Android, randomize arrayList.add(Object)

Question

How to randomize ArrayList.add(Object)?

Random random = new Random();

ArrayList arrayList = new ArrayList();
arrayList.add((Object)("one"));
arrayList.add((Object)("two"));
arrayList.add((Object)("three"));
arrayList.add((Object)("four"));
arrayList.add((Object)("five"));

How can i randomize above code? not sure how else could i explain? — Mihir, Apr 02 '14 at 19:09
@njzk2, I believe Mihir wants to insert new items at a random position in the ArrayList. — Bryan Herbst, Apr 02 '14 at 19:10
[Randomise after adding the values](http://stackoverflow.com/questions/4228975/how-to-randomize-arraylist) — PrR3, Apr 02 '14 at 19:12
Thanks PrR3 - i was looking for "Collections.shuffle(arrayList); — Mihir, Apr 02 '14 at 19:16
Guys i'm getting -5 points for this question, how else one could ask this question? — Mihir, Apr 02 '14 at 19:19
Most of the downvotes are likely because this question is easily solvable with a little bit of research, and a good StackOverflow question demonstrates shows that you have made an attempt to research your question before asking. — Bryan Herbst, Apr 02 '14 at 19:25
i did know how to randomize regular array, but didn't know how to randomize above array. Oh well, next time will be more careful :) thanks — Mihir, Apr 02 '14 at 19:28
downvotes come from this question being solvable by googling `random arraylist` and a few seconds — njzk2, Apr 02 '14 at 20:26

score 1 · Answer 1 · answered Apr 02 '14 at 19:19

The easiest method of accomplishing this is to call Collections.shuffle(List, Random) on your ArrayList after you have inserted all of the elements.

If you really want to do this as you insert the items instead, you can use add(int, E) to specify the position at which you need to insert the item. Something like this would do:

arrayList.add(random.nextInt(arrayList.size()), "MyString");

Android, randomize arrayList.add(Object)

1 Answers1