Why does Collections.shuffle();not work?

KiraCZE

Hello guys, I'm wondering why my shuffle method doesn't work. Im trying to shuffle my arraylist Arraylist <Card> cards = new Arraylist <Card>(8); where I draw the images like

for (int y = 0; y < 3; y++){
    for (int x = 0; x < 4; x++){
        fv++;
        if (fv==6){
            fv=0;
        }
        cards.add( new Card (x*105+20, y*150+20, 105, 150, fv));
    }
}
Collections.shuffle(cards); 

I've imported the java.util.Collections but the images are always on the same place. Can you help me ? Thanks

(If you are wonderig what's the fv it's a face value)

GoToLoop

It's pretty hard to study your code messed up like that. Please format it properly:
https://forum.Processing.org/two/discussion/8045/how-to-format-code-and-text

In a quick glance, I can't see anything wrong. Collections.shuffle() should simply work:
http://docs.Oracle.com/javase/8/docs/api/java/util/Collections.html#shuffle-java.util.List-

quark

All you are doing is changing the order the cards are drawn because each cards position is fixed when it is created.

KiraCZE

Oh now I get it I think. Do you think making a second arraylist where I put the images from the first would help? And if yes could you help me ? Thanks btw for the answer

GoToLoop

I've got this example of a card deck. Maybe it can help ya: :)

https://forum.Processing.org/two/discussion/2801/picking-cards-at-random-then-excluding-those-from-further-picking

quark

Do you think making a second arraylist where I put the images from the first would help?

Yes create an arraylist of images ArrayList <PImage> cardpics then shuffle them with Collections.shuffle (cardpics); then in draw you can display them with something like

int cn = 0;
For (int y = 0; y < 3; y++){
    for (int x = 0; x < 4; x++){
        image (cardpics.get (cn++), x*105+20,  y*150+20);
    }
}