public void activate(final Nifty nifty, final Element element, final EffectProperties parameter) {
// startColor and endColor (only alpha component used) are the old version of this
// and are kept here only for backward compatibility. The current attributes are "start" and "end" alpha values.
if (parameter.getProperty("startColor") != null) {
start = new Alpha(new Color(parameter.getProperty("startColor", "#000000ff")).getAlpha());
}
if (parameter.getProperty("endColor") != null) {
end = new Alpha(new Color(parameter.getProperty("endColor", "#ffffffff")).getAlpha());
}
if (parameter.getProperty("start") != null) {
start = new Alpha(parameter.getProperty("start"));
}
if (parameter.getProperty("end") != null) {
end = new Alpha(parameter.getProperty("end"));
}
interpolator = parameter.getInterpolator();
}