CCControlPotentiometer是电位计按钮，和CCControlSlider的用法很相似。关于控件使用时的一些配置，请参见文章：UI开发之控件类-CCControlButton。
bool HelloWorld::init()
{
bool bRet = false;
do
{
CC_BREAK_IF(!CCLayer::init());
//CCControlPotentiometer参数是底座，进度条，控制按钮图片资源
CCControlPotentiometer * potentiometer = CCControlPotentiometer::create("potentiometerTrack.png",
"potentiometerProgress.png","potentiometerButton.png");
//设置最大值和最小值以及初值
potentiometer->setMaximumValue(100.0);
potentiometer->setMinimumValue(0.0);
potentiometer->setValue(50);
potentiometer->setPosition(ccp(240,160));
this->addChild(potentiometer);
//添加事件监听
potentiometer->addTargetWithActionForControlEvents(this,cccontrol_selector(HelloWorld::valueChanged),
CCControlEventValueChanged);
bRet = true;
}
while(0);
return bRet;
}
void HelloWorld::valueChanged(CCObject * pSender,CCControlEvent controlEvent)
{
CCControlPotentiometer * potentiometer = (CCControlPotentiometer *)pSender;
CCString * string = CCString::createWithFormat("%f",potentiometer->getValue());
CCLog(string->getCString());
}
