const char* const SIGNAL_ON_STAGE = "on-stage";
const char* const SIGNAL_OFF_STAGE = "off-stage";
const char* const ANIMATION_SIGNAL_FINISHED = "finished";
const char* const SIGNAL_ON_STAGE = "on-stage";
const char* const SIGNAL_OFF_STAGE = "off-stage";
const char* const ANIMATION_SIGNAL_FINISHED = "finished";