《Cocos 游戏开发实战》5.1 启动流程与首屏

import { _decorator, Component, director, game, Game, sys, view, ResolutionPolicy } from 'cc';
const { ccclass } = _decorator;

@ccclass('AppEntry')
export class AppEntry extends Component {
  onLoad(): void {
    // 设计分辨率在工程里锁死为 960×540，这里显式再设一次，
    // 保证在编辑器预览与真机上取到的是同一套可见尺寸
    view.setDesignResolutionSize(960, 540, ResolutionPolicy.SHOW_ALL);

    // 小游戏切后台会冻结定时器，回前台必须重新对时，
    // 这里先注册好，避免玩法层再各自注册一遍
    game.on(Game.EVENT_SHOW, this.onShow, this);
    game.on(Game.EVENT_HIDE, this.onHide, this);

    // 记录冷启动时刻，供 15.3 的启动耗时统计使用
    this.bootAt = game.totalTime;
  }

  private bootAt = 0;

  private onShow(): void {
    // 回前台：交回给常驻的游戏状态管理器（见 5.3）
  }

  private onHide(): void {
    // 切后台：暂停音频、落盘存档（见 5.3）
  }
}

[
  { "__type__": "cc.SceneAsset", "_name": "boot", "scene": { "__id__": 1 } },
  {
    "__type__": "cc.Scene",
    "_name": "boot",
    "_children": [ { "__id__": 2 } ],
    "_globals": { "__id__": 9 }
  },
  {
    "__type__": "cc.Node",
    "_name": "Canvas",
    "_parent": { "__id__": 1 },
    "_components": [ { "__id__": 3 }, { "__id__": 4 }, { "__id__": 5 } ],
    "_children": [ { "__id__": 6 }, { "__id__": 7 } ]
  },
  { "__type__": "cc.UITransform", "node": { "__id__": 2 }, "_contentSize": { "width": 960, "height": 540 } },
  { "__type__": "cc.Canvas", "node": { "__id__": 2 }, "_cameraComponent": { "__id__": 8 } },
  { "__type__": "cc.Widget", "node": { "__id__": 2 } },
  { "__type__": "cc.Node", "_name": "ProgressBar", "_parent": { "__id__": 2 } },
  { "__type__": "cc.Node", "_name": "VersionLabel", "_parent": { "__id__": 2 } },
  { "__type__": "cc.Camera", "node": { "__id__": 8 }, "_projection": 0 }
]

import {
  _decorator, Component, director, assetManager, resources, JsonAsset,
  ProgressBar, Label, sys,
} from 'cc';
const { ccclass, property } = _decorator;

interface BootStep {
  readonly name: string;
  readonly weight: number;
  run(done: (ok: boolean) => void): void;
}

@ccclass('BootFlow')
export class BootFlow extends Component {
  @property(ProgressBar) bar: ProgressBar | null = null;
  @property(Label) tip: Label | null = null;

  private steps: BootStep[] = [];
  private totalWeight = 0;
  private finishedWeight = 0;

  onLoad(): void {
    this.steps = [
      { name: 'configs', weight: 2, run: (d) => this.loadConfigs(d) },
      { name: 'bundle', weight: 5, run: (d) => this.loadLevelBundle(d) },
      { name: 'home', weight: 3, run: (d) => this.preloadHome(d) },
    ];
    this.totalWeight = this.steps.reduce((s, x) => s + x.weight, 0);
    this.runNext(0);
  }

  private runNext(i: number): void {
    if (i >= this.steps.length) {
      this.finish();
      return;
    }
    const step = this.steps[i];
    this.setTip(step.name);
    step.run((ok) => {
      if (!ok) {
        this.setTip('加载失败，请检查网络后重试');
        return;
      }
      this.finishedWeight += step.weight;
      this.paint(this.finishedWeight / this.totalWeight);
      this.runNext(i + 1);
    });
  }

  private loadConfigs(done: (ok: boolean) => void): void {
    resources.load('configs/levels', JsonAsset, (err, asset) => {
      if (err !== null || asset === null) {
        done(false);
        return;
      }
      done(true);
    });
  }

  private loadLevelBundle(done: (ok: boolean) => void): void {
    assetManager.loadBundle('bundle-levels', (err, bundle) => {
      done(err === null && bundle !== null);
    });
  }

  private preloadHome(done: (ok: boolean) => void): void {
    resources.preloadDir('textures/home', () => done(true));
  }

  private paint(ratio: number): void {
    if (this.bar !== null) this.bar.progress = ratio;
  }

  private setTip(text: string): void {
    if (this.tip !== null) this.tip.string = text;
  }

  private finish(): void {
    // 到这一步首包资源已就位，切主场景不会再有可感知的等待
    director.loadScene('main', (err) => {
      if (err !== null) {
        console.error('[BootFlow] 进入主场景失败', err);
      }
    });
  }
}

// src/core/boot-progress.ts —— 与引擎无关，可直接单测
export interface WeightedStep {
  readonly name: string;
  readonly weight: number;
}

export class BootProgress {
  private readonly total: number;
  private done = 0;
  private last = 0;

  constructor(steps: readonly WeightedStep[]) {
    this.total = steps.reduce((s, x) => s + x.weight, 0);
  }

  /** 完成一步，返回 [0, 1] 的进度；保证单调不减 */
  complete(weight: number): number {
    this.done += weight;
    const raw = this.total === 0 ? 1 : this.done / this.total;
    this.last = Math.max(this.last, Math.min(1, raw));
    return this.last;
  }

  get ratio(): number {
    return this.last;
  }
}

// src/platform/storage.ts —— 存档键与后端选择
import { sys } from 'cc';

export const SAVE_KEY = 'block-dash.save.v1';

export function readSave(): string | null {
  if (sys.platform === sys.Platform.WECHAT_GAME) {
    // 微信端在 SDK 适配层里换成 wx.getStorageSync
    return sys.localStorage.getItem(SAVE_KEY);
  }
  return sys.localStorage.getItem(SAVE_KEY);
}