Cocos2d-x3.2 Loading场景的设计

//GameScene.h

#include "cocos2d.h"

USING_NS_CC;

class GameScene : public cocos2d::Layer
{
public:
    static Scene* createScene();
    
    virtual bool init();
    
    void menuCallback(Ref* pSender);
    
    void loadingCallBack(Ref* pSender);
    
    void turnToHelloScene();
    
private:
    Size size;
    Label *labelLoading;      //Loading字样
    Label *labelPercent;      //进度条数字
    
    int numberOfSprites;    //需要加载的资源数目
    int numberOfLoadSprites;    //已经加载完的资源数目
    
    ProgressTimer *loadProgress;      //进度条
    
    CREATE_FUNC(GameScene);
};

//GameScene.cpp

#include "GameScene.h"
#include "HelloWorldScene.h"

USING_NS_CC;

cocos2d::Scene* GameScene::createScene()
{
    auto scene = Scene::create();   //创建一个场景
    auto layer = GameScene::create();   //创建一个图层
    scene->addChild(layer);
    return scene;
}

//初始化当前的图层
bool GameScene::init()
{
    if(!Layer::init())      //初始化父类
        return false;
    
    //获取屏幕大小
    size = Director::getInstance()->getVisibleSize();
    //size = Director::getInstance()->getWinSize();
    
    labelLoading = Label::createWithSystemFont("Loading...", "Marker Felt", 50);
    labelLoading->setPosition(Vec2(size.width/2, size.height/2));
    this->addChild(labelLoading);
    
    labelPercent = Label::createWithSystemFont("%0", "Marker Felt", 50);
    labelPercent->setPosition(Vec2(size.width/2, size.height*0.3));
    this->addChild(labelPercent);
    
    numberOfSprites = 200;
    numberOfLoadSprites = 0;
    
    //创建一个进度条
    loadProgress = ProgressTimer::create(Sprite::create("sliderProgress.png"));
    loadProgress->setBarChangeRate(Vec2(1, 0));     //横向移动
    loadProgress->setType(ProgressTimer::Type::BAR);
    loadProgress->setMidpoint(Vec2(0, 0));
    loadProgress->setPosition(Vec2(size.width/2, size.height*0.2));
    loadProgress->setPercentage(0.0f);
    this->addChild(loadProgress, 1);
    
    //加载资源，由于图片过少，进度条速度过快，这里让其加载图片多一些，总共200张
    for (int i=0; i<100; i++)
    {
        Director::getInstance()->getTextureCache()->addImageAsync("OnePiece_1.png", CC_CALLBACK_1(GameScene::loadingCallBack, this));
        Director::getInstance()->getTextureCache()->addImageAsync("Flag_1.png", CC_CALLBACK_1(GameScene::loadingCallBack, this));
    }
    
    return true;
}

void GameScene::loadingCallBack(Ref* pSender)
{
    numberOfLoadSprites++;
    
    char tmp[10];
    float value = ((float)numberOfLoadSprites / numberOfSprites)*100;   //已加载的百分比
    sprintf(tmp, "%d%%", (int)(value));
    labelPercent->setString(tmp);
    
    loadProgress->setPercentage(value);
    
    //加载完成，切换场景
    if (numberOfLoadSprites == numberOfSprites) {
        turnToHelloScene();
    }
}

void GameScene::turnToHelloScene()
{
    //读完进度条后跳转到HelloWorld场景
    Director::getInstance()->replaceScene(HelloWorld::createScene());
}

Cocos2d-x3.2 Loading场景的设计