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Welcome back in this video, we're going to look at what retrofit is in order to then being able to

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use it because we're going to use it in order to get data out from the internet, which we then want

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to display because the news is something that is constantly being updated, right?

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And that's not something we would have locally on our PC.

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So on our phone, we need to get it from the internet.

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So let's look at what a retrofit is.

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Therefore, we first need to understand what a restful API is.

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So API stands for application programming interface, which is a set of rules that defines how applications

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can communicate with each other.

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And then there are rest APIs.

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So representational state transfer API ice, which are restful APIs, and it is a web application programming

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interface that provides a flexible way of communicating and integrating applications with online backend

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or servers.

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So networking in Android is mostly associated with connecting your Android application to a backend

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server to ensure a user's proper data management and synchronization between all of their devices.

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Applications need to connect to an online bank, and so users can have proper back up on their personal

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data and easily switch devices without fear of loss of data.

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So let's look at the networking process for network to be successful.

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There needs to be a client and a server so a client can be any of your devices, phones or tablets,

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laptops or even browser.

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While the server can be any central computer or program that controls or provides the information that

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you need and the client.

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So your phone, for example, sends a request to the server and the server then sends a response back

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with retrofit.

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Connecting your Android application to an online server becomes a lot easier.

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You can use its abstracted interfaces to request data and receive responses from the server.

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It's a third party library because it was not created by Google, but by an external team of developers.

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So let's look at retrofits most used methods that can be used to make specific requests to a rest API.

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And the first one will be at Get.

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So the Get method tells the server that you need to read data from it.

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Then there is the post method that tells the server you need to create or add data to it.

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Then there's the method that tells the server that you need to update an already existing piece of data.

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And finally, we have the delete method that tells the server that you need to delete specific data

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from it.

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So it's actually a create, read, update and delete process, which is also known as chroot operations.

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So Create C are for it you for update and D for delete.

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So crude operations will learn more about using Retrofit with Android throughout the section.

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So we're going to actually use Retrofit and we'll get our data from the internet in order to display

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it in our application.