**Heads up!** To view this whole video, sign in with your Courses account or enroll in your free 7-day trial.
Sign In
Enroll

Start a free Courses trial

to watch this video

In this video we'll create an object to represent one of the foundation piles!

Our model now has a deck and a waste pile. 0:00 But it still needs foundation piles and tableau piles. 0:03 Let's keep on modeling by creating a class to help represent a foundation pile. 0:06 Just like with the waste pile, we should start by analyzing 0:11 what requirements we have for a foundation pile. 0:14 The first requirement is that each foundation pile 0:17 needs to correspond to a specific suit. 0:20 They also require that their cards follow a nice orderly progression 0:23 from As to king, zero to 12. 0:27 Along with those requirements, 0:29 we also need to be aware of which actions can happen to a foundation file. 0:31 Just like with our waste file, 0:36 there's only three things that can happen to a foundation file. 0:38 We can add a card, we can remove a card, and we can reset to an empty pile. 0:41 Now that we know what it takes to make a foundation pile, 0:47 let's make a foundation pile. 0:50 Start by creating a new class named FoundationPile. 0:52 Then, since each foundation pile needs to correspond to a specific suit, 1:01 let's add a constructor. 1:05 And inside, let's add a suit parameter, which will be a String. 1:08 And then, let's upgrade our suit parameter into an immutable property 1:13 by adding the val keyword. 1:17 Next, let's create a property to represent the cards 1:20 contained in this foundation pile. 1:23 Val cards, which is going to be a MutableList of Cards. 1:26 And let's set it equal to an empty list. 1:34 Now, all that's left are the actions. 1:37 We need to be able to add a card, remove a card and reset our pile to empty. 1:40 Let's start with resetting our pile. 1:45 Let's create a new function named reset, and then inside this function, 1:47 let's type cards.clear to remove all the items from our cards list. 1:52 Next, let's handle removing a card. 1:59 Let's create a new function name to removeCard which takes in a card, 2:02 And then removes that card from the cards list. 2:10 So cards.remove and then pass in the card we'd like to remove. 2:13 Finally let's finish up our foundation class by adding our add card function. 2:20 This function will take in a card and if it's a match it will add it to the cards 2:25 property and return true to tell our model that we found a match. 2:30 If it's not a match, it will return false and our model will be sad. 2:35 Let's declare this function by typing fun, addCard. 2:39 Adding a card object for the parameter and returning a Boolean. 2:44 Nice. 2:53 Now we just need to figure out if the card parameter is a match for 2:54 the next card in our foundation. 2:58 If our foundation is empty, the next card would be the ace. 3:00 Which corresponds to a value of zero. 3:04 Inside the addCard function, let's declare a mutable property named, nextValue. 3:06 And let's set it equal to 0, which is the value of the ace. 3:15 Then on the next line, let's add an if statement to check if there are already 3:19 any cards in our foundation. 3:24 If cards.size > 0. 3:25 And if there are, let's update our next value property to be 3:33 equal to the value of the last card in our foundation plus one. 3:37 So nextValue = cards.last.value + 1. 3:41 Cool. 3:52 Next, we need to check if the suit of our card parameter 3:53 matches the foundation suit. 3:56 We also need to check that the value of our card parameter 3:58 matches with our next value property. 4:02 Let's add a line below the if statement and 4:04 then type if card.suit is equal to 4:07 our super parameter or suit property and 4:12 the cards value Is equal to our nextValue property. 4:19 And if that's true then we've got a match, and 4:26 we want to add this card to our card's property. 4:29 Cards.add and pass in our card. 4:32 And then return true to let our model know that we found a match. 4:36 Finally, let's add return false at the end to finish off our addCard function. 4:41 Which also finishes our foundation class. 4:48 Awesome. 4:50 Now let's head back to our GameModel and create a property for 4:51 our foundation piles. 4:55 Let's add a line below our waste pile, and type val foundationPiles, 4:57 which will be an Array of FoundationPiles. 5:05 And let's set it equal to arrayOf. 5:12 And for the parameters, let's pass in one foundation pile for each suit. 5:15 So FoundationPile of Clubs. 5:19 Then a FoundationPile of Diamonds. 5:24 And I'm going to put these on a new line, so it's easier to see. 5:29 And a FoundationPile of Hearts and then a FoundationPile of Spades. 5:35 And remember since this is clearly going to give us an array 5:46 of foundation piles we can get rid of the data type. 5:49 Nice. 5:54 Now that we're finished with our foundation pile object. 5:55 We need to create an object to represent a tableau pile. 5:58 But before we get the tableau piles, 6:01 let's see if we can't find a way to stop repeating ourselves with these card suits. 6:03

You need to sign up for Treehouse in order to download course files.

Sign up