Cocos2dx实现数字跳动效果

class DigitalBeatText:public cocos2d::Node
{
public:
 DigitalBeatText();
 ~DigitalBeatText();
 static DigitalBeatText *create(int value);
 
 void setValue(int newValue);
protected:
 bool init(int value);
 
 void setValueNoAction(int newValue);
 void startRoll();
 void stopRoll();
 
 void onTimeHandler(float dt);
protected:
 cocos2d::ui::Text * m_txt;
 int  m_lastValue;
 int  m_newValue;
 int  m_valueGap;  //数字跳动间隔
 float    m_scheduleInterval;//调度器间隔
 bool    m_isReverse;  // true: 从大到小
};

DigitalBeatText::DigitalBeatText() 
:m_txt(nullptr)
, m_lastValue(0)
, m_newValue(0)
, m_valueGap(0)
, m_scheduleInterval(1.0f/60.f)
, m_isReverse(false)
{
 
}
 
DigitalBeatText::~DigitalBeatText()
{
}
 
DigitalBeatText* DigitalBeatText::create(int value)
{
 auto pRet = new DigitalBeatText;
 if (pRet->init(value))
 {
  pRet->autorelease();
  return pRet;
 }
 CC_SAFE_DELETE(pRet);
 return nullptr;
}
 
bool DigitalBeatText::init(int value)
{
 if (!Node::init()){
  return false;
 }
 char buff[16] = { 0 };
 m_txt = ui::Text::create();
 m_txt->setFontSize(36);
 sprintf(buff, "%d", value);
 m_txt->setString(buff);
 this->addChild(m_txt);
 return true;
}
 
void DigitalBeatText::setValue(int newValue)
{
 m_isReverse = newValue < m_lastValue;
 stopRoll();
 m_newValue = newValue;
 startRoll();
}
 
void DigitalBeatText::setValueNoAction(int newValue)
{
 m_lastValue = newValue;
 m_newValue = newValue;
 m_txt->setString(cocos2d::StringUtils::toString(m_lastValue));
}
 
void DigitalBeatText::startRoll()
{
 int count = m_newValue - m_lastValue;
 if (count>0){
  m_valueGap = ceil(count / (1.0 / m_scheduleInterval));
 }else{
  m_valueGap = floor(count / (1.0 / m_scheduleInterval));
 }
 schedule(CC_SCHEDULE_SELECTOR(DigitalBeatText::onTimeHandler), m_scheduleInterval);
}
 
void DigitalBeatText::stopRoll()
{
 unschedule(CC_SCHEDULE_SELECTOR(DigitalBeatText::onTimeHandler));
}
 
void DigitalBeatText::onTimeHandler(float dt)
{
 m_lastValue += m_valueGap;
 bool stop = false;
 if (!m_isReverse)
 {
  if (m_lastValue >= m_newValue){
   m_lastValue = m_newValue;
   stop = true;
  }
 }
 else{
  if (m_lastValue <= m_newValue){
   m_lastValue = m_newValue;
   stop = true;
  }
 }
 m_txt->setString(cocos2d::StringUtils::toString(m_lastValue));
 if (stop){
  this->stopRoll();
 }
}

m_index = 1;
m_beatT = DigitalBeatText::create(m_index);
m_beatT->setPosition(visibleSize*0.5);
 this->addChild(m_beatT);
 
m_index += RandomHelper::random_int(0, 100) - 50;
m_beatT->setValue(m_index);