TheDancerCodes / retrofit-livedata-call-adapter

This is a simple Retrofit Adapter for Android LiveData that you can easily integrate in your applications.

Retrofit LiveData Call Adapter

This is a simple Retrofit Adapter for Android LiveData that you can easily integrate in your applications.

Original Credit: I leverage the classes from one of the Android Architecture Google Samples. This is Google's recommended way of architecting your apps if you choose to leverage Architecture Components, especially LiveData.

Set Up

To use the library you need to do the following steps:

[1] Add the following gradle dependency in your app/build.gradle file

dependencies {
  implementation 'com.thedancercodes:livedatalibrary:1.0.1'
}

[2] Ensure that your Retrofit dependency is accessible from your project level build.gradle file. This is because the library leverages this dependency. Declare it as follows:

ext {
    retrofit = '2.6.0' // This is the version of Retrofit you are using in your project.
}

Permissions

Don't forget to add the following permission:

<uses-permission android:name="android.permission.INTERNET"/>

Usage

Set the LiveDataCallAdapterFactory in the Retrofit Builder

Retrofit.Builder()
        .baseUrl(BASE_URL)
        // ....
        .addCallAdapterFactory(LiveDataCallAdapterFactory())
        // ....
        .build()

Update the your ApiService from the Original Way to the New Way as shown below:

Original Way - with Call:

interface PostService {

    @GET("posts")
    fun getPosts(): Call<Post>
}

New Way - with LiveData:

interface PostService {

    @GET("posts")
    fun getPosts(): LiveData<ApiResponse<Post>>
}

---

NOTE: Your service methods can now use LiveData as their return type. 👆🏾

Also, note the usage of the ApiResponse object. It is a common class used by API responses when you want verify what is happening on your network call, so that you can ideally respond to the Api Response.

See the example implementation below: 👇🏾

    postViewModel.finalPosts.observe(this, Observer { response ->

        when(response) {
            is ApiResponse.ApiSuccessResponse -> {
                // Set new data into your adapter
                adapter.setPosts(response.body)
            }

            is ApiResponse.ApiErrorResponse -> {
              // Display the Error message in a Snack Bar.
              val snack = Snackbar
                  .make(recyclerview, response.errorMessage, Snackbar.LENGTH_LONG)
              snack.show()
            }

            is ApiResponse.ApiEmptyResponse -> {
              // Display the message for an Empty Response in a Snack Bar.
              val snack = Snackbar
                  .make(recyclerview, "Empty Response", Snackbar.LENGTH_LONG)
              snack.show()
            }
        }
    })

NOTE: Checkout the sample-app for an in-depth example of this implementation.

License

MIT License

Copyright (c) 2020 Roger Taracha

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.