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Hey everybody what's going on this is Caleb with Debb slopes dot com.

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And in this video we're going to go ahead and fix our model.

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If you remember a few videos ago I said our model class had a big problem and let's take a look at it

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now.

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So pull open your X code project and we just created an instance of our model.

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Right.

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We set all the properties here.

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But if we go into the model class here we see that these are just simple variables.

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And because of that that means that they are publicly accessible and publicly modifiable.

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So check it out.

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Watch what I can do.

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I can say Apple product name and I could change it to be Samsung s 8.

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Can you see that.

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Now if I build it we're not going to get any problems because that property is totally modifiable.

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Now I'm going to go ahead and build this and show you why this is dangerous.

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Think about this.

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If this model class is loading data from a web site maybe you're downloading data from a Web site.

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If it can be modified or customized by anything other than the class itself it could be dangerous.

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So as you as you saw I modified I modified the name to say Samsung s 8 and check it out.

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I really want the Samsung s 8 in space grey and it cost 999 I should not be able to modify the data

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from my class like that.

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That's very very dangerous.

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So what we're going to do is we're going to change our class here to have what are called private variables

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and a private variable is one that is only accessible within the class that it's involved in.

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So we're going to make these private variables and this will basically lock it down so only our initialiser

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can set the values.

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OK.

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Just like so.

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But watch what happens if I go back to my controller and I try to build this and check it out.

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It says name is X is inaccessible due to private protection level.

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That's good that means we can't access it to change it anymore.

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But it also says it's just plain inaccessible even if we're just trying to get the value.

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So what we need to do is we need to find a way to access the value but only set it inside this class.

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And there's a really elegant way to do this in swift.

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We can make the variable public and it's public by calling public first.

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So it's a public variable with a private sector so we can access it publicly meaning we can access it

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from any other class but we can only set values inside this class.

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That's pretty cool.

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So go ahead and type public again.

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And now what we need to do.

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You can see it saying hey duplicate modifier you can't do that.

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What we need to do is say that we want the setter to be private but the getter to be public so to do

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that all we need to do is put parentheses type set and close parentheses right at the end.

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So a public variable with a private setter very elegant very cool one of the awesome things we can do

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in swift So go ahead and type set again.

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And now if we build you'll notice we're still getting an error.

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Why is that.

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Can not assign to property names center isn't accessible.

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Private sector public Geter so we can get the value but we can not set it.

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Therefore our model is now totally safe.

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And if I build and run my program again you'll see that it will build.

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It'll run successfully and we should see the proper data that we want.

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I really want the iPhone 10 in space grey and it costs nine ninety nine ninety nine.

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Amazing super super cool.

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Our products class here is now totally secure.

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We can access its values publicly but we can only set them within the class when we initialize it.

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Very cool this is a great way to make sure that our code is nice and safe.

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So fantastic work.

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Congratulations on finishing this course.

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I really hope that you've learned a lot.

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And yeah we'll see in the next target topic.

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See you guys.