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Everybody what's going on says Caleb with deps Lopes dot com.

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And in this video.

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Get excited.

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We're going to create our model layer.

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All right.

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This app that we're going to build is basically going to just display some information about a particular

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apple product that we want to buy.

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So in order to actually set this up we're going to go ahead and create a class that will act as our

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model layer to create instances of our Apple product so pull open your project we're going to right

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click on the model folder in X code.

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We're going to click new file like so.

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And we don't need to do anything other than a basic swift file for a model class case so go ahead and

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we're going to name this Apple product and go ahead and click Create your class we'll pull up here.

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And the cool thing is we shouldn't actually need to use anything other than Foundation.

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The most core fundamental swithe types and that is true or I guess we could also use custom types but

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that doesn't require foundation.

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So anyway let's move on and create our class.

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Now you should know about classes you should have a good fundamental understanding of the swift programming

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language before diving into this course.

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So let's create a class called Apple product.

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OK so remember this is our model layer so we need to think what is the blueprint what are we going to

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help them build we can think of our model class as an instruction set to build an Apple product so we

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can create both properties and functions K properties being variables or constants are things about

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our class that make it that way.

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So an Apple product for instance has a name iPhone 10 an Apple product has a color space gray or silver

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an Apple product has a price 399 499 999 $15 billion.

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It has a price but there are other things that make Apple products Apple products right.

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They can do stuff they can make calls they can send messages they can connect to the Internet.

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They can do all kinds of amazing things.

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So that's where functions would come in in a class.

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But for now we're just going to go ahead and create some properties that make an Apple product an Apple

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product.

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And so we're going to go ahead and begin by creating the variable var name and a name is a text data.

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So we should use the type String var name is going to be of type string.

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OK.

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And it's going to tell me class Apple product has no initializers.

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That's because we have not yet created an initialiser function but we will next.

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So OK our Apple product has a name.

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Next we need.

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How about a color var color.

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And you know what we could use all kinds of different things.

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But let's just go ahead and use a string and pass in the word for whatever color our Apple device will

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be next.

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How about a price.

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Var price.

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And we're going to go ahead and use the number type double which includes a floating point decimal value

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because you know the price is going to come in with a certain number of dollars and cents.

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So there's that.

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We have a name we have color we have price.

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And let's just leave it at that for now.

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So now it says we have no initializers.

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We need to create a function that is going to essentially run through and set all the values for this

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particular model layer and create an instance of it in memory that we can use.

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So to do that go ahead and just call init and pass in three parameters.

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We have one name of type String.

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We have a second one color also of type string.

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And apparently I can't type.

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And we have.

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Price of type double.

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Now in order to set these properties all we need to do is to type self-caused name referring to this

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property here.

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We're going to set it to be equal to the name property passed in from the function and to do that we

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just need to call name.

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Then below that we're going to call self-caused color and set it to be color the 10:01 from the function

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beneath that type self price.

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And we're going to pass in price just like that.

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So we have now successfully created the class but there's a problem a very big problem and I'm going

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to show you what that is in a future video.

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This is not a very safe class.

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We're going to show you a better way to make it safer in a future video.

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But for now this will work.

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We have a class called Apple product.

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It has three properties.

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Name color and price and it also can be initialized.

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We can create an instance of it and then use it in our application.

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So cool so to show you how this works I'm actually going to create a constant called Apple product and

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I'm going to set it to be equal to Apple product and watch this if I go ahead and put an open parentheses.

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It's going to ask me to autocomplete and if I do you'll see I can pass in three properties.

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This is our initialiser function being called.

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So for my name I might say iPhone 10 for the color I might say space gray.

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And for the price I might say nine hundred ninety nine point ninety nine for the retail price of the

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iPhone 10.

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Now the cool thing what I can do here is I can access these properties.

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So now that I've created an instance of Apple product here and this constant I could print out Apple

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product Dot and I could choose any of those properties Apple product name and I could print that to

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the console.

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I could print out Apple product color.

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I could print out a Apple product up price if I were to cast it as a string but it's not because it's

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double.

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But anyway this is it guys we can now create an instance of our class.

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But like I said there are some issues here.

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These variables have an issue and we're going to fix it in a future video.

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But guys amazing work.

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We now have our model layer Apple product and we can use that to create an instance of our data model.

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Very very cool stuff guys.

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In the next video we're going to dive into the world of view and we're going to create a custom view

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that we can actually display on the screen and I'll show you how it works I'll show you how we can interface

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with the View Controller and help the View Controller to present that view.

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So let's head over there now and I'll see you there.