Cocos2d-x 触摸响应事件CCTouchDelegate

刚开始接触Cocos2d-x，一边看书，一边看官方Demo的代码，在SpriteTest中，有个函数ccTouchesEnded(...)功能类似VC里面LeftButtonUp（...），刚开始以为这是自定义的函数实现，后来打开demo在屏幕上操作，发现这是个响应事件，然后去找基类，看有没有这个函数，然后就发现了这么个玩意。class CC_DLL CCLayer : public
CCNode, public CCTouchDelegate, public CCAccelerometerDelegate, public CCKeypadDelegate{...};

void Sprite1::ccTouchesEnded(CCSet* touches, CCEvent* event)
{
CCSetIterator it;
CCTouch* touch;

for( it = touches->begin(); it != touches->end(); it++)
{
touch = (CCTouch*)(*it);

if(!touch)
break;

CCPoint location = touch->getLocation();

addNewSpriteWithCoords( location );
}
}

后面发现这个跟VC里面鼠标响应事件一个原理，就查询资料，继续加强对这个触摸类的理解和使用。

1.要想使得该布景层有这种触摸响应,要进行游戏交互，就得先在构造函数中 setTouchEnabled( true );

2.了解一下相关的几个类

CCTouch：它封装了触摸点，可以通过locationInView函数返回一个CCPoint。

CCTouchDelegate：它是触摸事件委托，就是系统捕捉到触摸事件后交由它或者它的子类处理，所以我们在处理触屏事件时，必须得继承它。它封装了下面这些处理触屏事件的函数：

virtualboolcc<span style="color:#ff0000;">Touch</span>Began(CCTouch
*pTouch, CCEvent *pEvent);
virtualvoidccTouchMoved(CCTouch
*pTouch, CCEvent *pEvent);
virtualvoidccTouchEnded(CCTouch
*pTouch, CCEvent *pEvent);
virtualvoidccTouchCancelled(CCTouch
*pTouch, CCEvent *pEvent);

virtualvoidcc<span style="color:#ff0000;">Touches</span>Began(CCSet
*pTouches, CCEvent *pEvent);
virtualvoidccTouchesMoved(CCSet
*pTouches, CCEvent *pEvent);
virtualvoidccTouchesEnded(CCSet
*pTouches, CCEvent *pEvent);
virtualvoidccTouchesCancelled(CCSet
*pTouches, CCEvent *pEvent);

ccTouchesCancelled和ccTouchCancelled函数很少用，在接到系统中断通知，需要取消触摸事件的时候才会调用此方法。如：应用长时间无响应、当前view从window上移除、触摸的时候来电话了等。

CCTargetedTouchDelegate和CCStandardTouchDelegate是CCTouchDelegate的子类，类结构图如下：



CCStandardTouchDelegate用于处理多点触摸;CCTargetedTouchDelegate用于处理单点触摸。

CCTouchDispatcher：实现触摸事件分发，它封装了下面这两个函数，可以把CCStandardTouchDelegate和CCTargetedTouchDelegate添加到分发列表中：

void addStandardDelegate(CCTouchDelegate *pDelegate, intnPriority);

void addTargetedDelegate(CCTouchDelegate *pDelegate, intnPriority,boolbSwallowsTouches);

CCTouchHandler：封装了CCTouchDelegate和其对应的优先级，优先级越高，分发的时候越容易获得事件处理权，CCStandardTouchHandler和CCTargetedTouchHandler是它的子类。

3.处理触屏事件时操作和执行的流程

用户自定义类继承CCTouchDelegate，重写触屏事件处理函数和registerWithTouchDispatcher函数，在init或者onEnter函数中调用registerWithTouchDispatcher函数，如：

(1.)定义类

class CCGameLayer : public CCNode, public CCTouchDelegate, public CCAccelerometerDelegate, public CCKeypadDelegate
{
public:
CCGameLayer();
virtual ~CCGameLayer();
bool init();

