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All right.
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So in this lesson, I'm going to talk about Third Party Libraries, what they are, and how to use them using
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something called CocoaPods.
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What exactly are third party libraries anyways?
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Well, let's imagine that you have an assignment where you have to write an essay about volcanoes. And, yeah,
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you know a little bit about volcanoes already, you know that they're kind of pointy, and they're kind of hot,
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and sometimes they emit a lot of gas, which could probably be said of my roommate, too, but you
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might not know that, for example, volcanoes are named after the Roman god Vulcan, which is this blacksmith
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dude, who's really good with fire, or the fact that maybe the largest volcano is actually on Mars and
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it's something like 370 miles across which is like about six hundred kilometers in
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diameter.
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So where would you find these kind of things out?
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Well, you might have gone to an actual library, right, and you could take out a book on volcanoes.
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So between this book and your knowledge, you can actually cobble together this essay.
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Now, I'm not saying this is how you should write essays, copy things from books or from Wikipedia.
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But, essentially, a lot of times, you don't have the knowledge or the capabilities or the time to be able to
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completely create something by yourself.
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So in the case of the app, you can actually combine your code with third party library code that other
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people have created, and you're able to leverage these third party libraries of code which contain individual
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modules for specific purposes,
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say, for example, an animation library that helps you animate the components of your app, or a Lintel library
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which helps you fix and improve your Swift code, or something like Firebase which we're going to be using
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a little bit later on in order to work with the databases on Firebase and in Cloud storage.
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So, essentially, you end up standing on the shoulders of giants saving yourself lots of time and, also,
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occasionally being able to do things you might not have otherwise known how to do.
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So let's go ahead and see this in action.
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Now, the first thing I want you to do is to actually close down the project that you're currently working
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with. And in your browser, head over to cocoapods.org.
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This is the tool that we're going to be using to search for and incorporate some third party libraries
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into our project.
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Now, when you go to cocoapods.org, there is a search bar which, admittedly, sometimes it doesn't work
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that well, but most of the time, as long as the server's up and running, you should be able to type stuff
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in here.
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Say, for example, if I wanted to find a library that helps me create a typing animation, then I could search
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for the word "typing,"
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and you can see a whole bunch of different libraries that we can add.
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So this top one which is a UILabel with character by character typing animation written in Swift,
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so that sounds pretty good,
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that sounds pretty much like exactly what we want,
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right?
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So if you go ahead and click on it, one of the key things you have to do is judge whether if these libraries
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are well maintained and if they're updated regularly.
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So you can see some of this information over here.
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You can see that the builds are passing.
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So these are automatic builds and tests that are run on this library of code. And you can also see when
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it was last updated.
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So you can see this one was last updated in October 2019.
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And right now, it's October 2019 as I'm recording this,
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so that's pretty good.
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Now, the other thing that you can see is when you go ahead and click on this link here with the little
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GitHub Octocat. It takes you to where that code is hosted.
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So, it's usually going to be on GitHub.
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And here you can actually look through the code that enables this capability.
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For example, if we go into Pod and then we go into Classes, we can see that this is pretty much the
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class that's enabling the functionality.
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So it basically subclasses our UILabel and adds a whole bunch of capabilities to it in order for it
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to animate
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with that typing animation.
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So when you're on GitHub, a quality indicator or at least a popularity indicator is by looking at the
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number of people who have started this project or repository.
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So this one has 65.
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And if you were to go back and compare some of the competing ones which also have this functionality
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and look at how many stars they have, then you'll be able to roughly judge how many people actually have
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used this, and how many people are interested in it as a sort of proxy for quality.
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So, now that we found this pod that we'd like to enable in our project to get something like this going
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on, how do we actually do it?
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Well, usually on the read-me page,
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so on the main page of the project that you get linked to from CocoaPods, you'll get a section on installation.
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And you can see that there's usually a whole bunch of different options.
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You can either do it manually by copy and pasting this file into your Xcode project. And I don't recommend
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doing it like this because there's usually a lot of updates that happen to Swift and to Xcode, and that
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means that you're going to be responsible for maintaining the code afterwards if you want to add it
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manually.
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Alternatively, you would have to monitor for changes in this repository and see when the author updates
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their code, and then copy and pasting it again whenever that happens.
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That's really, really tedious.
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So instead, we're gonna be using this great tool called CocoaPods. In the next lesson,
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I'm gonna show you how to install CocoaPods onto your Mac.