1.编写T32.h

#ifndef __T32_H__

#define __T32_H__

#include "cocos2d.h"

USING_NS_CC;

#define winSize Director::getInstance()->getWinSize()

#define CCLog cocos2d::log

#endif

2.编写TBack.h

#ifndef __TBack_H__

#define __TBack_H__

#include "T32.h"

class TBack : public Layer

{

public:

CREATE_FUNC(TBack);

bool init();

};

#endif

3编写TBack.cpp

#include "TBack.h"

bool TBack::init()

{

Layer::init();

setLocalZOrder(100);

Menu* menu = Menu::create();

MenuItemImage* item = MenuItemImage::create("CloseNormal.png", "CloseSelected.png",

[](Ref*){

Director::getInstance()->popScene();

});

menu->addChild(item);

item->setPosition(winSize.width / 2 - item->getBoundingBox().size.width / 2,

item->getBoundingBox().size.height / 2 - winSize.height / 2);

addChild(menu);

return true;

}

4.编写T06Box2D.h

#ifndef __T06Box2D_H__

#define __T06Box2D_H__

#include "T32.h"

#include "Box2D/Box2D.h"

class T06Box2D : public Layer

{

public:

CREATE_FUNC(T06Box2D);

bool init();

b2World* _world;

b2Body* _bat;

void update(float);

};

#endif

5编写：T06Box2D.cpp

#include "T06Box2D.h"

#define PTM_RATIO 32.0f

bool T06Box2D::init()

{

Layer::init();

//创建世界,后面的-9.8表示向下的重力加速度为9.8

//b2Vec2 gravity(0,-9.8f);

//这个表示没有重力加速度

b2Vec2 gravity(0,0.0f);

_world = new b2World(gravity);

{

b2BodyDef def;

//这里是一个动态的body，默认是静态的body

def.type = b2_dynamicBody;

//设置位置，要转换成重力场中的位置要除以PTM_RATIO

def.position.Set(winSize.width / 2 / PTM_RATIO, winSize.height / 2 / PTM_RATIO);

b2Body* body = _world->CreateBody(&def);

//让body受力

body->SetLinearVelocity(b2Vec2(10,20));

//显示body的精灵

Sprite* sprite = Sprite::create("CloseNormal.png");

addChild(sprite);

sprite->setPosition(body->GetPosition().x*PTM_RATIO, body->GetPosition().y*PTM_RATIO);

//设置body的形状，让它和sprite相一致,是圆形的

b2CircleShape shape;

//设置半径

shape.m_radius = sprite->getContentSize().width / 2 / PTM_RATIO;

//后面的一个参数表示的是密度系数

b2Fixture* fixture = body->CreateFixture(&shape, 1.0f);

//设置摩擦系统

fixture->SetFriction(0.0f);

//弹性系数

fixture->SetRestitution(1.0f);

//关联body和精灵

body->SetUserData(sprite);

}

//加个地板

{

b2BodyDef def;

// def.position.Set(0, 0);

b2Body* body = _world->CreateBody(&def);

//设置边界类型的形状

b2EdgeShape shape;

//设置地板的开始点和结束点

shape.Set(b2Vec2(0, 0), b2Vec2(winSize.width / PTM_RATIO, 0));

b2Fixture* fixture = body->CreateFixture(&shape, 1.0f);

//设置摩擦系数

fixture->SetFriction(0.0f);

//设置弹性系数

fixture->SetRestitution(1.0f);

}

//加个天花板

{

b2BodyDef def;

def.position.Set(0, winSize.height / PTM_RATIO);

b2Body* body = _world->CreateBody(&def);

b2EdgeShape shape;

shape.Set(b2Vec2(0, 0), b2Vec2(winSize.width / PTM_RATIO, 0));

b2Fixture* fixture = body->CreateFixture(&shape, 1.0f);

//摩擦系统

fixture->SetFriction(0.0f);

//弹性系数

fixture->SetRestitution(1.0f);

}

//左挡板

{

b2BodyDef def;

//def.position.Set(0, winSize.height / PTM_RATIO);

b2Body* body = _world->CreateBody(&def);

b2EdgeShape shape;

shape.Set(b2Vec2(0, 0), b2Vec2(0, winSize.height / PTM_RATIO));

b2Fixture* fixture = body->CreateFixture(&shape, 1.0f);

fixture->SetFriction(0.0f); //摩擦系统

fixture->SetRestitution(1.0f); //弹性系数

}

//右挡板

{

b2BodyDef def;

def.position.Set(winSize.width / PTM_RATIO, 0);

b2Body* body = _world->CreateBody(&def);

b2EdgeShape shape;

shape.Set(b2Vec2(0, 0), b2Vec2(0, winSize.height / PTM_RATIO));

b2Fixture* fixture = body->CreateFixture(&shape, 1.0f);

//摩擦系数

fixture->SetFriction(0.0f);

//弹性系数

fixture->SetRestitution(1.0f);

}

//球拍

{

b2BodyDef def;

def.position.Set(winSize.width / 2 / PTM_RATIO, winSize.height / 4 / PTM_RATIO);

b2Body* body = _world->CreateBody(&def);

_bat = body;

Sprite* sprite = Sprite::create("bat.png");

body->SetUserData(sprite);

addChild(sprite);

sprite->setPosition(body->GetPosition().x*PTM_RATIO, body->GetPosition().y*PTM_RATIO);

Size batSize = Size(100,30);

