Fragment class to communicate with another class ArrayList


Hey I am guys I am making a next button inside my Fragment class to go through an ArrayList all the way around and back to the 0 index without crashing,
problem is that I don’t have the arraylist in my fragment class but it is in my other set class, how can I make them communitcate so I everytime I press the
next button my program won’t crash and goes back to 0 and then back around, any helpful advice? and also my previous button thanks!!!