CC_DEPRECATED_ATTRIBUTE static CCGameLayer *node(void);
static CCGameLayer *create(void);

virtual void onEnter();
virtual void onExit();
virtual void onEnterTransitionDidFinish();

// default implements are used to call script callback if exist
virtual bool ccTouchBegan(CCTouch *pTouch, CCEvent *pEvent);
virtual void ccTouchMoved(CCTouch *pTouch, CCEvent *pEvent);
virtual void ccTouchEnded(CCTouch *pTouch, CCEvent *pEvent);
virtual void ccTouchCancelled(CCTouch *pTouch, CCEvent *pEvent);

// default implements are used to call script callback if exist
virtual void ccTouchesBegan(CCSet *pTouches, CCEvent *pEvent);
virtual void ccTouchesMoved(CCSet *pTouches, CCEvent *pEvent);
virtual void ccTouchesEnded(CCSet *pTouches, CCEvent *pEvent);
virtual void ccTouchesCancelled(CCSet *pTouches, CCEvent *pEvent);

virtual void didAccelerate(CCAcceleration* pAccelerationValue);
virtual void registerWithTouchDispatcher(void);
};

(2.)registerWithTouchDispatcher函数实现

void CCGameLayer::registerWithTouchDispatcher()
{
cocos2d::CCTouchDispatcher::sharedDispatcher()->addTargetedDelegate(this,
0, true);
}

(3.)在init或者OnEnter中调用

void CCGameLayer::onEnter()
{
CCDirector* pDirector = CCDirector::sharedDirector();
if (m_bIsTouchEnabled)
{
<span style="color:#ff0000;">this->registerWithTouchDispatcher();
</span>    }

CCNode::onEnter();

if (m_bIsAccelerometerEnabled)
{
pDirector->getAccelerometer()->setDelegate(this);
}

if (m_bIsKeypadEnabled)
{
pDirector->getKeypadDispatcher()->addDelegate(this);
}
}

(4.)追踪解析

appdelegate.cpp

CCDirector *pDirector = CCDirector::sharedDirector();
pDirector->setOpenGLView(CCEGLView::sharedOpenGLView());

CCSize screenSize = CCEGLView::sharedOpenGLView()->getFrameSize();

跟进getFrameSize()函数，发现了：

LRESULT CCEGLView::WindowProc(UINT message, WPARAM wParam, LPARAM lParam)

这下就明白了，其实最终接受处理跟VC一样，只不过cocos2d-x封装了以下，以下是WindowProc(...)的实现代码：

LRESULT CCEGLView::WindowProc(UINT message, WPARAM wParam, LPARAM lParam)
{
BOOL bProcessed = FALSE;

switch (message)
{
case <span style="color:#ff0000;">WM_LBUTTONDOWN</span>:
#if(_MSC_VER >= 1600)
// Don't process message generated by Windows Touch
if (m_bSupportTouch && (s_pfGetMessageExtraInfoFunction() & MOUSEEVENTF_FROMTOUCH) == MOUSEEVENTF_FROMTOUCH) break;
#endif /* #if(_MSC_VER >= 1600) */

if (m_pDelegate && MK_LBUTTON == wParam)
{
POINT point = {(short)LOWORD(lParam), (short)HIWORD(lParam)};
CCPoint pt(point.x, point.y);
pt.x /= m_fFrameZoomFactor;
pt.y /= m_fFrameZoomFactor;
CCPoint tmp = ccp(pt.x, m_obScreenSize.height - pt.y);
if (m_obViewPortRect.equals(CCRectZero) || m_obViewPortRect.containsPoint(tmp))
{
m_bCaptured = true;
SetCapture(m_hWnd);
int id = 0;
handleTouchesBegin(1, &id, &pt.x, &pt.y);
}
}
break;

