Greenfoot

2019/6/2

#

Im trying to select a random item from an Arraylist and then set the image of an actor to the name of the random item that was chosen. This is my method:

public void setGameScreen()
    {
        while (numCardsHand < 7)
        {
            Card card = new Card();
            card.setImage(cardList.get(cardList.size() + 1) + ".png");
            getWorld().addObject(card, 400, 225);
            
            numCardsHand ++;
        }
    }

I get an error saying cannot find symbol - method size()

danpost

2019/6/2

#

Please show all codes related to cardList in this class.

ChaosPhantom

2019/6/2

#

String[] cardList = {...};

The"..." is just strings I have in the list

danpost

2019/6/3

#

ChaosPhantom wrote...

String[] cardList = {...};

The"..." is just strings I have in the list

Okay -- that is an array (not an arrayList). Use length -- not size().

ChaosPhantom

2019/6/3

#

Thanks, but now its saying the same thing for .get() Is it different for Arrays too?

Super_Hippo

2019/6/3

#

Yes, you don't need to call any methods an arrays. (I think you can't call any methods on arrays at all.) But using the length+1's item in an array won't work because it doesn't exist. Even the length's item doesn't exist. The first item has the index 0 and the last one has the index length-1. (Despite the fact described above, the code would look like this:)

card.setImage(cardList[cardList.length+1] + ".png");

ChaosPhantom

2019/6/3

#

Alright, thank you! Also, its meant to be

Greenfoot.getRandomNumber(cardList.length + 1);

danpost

2019/6/3

#

ChaosPhantom wrote...

Alright, thank you! Also, its meant to be

Greenfoot.getRandomNumber(cardList.length + 1);

Remove the '+1'. The last element is indexed one less than the length of the array (since counting starts at zero).

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