cocos2dx-3.10虚拟摇杆的实现

本篇文章是在cocos2dx-2.x的基础上改编而来，基本没有什么大的改变，只是让技术小白少走一些弯路。好了。下面就直接上代码了。
首先把虚拟摇杆封装成一个类，就要建立一个.cpp文件和.文件，这个文件就命名为HRocker.h文件。

其中HRocker.h的文件如下：

#ifndef HRocker_H
#define HRocker_H
#include "cocos2d.h"

using namespace cocos2d;

class HRocker :public Layer {
public:
	//初始化 aPoint是摇杆中心 aRadius是摇杆半径 aJsSprite是摇杆控制点 aJsBg是摇杆背景
	static HRocker*  HRockerWithCenter(Vec2 point, float Radius, Sprite* aJsSprite, Sprite* aJsBg, bool _isFollowRole);
	//启动摇杆
	void Active();
	//解除摇杆
	void Inactive();
	Vec2 getDirection();

private:
	EventListenerTouchOneByOne* touchListener;
	HRocker * initWithCenter(Vec2 point, float aRadius, Sprite* aJsSprite, Sprite* aJsBg, bool _isFollowRole);
	Vec2 centerPoint;//摇杆中心
	Vec2 currentPoint;//摇杆当前位置
	bool active;//是否激活摇杆
	float radius;//摇杆半径
	Sprite *jsSprite;
	bool isFollowRole;//是否跟随用户点击
	float getVelocity();
	void  updatePos(float dt);
	virtual bool onTouchBegan(Touch *pTouch, Event *pEvent);
	virtual void onTouchMoved(Touch *pTouch, Event *pEvent);
	virtual void onTouchEnded(Touch *pTouch, Event *pEvent);

	CREATE_FUNC(HRocker);
};

#endif

其下是HRockre.cpp中的内容

#include "HRocker.h"

using namespace cocos2d;

//定义一个计时器，随时检测鼠标点击的位置
void HRocker::updatePos(float dt){
	jsSprite->setPosition(ccpAdd(jsSprite->getPosition(), ccpMult(ccpSub(currentPoint, jsSprite->getPosition()), 0.5)));
}
//启动摇杆
void HRocker::Active()
{
	if (!active) {
		active = true;
		schedule(schedule_selector(HRocker::updatePos));//添加刷新函数
		//CCDirector::sharedDirector()->getTouchDispatcher()->addTargetedDelegate(this, 0, false);
		touchListener = EventListenerTouchOneByOne::create();
		touchListener->setSwallowTouches(true);

		touchListener->onTouchBegan = CC_CALLBACK_2(HRocker::onTouchBegan, this);
		touchListener->onTouchMoved = CC_CALLBACK_2(HRocker::onTouchMoved, this);
		touchListener->onTouchEnded = CC_CALLBACK_2(HRocker::onTouchEnded, this);
		// 注册事件监听机制
		_eventDispatcher->addEventListenerWithSceneGraphPriority(touchListener, this);

	}
	else {
	}
}
//解除摇杆
void   HRocker::Inactive()
{
	if (active) {
		active = false;
		this->unschedule(schedule_selector(HRocker::updatePos));//删除刷新
		_eventDispatcher->removeEventListener(touchListener);//删除委托
	}
	else {
	}
}
//摇杆方位
Vec2 HRocker::getDirection()
{

	return ccpNormalize(ccpSub(centerPoint, currentPoint));
}
//摇杆力度
float HRocker::getVelocity()
{
	return ccpDistance(centerPoint, currentPoint);
}
HRocker* HRocker::HRockerWithCenter(Vec2 point, float aRadius, Sprite* aJsSprite, Sprite* aJsBg, bool _isFollowRole){
	HRocker *jstick = HRocker::create();
	jstick->initWithCenter(point, aRadius, aJsSprite, aJsBg, _isFollowRole);
	return jstick;
}
bool HRocker::onTouchBegan(Touch* touch, Event* event)
{
	if (!active)
		return false;
	this->setVisible(true);
	Vec2 touchPoint = touch->getLocationInView();
	touchPoint = Director::sharedDirector()->convertToGL(touchPoint);
	if (!isFollowRole){
		if (ccpDistance(touchPoint, centerPoint) > radius){
			return false;
		}
	}
	currentPoint = touchPoint;
	if (isFollowRole){
		centerPoint = currentPoint;
		jsSprite->setPosition(currentPoint);
		this->getChildByTag(88)->setPosition(currentPoint);
	}
	return true;
}
void  HRocker::onTouchMoved(Touch* touch, Event* event)
{
	Vec2 touchPoint = touch->getLocationInView();
	touchPoint = Director::sharedDirector()->convertToGL(touchPoint);
	if (ccpDistance(touchPoint, centerPoint) > radius)
	{
		currentPoint = ccpAdd(centerPoint, ccpMult(ccpNormalize(ccpSub(touchPoint, centerPoint)), radius));
	}
	else {
		currentPoint = touchPoint;
	}
}
void  HRocker::onTouchEnded(Touch* touch, Event* event)
{
	currentPoint = centerPoint;
	if (isFollowRole){
		this->setVisible(false);
	}
}
HRocker* HRocker::initWithCenter(Vec2 aPoint, float aRadius, Sprite* aJsSprite, Sprite* aJsBg, bool _isFollowRole){
	isFollowRole = _isFollowRole;
	active = false;
	radius = aRadius;
	if (!_isFollowRole){
		centerPoint = aPoint;
	}
	else{
		centerPoint = ccp(0, 0);
	}
	currentPoint = centerPoint;
	jsSprite = aJsSprite;
	jsSprite->setPosition(centerPoint);
	aJsBg->setPosition(centerPoint);
	aJsBg->setTag(88);
	this->addChild(aJsBg);
	this->addChild(jsSprite);
	if (isFollowRole){
		this->setVisible(false);
	}
	this->Active();//激活摇杆
	return this;
}

好了，到这里一个虚拟摇杆的的类就完成了，接下来就是虚拟摇杆的精灵了
其中要看你把这个摇杆精灵放在哪个。cpp的文件当中了，我这个只是测试的例子，所以就放在
helloword.cpp文件当中。在init函数当中添加如下的代码就可以运行了。
其中要加上#include "HRocker.h"这个有文件
Sprite *spRocker2 = Sprite::create("rockerBar.png");//摇杆
    Sprite *spRockerBG2 = Sprite::create("rocker.png");//摇杆背景
    HRocker* rocker2 = HRocker::HRockerWithCenter(Vec2(210.0f, 130.0f), 50.0f, spRocker2, spRockerBG2, true);//创建摇杆
    this->addChild(rocker2);//摇杆添加到layer中 
这就是我通过cocos2dx-2.x修改过来的了，