case WM_MOUSEMOVE:
#if(_MSC_VER >= 1600)
// Don't process message generated by Windows Touch
if (m_bSupportTouch && (s_pfGetMessageExtraInfoFunction() & MOUSEEVENTF_FROMTOUCH) == MOUSEEVENTF_FROMTOUCH) break;
#endif /* #if(_MSC_VER >= 1600) */
if (MK_LBUTTON == wParam && m_bCaptured)
{
POINT point = {(short)LOWORD(lParam), (short)HIWORD(lParam)};
CCPoint pt(point.x, point.y);
int id = 0;
pt.x /= m_fFrameZoomFactor;
pt.y /= m_fFrameZoomFactor;
handleTouchesMove(1, &id, &pt.x, &pt.y);
}
break;

case WM_LBUTTONUP:
#if(_MSC_VER >= 1600)
// Don't process message generated by Windows Touch
if (m_bSupportTouch && (s_pfGetMessageExtraInfoFunction() & MOUSEEVENTF_FROMTOUCH) == MOUSEEVENTF_FROMTOUCH) break;
#endif /* #if(_MSC_VER >= 1600) */
if (m_bCaptured)
{
POINT point = {(short)LOWORD(lParam), (short)HIWORD(lParam)};
CCPoint pt(point.x, point.y);
int id = 0;
pt.x /= m_fFrameZoomFactor;
pt.y /= m_fFrameZoomFactor;
handleTouchesEnd(1, &id, &pt.x, &pt.y);

ReleaseCapture();
m_bCaptured = false;
}
break;
#if(_MSC_VER >= 1600)
case <span style="color:#ff0000;">WM_TOUCH</span>:
{
BOOL bHandled = FALSE;
UINT cInputs = LOWORD(wParam);
PTOUCHINPUT pInputs = new TOUCHINPUT[cInputs];
if (pInputs)
{
if (s_pfGetTouchInputInfoFunction((HTOUCHINPUT)lParam, cInputs, pInputs, sizeof(TOUCHINPUT)))
{
for (UINT i=0; i < cInputs; i++)
{
TOUCHINPUT ti = pInputs[i];
POINT input;
input.x = TOUCH_COORD_TO_PIXEL(ti.x);
input.y = TOUCH_COORD_TO_PIXEL(ti.y);
ScreenToClient(m_hWnd, &input);
CCPoint pt(input.x, input.y);
CCPoint tmp = ccp(pt.x, m_obScreenSize.height - pt.y);
if (m_obViewPortRect.equals(CCRectZero) || m_obViewPortRect.containsPoint(tmp))
{
pt.x /= m_fFrameZoomFactor;
pt.y /= m_fFrameZoomFactor;

