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Either in this list then you're going to learn how to use dictionaries in swift.

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It's somehow very similar to what you have in Objective C especially from a concept perspective.

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It's exactly the same thing.

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It's just that the syntax is a little bit different.

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So let's go to X code in here and I'm going to start a new playground.

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I'm going to call this Rawn let's call it my dictionaries in the swift.

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So let's see how we got to write our first dictionary.

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So the first thing is I need a variable.

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I'm going to call it dictionary and then dictionary and what I call it to be of the type dictionary

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with values that are extreme and a string.

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This is explicitly telling dictionary what kind of values we're going to have in it.

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And then I could just go ahead and say dictionary are initialized.

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But if you want to be far more explicit which doesn't really make any difference.

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You could say explicitly or type I notated of the type the string and its thing so that's like a much

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longer the most the longest possible way of writing a dictionary.

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What if I wanted to write a lot easier I could just go ahead and say.

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My dictionary is.

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And then within brackets I would say for name key column the value is name and then column or for city

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key column.

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The value is then who were so on and so forth.

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So she value paired items.

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So right these key value pair paired items.

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Not every hair item is so simple as that I can just build my dictionary in either of the vase.

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I can go ahead and change values in them like I would say dictionary value for a something called either

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you.

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IDG unique identification make that this random you know set of characters if they you ID exist is kind

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of updated.

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If it doesn't exist essentially added I could go to my dictionary and say my dictionary value for name

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key make it to be or not.

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I mean and if I go ahead and get access to this value now you will see that when we execute our play

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playground we should see I don't mean here.

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Perfect.

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So that's exactly you know what we expected to see.

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Now the only thing that is left in here is what you play when I go through the items of my dictionary

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how could I go through every item in my dictionary to do that we need to learn a new concept something

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that is completely new in swift and it doesn't exist in Objective-C and that concept we call it a tool.

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So to pros help us do that.

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And before I actually show you how to work let me show you how they work on a dictionary.

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And then from there on we go to using it for other purposes.

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So let me take all of these out and just keep the things that I know I need.

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So that's that.

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And then I don't need a dictionary.

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I don't need that action and I don't want to update my dictionary.

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I only want to have this dictionary.

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So in my dictionary that's called my dictionary.

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I want to do this.

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I want to say four and then I'm going to say J and B.

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In my dictionary do this say trains she is interpretation of Che as the key.

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And then I'm going to copy this pasted on save value is that of course we now let's go ahead and run

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this.

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Well if I was to execute my playground we will see that it says she a name key value is a key is the

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key value is Vancouver.

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And if you have hundreds of items in our dictionary the same thing would happen if we had an array of

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dictionaries.

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It would have been the same thing you would go through the items of the array for each of them we would

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run this thing and would print every value if you wanted to find out if any of these values is equivalent

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to either know a certain name be withdrawn and if statement in the middle of this.

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Now that's all good and well what we don't know is this particular structure.

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How is this working.

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So that is what we call it Tupilak.

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So let's see how a tuple work is essentially a way for containing several values in all their insight

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only one invaluable.

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So I could in theory I could say larrup let's say.

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My name is going to be a Panthers of Amir and Jake for instance.

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So that's essentially a but is it is a tuple of two variables.

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Both of them are or there.

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This is zero.

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This is one and they are sitting inside the variable called my name.

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So if I go in here and say print and in the printer I say my name is zero.

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That's going to print on here I'm guessing.

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Let's see that.

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So yes I was going to print that and then I could of course go ahead and use Avorn or I could do this

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I could go ahead and actually name them I could say first name is here and then last name is J.

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And now I could not only access them by their index I could not live sustained by their names I could

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say print my name by that.

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So let's see how that works.

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And again I get the same thing.

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So tuples are a very good way for combining multiple values that for whatever reason they have to be

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together put them all inside the one variable but give them names.

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Tuples are kind of like.

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They can more concise version of struct.

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So you can kind of think of them as astroid if you already know what they saw.

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So in a programming language if not don't worry about it.

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Once you get to a structure we will learn about those.

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But you put it on much like like a concise and a brief version of a strike that they do things for us

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by giving them names we could potentially you know put this as to be multiple values for different reasons

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so they could be there are user first name last name and then I would say you ID that unique ID is going

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to be somebody else.

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And I would say their email is going to be and thats going to be an email address essentially.

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So on and so forth.

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And now if I wanted to access this guy I could simply go ahead and say user not email.

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I would print for me this particular you know value that it has in its email.

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In this case I mean are the examples that come not this is the same format we are following in a dictionary.

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We are saying give me a tuple of two values let's call them key and.

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Right.

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I'm going to say a tuple that is called Keyon Val inside my dictionary because I know every object in

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here is of that nature is a key and Yvonne.

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And now I could go ahead and say Gee and of course Saval obviously is going to work the way we expect.

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So that's about that.

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That's how we make dictionaries in swift that's how we introduce them as literature.

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If you want we could explicitly tell the compiler that they are dictionaries of the type whatever it

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is they are trying to do.

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You might sometimes in other people's code see it like this that dictionary and then they do something

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like this they write a string on a string.

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And that simply means again they are trying to note that they are trying the they are doing they are

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introducing a dictionary they are declaring a dictionary of the type of string and a string that has

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crunchie no values but it is initialized.

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This is very similar to saying that my array is empty.

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So it is initializing an array.

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There's just nothing.

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It's the same thing here the dictionary here is saying this is the type.

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And there is nothing in it.

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Of course the values could be anything that you want to imagine it could be a string an integer that

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could be a string and any that could be a string and a string depending on your situation and your case

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most likely in a dictionary the keys are a string simply because that's just what makes sense right.

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So with that in mind I think we're good.

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Let's move on to our next lesson.