Retrofit2 使用经验

基本使用方法

1 准备工作

build.gradle:

dependencies {      // Retrofit & OkHttp    compile 'com.squareup.retrofit2:retrofit:2.0.0'    compile 'com.squareup.retrofit2:converter-gson:2.0.0' }说明：Retrofit2.0默认使用okhttp进行网络处理，不用单独添加。除非你需要特定的版本

2 定义ServiceGenerator：

public class ServiceGenerator {    public static final String API_BASE_URL = "http://your.api-base.url";    private static OkHttpClient.Builder httpClient = new OkHttpClient.Builder();    private static Retrofit.Builder builder =            new Retrofit.Builder()                    .baseUrl(API_BASE_URL)                    .addConverterFactory(GsonConverterFactory.create());    public static <S> S createService(Class<S> serviceClass) {        Retrofit retrofit = builder.client(httpClient.build()).build();        return retrofit.create(serviceClass);    }    }

3 定义请求接口：

GET：

public interface GitHubClient {      @GET("/repos/{owner}/{repo}/contributors")    Call<List<Contributor>> contributors(        @Path("owner") String owner,        @Path("repo") String repo    );}public class Contributor {      String login;    int contributions;}

4 发起网络请求

public static void main(String... args) {      // Create a very simple REST adapter which points the GitHub API endpoint.    GitHubClient client = ServiceGenerator.createService(GitHubClient.class);    // Fetch and print a list of the contributors to this library.    Call<List<Contributor>> call =        client.contributors("fs_opensource", "android-boilerplate");    try {        List<Contributor> contributors = call.execute().body();    } catch (IOException e) {        // handle errors    }    for (Contributor contributor : contributors) {        System.out.println(                contributor.login + " (" + contributor.contributions + ")");    }}

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进阶《一》

GET方法：

@Path:路径参数@Query:?后面的参数，例如：?expand="dddddd"@GET("users/{user_id}/activities/{name}/reward")    Call<ResponseBody> putReward(            @Path("user_id") String user_id,            @Path("name") String name,            @Query("expand") String expand    );

POST方法：

 @FormUrlEncoded @POST("users/{user_id}/activities/{huodong_id}/bj") Call<ResponseBody> huodongSample(            @Path("user_id") String user_id,            @Path("huodong_id") String activity_id,            @Field("code") String code ); @Field:Post传递的参数 @FormUrlEncoded：如果POST请求，传递数据，必须要有

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统一处理的一些逻辑：

没有网络的处理：

Retrofit2.0无网状态处理：    无网会回调onFailure(Call<ResponseBody> call, Throwable t)方法，在该方法内部调用showFailure即可

public void showFailure( Throwable t) {        if(t.getMessage() != null && t.getMessage().startsWith("Failed to connect to")){            Log.d("lincoln","当前网络情况不稳定");        }    }

每次请求都添加Header或者Token：

    添加intercept即可

httpClient.addInterceptor(new Interceptor() {      @Override    public Response intercept(Interceptor.Chain chain) throws IOException {        Request original = chain.request();        Request request = original.newBuilder()            .header("User-Agent", "Your-App-Name")            .header("Accept", "application/vnd.yourapi.v1.full+json")            .method(original.method(), original.body())            .build();        return chain.proceed(request);    }}