touchgfx::FadeAnimator

class FadeAnimator : public T { public:     FadeAnimator() :         T(),         fadeAnimationRunning(false),         fadeAnimationCounter(0),         fadeAnimationDelay(0),         fadeAnimationEndedCallback(0)     {     }     virtual ~FadeAnimator()     {     }     void setFadeAnimationEndedAction(GenericCallback<const FadeAnimator<T>& >& callback)     {         fadeAnimationEndedCallback = &callback;     }     void clearFadeAnimationEndedAction()     {         fadeAnimationEndedCallback = 0;     }     virtual void setFadeAnimationDelay(uint16_t delay)     {         fadeAnimationDelay = delay;     }     virtual uint16_t getFadeAnimationDelay() const     {         return fadeAnimationDelay;     }     virtual bool isRunning() const     {         return isFadeAnimationRunning();     }     virtual bool isFadeAnimationRunning() const     {         return fadeAnimationRunning;     }     void startFadeAnimation(uint8_t endAlpha, uint16_t duration, EasingEquation alphaProgressionEquation = &EasingEquations::linearEaseNone)     {         if (!fadeAnimationRunning)         {             Application::getInstance()->registerTimerWidget(this);         }         fadeAnimationCounter = 0;         fadeAnimationStartAlpha = T::getAlpha();         fadeAnimationEndAlpha = endAlpha;         fadeAnimationDuration = duration;         fadeAnimationAlphaEquation = alphaProgressionEquation;         fadeAnimationRunning = true;         if (fadeAnimationDelay == 0 && fadeAnimationDuration == 0)         {             nextFadeAnimationStep();          }     }     void cancelFadeAnimation()     {         if (fadeAnimationRunning)         {             Application::getInstance()->unregisterTimerWidget(this);             fadeAnimationRunning = false;         }     } protected:     virtual void handleTickEvent()     {         T::handleTickEvent();         nextFadeAnimationStep();     }     void nextFadeAnimationStep()     {         if (fadeAnimationRunning)         {             if (fadeAnimationCounter < fadeAnimationDelay)             {                 fadeAnimationCounter++;             }             else             {                 if (fadeAnimationCounter <= (uint32_t)(fadeAnimationDelay + fadeAnimationDuration))                 {                     uint32_t actualAnimationCounter = fadeAnimationCounter - fadeAnimationDelay;                     int16_t deltaAlpha = (int16_t)fadeAnimationAlphaEquation(actualAnimationCounter, 0, fadeAnimationEndAlpha - fadeAnimationStartAlpha, fadeAnimationDuration);                     T::setAlpha(fadeAnimationStartAlpha + deltaAlpha);                     T::invalidate();                     fadeAnimationCounter++;                 }                 if (fadeAnimationCounter > (uint32_t)(fadeAnimationDelay + fadeAnimationDuration))                 {                     fadeAnimationRunning = false;                     fadeAnimationDuration = 0;                     Application::getInstance()->unregisterTimerWidget(this);                     if (fadeAnimationEndedCallback && fadeAnimationEndedCallback->isValid())                     {                         fadeAnimationEndedCallback->execute(*this);                     }                 }             }         }     } protected:     bool           fadeAnimationRunning;            uint16_t       fadeAnimationCounter;            uint16_t       fadeAnimationDelay;              uint16_t       fadeAnimationDuration;           int16_t        fadeAnimationStartAlpha;         int16_t        fadeAnimationEndAlpha;           EasingEquation fadeAnimationAlphaEquation;      GenericCallback<const FadeAnimator<T>& >* fadeAnimationEndedCallback;  };