenuItem
    .setBlendFunction(
      GL10.GL_SRC_ALPHA,
      GL10.GL_ONE_MINUS_SRC_ALPHA);
  this.mStaticMenuScene
    .addMenuItem(optionsMenuItem);

　　final IMenuItem helpMenuItem = new ColorMenuItemDecorator(
    new TextMenuItem(
      MENU_HELP,
      mFont, "帮助"),
    0.5f, 0.5f, 0.5f, 1.0f,
    0.0f, 0.0f);
  helpMenuItem
    .setBlendFunction(
      GL10.GL_SRC_ALPHA,
      GL10.GL_ONE_MINUS_SRC_ALPHA);
  this.mStaticMenuScene
    .addMenuItem(helpMenuItem);
  this.mStaticMenuScene
    .buildAnimations();

　　this.mStaticMenuScene
    .setBackgroundEnabled(false);

　　this.mStaticMenuScene
    .setOnMenuItemClickListener(this);
 }
 
 //创建弹出按钮镜头
 protected void createPopUpMenuScene() {
  this.mPopUpMenuScene = new MenuScene(
    this.mCamera);

　　final SpriteMenuItem aboutMenuItem = new SpriteMenuItem(
    MENU_ABOUT,
    this.mPopUpAboutTextureRegion);
  aboutMenuItem
    .setBlendFunction(
      GL10.GL_SRC_ALPHA,
      GL10.GL_ONE_MINUS_SRC_ALPHA);
  this.mPopUpMenuScene
    .addMenuItem(aboutMenuItem);

　　final SpriteMenuItem quitMenuItem = new SpriteMenuItem(
    MENU_QUIT,
    this.mPopUpQuitTextureRegion);
  quitMenuItem
    .setBlendFunction(
      GL10.GL_SRC_ALPHA,
      GL10.GL_ONE_MINUS_SRC_ALPHA);
  this.mPopUpMenuScene
    .addMenuItem(quitMenuItem);
  this.mPopUpMenuScene
    .setMenuAnimator(new SlideMenuAnimator());

　　this.mPopUpMenuScene
    .buildAnimations();

　　this.mPopUpMenuScene
    .setBackgroundEnabled(false);

　　this.mPopUpMenuScene
    .setOnMenuItemClickListener(this);
 }

　　}