if (ti.dwFlags & TOUCHEVENTF_DOWN)
handleTouchesBegin(1, reinterpret_cast<int*>(&ti.dwID), &pt.x, &pt.y);
else if (ti.dwFlags & TOUCHEVENTF_MOVE)
handleTouchesMove(1, reinterpret_cast<int*>(&ti.dwID), &pt.x, &pt.y);
else if (ti.dwFlags & TOUCHEVENTF_UP)
handleTouchesEnd(1, reinterpret_cast<int*>(&ti.dwID), &pt.x, &pt.y);
}
}
bHandled = TRUE;
}
delete [] pInputs;
}
if (bHandled)
{
s_pfCloseTouchInputHandleFunction((HTOUCHINPUT)lParam);
}
}
break;
#endif /* #if(_MSC_VER >= 1600) */
case WM_SIZE:
switch (wParam)
{
case SIZE_RESTORED:
CCApplication::sharedApplication()->applicationWillEnterForeground();
break;
case SIZE_MINIMIZED:
CCApplication::sharedApplication()->applicationDidEnterBackground();
break;
}
break;
case WM_KEYDOWN:
if (wParam == VK_F1 || wParam == VK_F2)
{
CCDirector* pDirector = CCDirector::sharedDirector();
if (GetKeyState(VK_LSHIFT) < 0 ||  GetKeyState(VK_RSHIFT) < 0 || GetKeyState(VK_SHIFT) < 0)
pDirector->getKeypadDispatcher()->dispatchKeypadMSG(wParam == VK_F1 ? kTypeBackClicked : kTypeMenuClicked);
}
if ( m_lpfnAccelerometerKeyHook!=NULL )
{
(*m_lpfnAccelerometerKeyHook)( message,wParam,lParam );
}
break;
case WM_KEYUP:
if ( m_lpfnAccelerometerKeyHook!=NULL )
{
(*m_lpfnAccelerometerKeyHook)( message,wParam,lParam );
}
break;
case WM_CHAR:
{
if (wParam < 0x20)
{
if (VK_BACK == wParam)
{
CCIMEDispatcher::sharedDispatcher()->dispatchDeleteBackward();
}
else if (VK_RETURN == wParam)
{
CCIMEDispatcher::sharedDispatcher()->dispatchInsertText("\n", 1);
}
else if (VK_TAB == wParam)
{
// tab input
}
else if (VK_ESCAPE == wParam)
{
// ESC input
//CCDirector::sharedDirector()->end();
}
}
else if (wParam < 128)
{
// ascii char
CCIMEDispatcher::sharedDispatcher()->dispatchInsertText((const char *)&wParam, 1);
}
else
{
char szUtf8[8] = {0};
int nLen = WideCharToMultiByte(CP_UTF8, 0, (LPCWSTR)&wParam, 1, szUtf8, sizeof(szUtf8), NULL, NULL);
CCIMEDispatcher::sharedDispatcher()->dispatchInsertText(szUtf8, nLen);
}
if ( m_lpfnAccelerometerKeyHook!=NULL )
{
(*m_lpfnAccelerometerKeyHook)( message,wParam,lParam );
}
}
break;
case <span style="color:#ff0000;">WM_PAINT</span>:
PAINTSTRUCT ps;
BeginPaint(m_hWnd, &ps);
EndPaint(m_hWnd, &ps);
break;

case <span style="color:#ff0000;">WM_CLOSE</span>:
CCDirector::sharedDirector()->end();
break;

case <span style="color:#ff0000;">WM_DESTROY</span>:
destroyGL();
PostQuitMessage(0);
break;

default:
if (m_wndproc)
{

m_wndproc(message, wParam, lParam, &bProcessed);
if (bProcessed) break;
}
return DefWindowProc(m_hWnd, message, wParam, lParam);
}

if (m_wndproc && !bProcessed)
{
m_wndproc(message, wParam, lParam, &bProcessed);
}
return 0;
}

(5.)所以使用基本和VC中鼠标响应事件一样。

第一步.

class Sprite1 : public SpriteTestDemo
{
public:
Sprite1();
virtual std::string title();

void addNewSpriteWithCoords(CCPoint p);
<span style="color:#ff0000;">void ccTouchesEnded(CCSet* touches, CCEvent* event);
</span>};

第二步.【注意】

Sprite1::Sprite1()
{
<span style="color:#ff0000;">setTouchEnabled( true );
</span>

CCSize s = CCDirector::sharedDirector()->getWinSize();
addNewSpriteWithCoords( ccp(s.width/2, s.height/2) );

}

第三步.

void Sprite1::ccTouchesEnded(CCSet* touches, CCEvent* event)
{
CCSetIterator it;
CCTouch* touch;

for( it = touches->begin(); it != touches->end(); it++)
{
touch = (CCTouch*)(*it);

if(!touch)
break;

CCPoint location = touch->getLocation();

addNewSpriteWithCoords( location );
}
}

【注意】：第二步中的setTouchEnabled( true );如果要放在init()里面的话，尽量放到结尾，放在开头不会响应事件。

【吞噬触屏问题解决办法】：/article/2670030.html