previous method
void
previous()
Implementation
void previous() {
cancelHider();
if (animationController.value < 0.25) {
currentIndex = currentIndex! - 1;
_callFunctions(_onIndexChangeds);
}
if (currentIndex! <= 0) {
currentIndex = 0;
}
animationController.reset();
animationController.duration = currentStory.duration;
play();
}