public void notifyListeners() {
    if (L.isTraceEnabled()) {
      L.beginSection("BaseKeyframeAnimation#notifyListeners");
    }
    for (int i = 0; i < listeners.size(); i++) {
      listeners.get(i).onValueChanged();
    }
    if (L.isTraceEnabled()) {
      L.endSection("BaseKeyframeAnimation#notifyListeners");
    }
  }
@param <K> Keyframe type
@param <A> Animation type
lottie/src/main/java/com/airbnb/lottie/animation/keyframe/BaseKeyframeAnimation.java