Retrofit, a simple REST client for Android

Transcript

1. Retrofit, a simple REST client for Android Wilfredo Nieves Software Development Director @Optivon, Inc.
2. @WillNieves19
3. Optivon, Inc.
4. Retrofit
5. Used it?
6. What is Retrofit?
7. What is Retrofiit? • Type-safe REST client for Android • Model your remote API’s as interfaces. • Developed by Square • Made open source in 2010 (Retrofit 1) • Leverages Java annotations describe HTTP requests.
8. What does it do? • Consumes remote API’s • HTTP requests (POST, GET, PUT, DELETE, etc.) • File uploads • Authentication • Serializes JSON or XML responses to POJO’s (Plain Old Java Objects)
9. What we used before Retrofit? • Java Thread • Handlers • AsyncTask • Volley
10. Performance
11. Why use Retrofit • Easy to use • Wraps up Thread communication • Exception management. • Plenty of code examples on the web • Strong community
12. What do we need? • POJO (Plain Old Java Object) • API service declarations (Java interfaces) • RestAdapter • android.permission.INTERNET Permission
13. Plain Old Java Objects • Java Model class • Fields define a response from the API • Use the @SerializedName annotation to map response field name.
14. Service Endpoints • Create a Java interface to describe your API endpoints • Use annotations to specify request type and headers • Callback parameter for asynchronous calls
15. Other Annotations Examples
16. Other Annotations Examples
17. Other Annotations Examples
18. Rest Adapter • Retrofit class adapts a Java interface to HTTP calls by using annotations • Build using the base URL of the API and a Converter object • Use the create method to generate an implementation
19. Asynchronous Request • The Call class sends a request to a webserver and returns a response • Use the enqueue() method to make an asynchronous requests, execute() for synchronous. • To cancel a request just: call.cancel() • Clone instances with: call.clone()
20. Response • Parameterized Response object • Response info. • Code • Success • Message • Headers • Raw body • Error body
21. New in retrofit 2.0 • OkHttp is the default connection interface (is automatically added) • Pluggable JSON and XML converters, even create them yourself • Gson: com.squareup.retrofit:converter-gson Jackson: com.squareup.retrofit:converter-jackson Moshi: com.squareup.retrofit:converter-moshi Protobuf: com.squareup.retrofit:converter-protobuf Wire: com.squareup.retrofit:converter-wire Simple XML: com.squareup.retrofit:converter-simplexml
22. Let’s write some code
23. github.com/wnieves19/
24. References • http://square.github.io/retrofit/ • https://futurestud.io/tutorials/retrofit-getting-started-and-android- client • https://instructure.github.io/blog/2013/12/09/volley-vs-retrofit/ • https://inthecheesefactory.com/blog/retrofit-2.0/en
25. Thanks!