Size content = sprite->getContentSize();

sprite->setScale(batSize.width / content.width, batSize.height / content.height);

b2PolygonShape shape;

shape.SetAsBox(batSize.width / 2 / PTM_RATIO, batSize.height / 2 / PTM_RATIO);

b2Fixture* fixture = body->CreateFixture(&shape, 1.0f);

//摩擦系统

fixture->SetFriction(0.0f);

//弹性系统

fixture->SetRestitution(1.0f);

//touch

EventListenerTouchOneByOne* ev = EventListenerTouchOneByOne::create();

ev->onTouchBegan = [](Touch*, Event*){return true; };

ev->onTouchMoved = [&](Touch* touch, Event*){

float dx = touch->getDelta().x / PTM_RATIO;

b2Vec2 pos = _bat->GetPosition();

pos.x += dx;

//下面的函数等价于setPosition()

_bat->SetTransform(pos, 0);

};

_eventDispatcher->addEventListenerWithSceneGraphPriority(ev, this);

}

scheduleUpdate();

return true;

}

void T06Box2D::update(float dt)

{

//时间在流逝

_world->Step(dt, 8, 1);

//遍历这个世界的body

b2Body* body = _world->GetBodyList();

while (body)

{

//设置body相关的精灵的位置

Sprite* sprite = (Sprite*)body->GetUserData();

if (sprite)

{

sprite->setPosition(body->GetPosition().x*PTM_RATIO, body->GetPosition().y*PTM_RATIO);

sprite->setRotation(body->GetAngle()*180.0 / M_PI);

}

body = body->GetNext();

}

}

6.编写TMenu.h

#ifndef __TMenu_H__

#define __TMenu_H__

#include "T32.h"

class TMenu : public Layer

{

public:

CREATE_FUNC(TMenu);

bool init();

bool TouchBegan(Touch*, Event*);

};

#endif

7. 编写：TMenu.cpp

#include "TMenu.h"

#include "TBack.h"

#include "T01CPP11.h"

#include "T02Vector.h"

#include "T03Map.h"

#include "T04Label.h"

#include "T06Box2D.h"

static const char* title[] = {

"T01CPP11",

"T02Vector",

"T03Map",

"T04Label",

"T06Box2D"

};

bool TMenu::init()

{

Layer::init();

Menu* menu = Menu::create();

addChild(menu);

for (int i = 0; i < sizeof(title) / sizeof(*title); ++i)

{

MenuItemFont* item = MenuItemFont::create(title[i], [](Ref* sender){

MenuItem* item = (MenuItem*)sender;

int i = item->getTag()-1000;

Layer* l = NULL;

if (title[i] == "T01CPP11")  l = T01CPP11::create();

if (title[i] == "T02Vector") l = T02Vector::create();

if (title[i] == "T03Map") l = T03Map::create();

if (title[i] == "T04Label") l = T04Label::create();

if (title[i] == "T06Box2D") l = T06Box2D::create();

if (l)

{

TBack* b = TBack::create();

Scene* s = Scene::create();

s->addChild(b);

s->addChild(l);

Director::getInstance()->pushScene(s);

}

});

menu->addChild(item);

item->setTag(1000 + i);

}

menu->alignItemsVertically();

// 触摸

auto ev = EventListenerTouchOneByOne::create();

#if 0

ev->onTouchBegan = [](Touch*, Event*){

return true;

};

#endif

//ev->onTouchBegan = std::bind(&TMenu::TouchBegan, this, std::placeholders::_1, std::placeholders::_2);

ev->onTouchBegan = CC_CALLBACK_2(TMenu::TouchBegan, this);

ev->onTouchMoved = [&](Touch* touch, Event*){

setPositionY(getPositionY() + touch->getDelta().y);

};

_eventDispatcher->addEventListenerWithSceneGraphPriority(ev, this);

return true;

}

bool TMenu::TouchBegan(/*TMEnu* this, */Touch*, Event*)

{

return true;

}

8.编写AppDelegate.cpp

#include "AppDelegate.h"

#include "TMenu.h"

#include "TBack.h"

USING_NS_CC;

AppDelegate::AppDelegate() {

}

AppDelegate::~AppDelegate()

{

}

bool AppDelegate::applicationDidFinishLaunching() {

// initialize director

auto director = Director::getInstance();

auto glview = director->getOpenGLView();

if(!glview) {

glview = GLView::create("My Game");

glview->setFrameSize(480, 320);

director->setOpenGLView(glview);

}

glview->setDesignResolutionSize(480, 320, ResolutionPolicy::EXACT_FIT);

// turn on display FPS

director->setDisplayStats(true);

// set FPS. the default value is 1.0/60 if you don't call this

director->setAnimationInterval(1.0 / 60);

// create a scene. it's an autorelease object

auto scene = Scene::create();

scene->addChild(TMenu::create());

scene->addChild(TBack::create());

// run

director->runWithScene(scene);

return true;

}

// This function will be called when the app is inactive. When comes a phone call,it's be invoked too

void AppDelegate::applicationDidEnterBackground() {

Director::getInstance()->stopAnimation();

// if you use SimpleAudioEngine, it must be pause

// SimpleAudioEngine::getInstance()->pauseBackgroundMusic();

}

// this function will be called when the app is active again

void AppDelegate::applicationWillEnterForeground() {

Director::getInstance()->startAnimation();

// if you use SimpleAudioEngine, it must resume here

// SimpleAudioEngine::getInstance()->resumeBackgroundMusic();

}

运行效果：