WEBVTT

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The third step is to create the retrofit provider, select new object, name it as Retrofit Provider.

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Inside this object, we need to create a function that provides us with the directions service instance

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function create direction service that returns a directions service instance.

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This function takes a base URL as a string parameter.

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Don't worry, we're going to clarify everything in this example.

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Now return retrofit builder dot base url alt+.

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Enter to import retrofit instance base url.

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Pass the base URL parameter passed by the create directions service and add converter.

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Factory JSON for converter factory dot create dot build function dot create direction service class.

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This is what we've done and we talked about in the previous sections and in previous applications when

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we worked with retrofit.

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But don't worry, we're going to make a quick recap about it.

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This object defines a utility object called retrofit Builder, and the retrofit provider that creates

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and provides instances of retrofit service for directions related API calls.

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The object declaration object retrofit provider.

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This creates a singleton object.

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Only one instance exists in the application.

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No need to instantiate it.

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You can call its functions directly via retrofit provider dot create directions service, for example,

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or any function name.

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Create directions service is a function taking a base URL string as a parameter.

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Returning an implementation of directions service.

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The retrofit builder starts building a retrofit instance.

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Base URL sets the base URL for all API calls.

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As I said to you, the base URL of the URL of the API is the constant part of the API call dot add converter

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factory adds.

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As the converter for JSON serialization and deserialization as we talked about.

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Retrofit.

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It needs a converter that uses.

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That uses serialization and deserialization for converting JSON and JSON response to Kotlin objects

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and vice versa.

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Build finalizes and creates the retrofit instance.

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Create a function.

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Generates an implementation of direction service interface.

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This is a clean way to centralize retrofit service creation.

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The directions service is an interface defining API endpoints.

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Decent is used for JSON conversion.

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You could swap this for emoji or other converters, but as I said to you, JSON is the more professional

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and it's fast.

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The base URL is parameterized for flexibility.

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Could point to different environments.

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Okay, so this pattern is commonly used in Android application to abstract away retrofit setup and provide

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easy access to API services.