Retrofit

• Retrofit is a REST client for Android, Java and Kotlin developed by Square.
• The library provides a powerful framework for authenticating and interacting with APIs and sending network requests.
• This library makes downloading JSON or XML data from a web API fairly straightforward. Once the data is downloaded then it is parsed into a Plain Old Java Object (POJO) which must be defined for each "resource" in the response.

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How to use :-

• Retrofit turns your HTTP API into a Java interface.

  public interface MLModelService {
  @POST("uploadfile")
  @Multipart
  Call<MLResponse> upload(@Part MultipartBody.Part filePart);
  }

• The Retrofit class generates an implementation of the GitHubService interface.

  Retrofit retrofit = new Retrofit.Builder()
      .baseUrl(https://qurany.herokuapp.com/")
      .build();
  MLModelService service = retrofit.create(MLModelService.class);

• make a call and get Response

   repository.uploadFile(file).enqueue(new Callback<MLResponse>() {
          @Override
          public void onResponse(Call<MLResponse> call, Response<MLResponse> response) {
            
          }
  
          @Override
          public void onFailure(Call<MLResponse> call, Throwable t) {
          }
      });

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Our App

1. create interface, service, build retrofit.

   • use Multipart to upload auido file as encoded in POST request.

2. prepare audio file.

   • make file object File file = new File(path); // path of audio file.
   • create RequestBody to be sent with POST

       RequestBody requestBody = RequestBody.create(MEDIA_TYPE_AUDIO, file);
       requestBody = new MultipartBody.Builder()
               .setType(MultipartBody.FORM)
               .addFormDataPart("file", "filename.mp4",
                       RequestBody.create(MEDIA_TYPE_AUDIO, fileObj)
               .build();
      

3. upload audio to api using Retrofit.

    repository.uploadFile(file).enqueue(new Callback<MLResponse>() {
           @Override
           public void onResponse(Call<MLResponse> call, Response<MLResponse> response) {
                   // get response as text of Recognized Text.
           }
   
           @Override
           public void onFailure(Call<MLResponse> call, Throwable t) {
           }
       });

4. process response and diplay results to user.