cocos中常用到的单例模式

#ifndef _MANAGER_H_
#define _MANAGER_H_
#include "cocos2d.h";
//包含敌机和子弹的头文件
#include "Bullet\Bullet.h";
#include "Enemy\EnemyBase.h";

USING_NS_CC;

//子弹和敌机管理器，做成单例
class Manager
{
public:
    static Manager * getInstance();
    static void Manager::freeInstance(void);
private:
    static Manager * m_manager;
    Manager();
    bool init();
public:
    //使用以下的方法定义了俩个容器，并且实现了get方法，一定要注意get的返回值，这个返回的是引用
    //官方建议容器最好不要在堆上分配内存空间，当我们在栈上分配内存空间的时候一定要传递引用，否则就出错了
    Vector<EnemyBase *> & getEnemyVector(){return m_enemyVector;};
    Vector<Bullet *> & getBulletVector(){return m_bulletVector;};
private:
    Vector<EnemyBase *> m_enemyVector;
    Vector<Bullet *> m_bulletVector;
};

#endif

#include "Manager.h"

Manager * Manager::m_manager = NULL;

//在构造函数的初始化列表中初始化数组
Manager::Manager() : m_enemyVector(),m_bulletVector()
{
}

Manager * Manager::getInstance()
{
    if(m_manager == NULL)
    {
        m_manager = new Manager();
    }

    return m_manager;
}

void Manager::freeInstance(void)
{
    if(m_manager != NULL)
    {
        delete m_manager;
        m_manager = NULL;
    }
}

//场景切换完毕调用
void MainGame::onEnterTransitionDidFinish()
{
    //必须先调用父类的函数
    Layer::onEnterTransitionDidFinish();
    //添加敌机，每秒添加一个
    this->schedule(SEL_SCHEDULE(MainGame::addEnemy),1.0f);
    //添加子弹,每0.08秒产生一颗子弹
    this->schedule(SEL_SCHEDULE(MainGame::addBullet),0.08f);
    //碰撞检测
    this->schedule(SEL_SCHEDULE(MainGame::isHitEnemy),0.016f);
}

//碰撞检测
void MainGame::isHitEnemy(float tm)
{

}

//添加子弹
void MainGame::addBullet(float tm)
{
    auto bullet = Bullet::create();
    bullet->initBullet("bullet1.png");
    auto point = Point(m_player->getPositionX(),
        m_player->getPositionY()+m_player->getContentSize().height/2+10);
    bullet->setPosition(point);

    this->addChild(bullet);
    //将子弹添加到管理器中
    auto & vector = Manager::getInstance()->getBulletVector();
    vector.pushBack(bullet);
    log("%d",vector.size());
}