1、添加依赖

//retrofit网络请求框架
  implementation 'com.squareup.retrofit2:retrofit:2.5.0'
  //retrofit添加Json解析返回数据
  implementation 'com.squareup.retrofit2:converter-gson:2.5.0'
  //retrofit添加Rxjava支持
  implementation 'com.jakewharton.retrofit:retrofit2-rxjava2-adapter:1.0.0'
  //rxjava框架
  implementation 'com.trello.rxlifecycle2:rxlifecycle-components:2.1.0'

2、创建 RetrofitFactory （单例模式）

• 创建 OkHttpClient

mOkHttpClient = new OkHttpClient().newBuilder()
        .readTimeout(mTimeOut, TimeUnit.SECONDS)
        .callTimeout(mTimeOut,TimeUnit.SECONDS)
        .writeTimeout(mTimeOut,TimeUnit.SECONDS)
        .addInterceptor(new URLInterceptor())//添加过滤器
        .retryOnConnectionFailure(true)//设置出现错误进行重新连接
    .build();

addInterceptor 添加过滤器，可根据需要进行过滤数据

public static class URLInterceptor implements Interceptor {
    private String TAG = "okhttp";

    @Override
    public Response intercept(Chain chain) throws IOException {
      Request request = chain.request()
                          .newBuilder()
                          .addHeader("Content-Type", "application/x-www-form-urlencoded; charset=UTF-8")//添加请求头
          //                .addHeader("Accept-Encoding", "gzip, deflate")
          //                .addHeader("Connection", "keep-alive")
          //                .addHeader("Accept", "*/*")
          //                .addHeader("Cookie", "add cookies here")
                          .build()
          ;

      Log.e(TAG,"request:" + request.toString());
      long t1 = System.nanoTime();
      okhttp3.Response response = chain.proceed(chain.request());
      long t2 = System.nanoTime();
      Log.e(TAG,String.format(Locale.getDefault(), "Received response for %s in %.1fms%n%s",
          response.request().url(), (t2 - t1) / 1e6d, response.headers()));
      okhttp3.MediaType mediaType = response.body().contentType();
      String content = response.body().string();
      Log.e(TAG, "response body:" + content);
      return response.newBuilder()
          .body(okhttp3.ResponseBody.create(mediaType, content))
          //                .header("Authorization", Your.sToken)
          .build();
      //return chain.proceed(request);
    }

• 创建Retrofit

public <T> T getService(Class<T> serviceClass) {
    if(mRetrofit == null ){
      mRetrofit = new Retrofit.Builder()
          .baseUrl(BASEURLS_DOMAIN)//添加域名
          .client(mOkHttpClient) // 添加mOkHttpClient
          .addConverterFactory(GsonConverterFactory.create())//
          .addCallAdapterFactory(RxJava2CallAdapterFactory.create())
          .build();
    }
    return mRetrofit.create(serviceClass);
  }  

https://ke.4399tech.com/ 本次实战项目的域名

3、封装BaseResponse与BaseObserver的封装

BaseResponse是个人自定义命名的一个类，主要用来对返回数据进行抽象。

BaseObserver是对返回数据的基础数据部分进行统一处理。

/**
 * 创建Base抽象类实现Observer
 */
public abstract class BaseObserver<T> implements Observer<BaseResponse<T>> {
    private static final String TAG = "BaseObserver";
    @Override
    public void onSubscribe(Disposable d) {
        Log.e(TAG, "onSubscribe: " );
    }
    @Override
    public void onNext(BaseResponse<T> response) {
        //在这边对 基础数据 进行统一处理  举个例子：
        if(response.getRes_code()==200){
            onSuccess(response.getResult());
        }else{
            onSuccess(null,response.getErr_msg(),response.getCode());
        }
    }
    @Override
    public void onError(Throwable e) {
        Log.e(TAG, "Throwable: " + e.getMessage());
           public abstract void onFailure(Throwable e, e.getMessage());
    }

    @Override
    public void onComplete() {
        Log.e(TAG, "onComplete: " );
    }

    public abstract void onSuccess(T demo);
    public abstract void onSuccess(T demo, String  errorMsg, int code);
    public abstract void onFailure(Throwable e,String errorMsg);

4、根据需求创建请求接口

@GET("/api/apiIndex/getGoodsList")
  Observable<BaseResponse<List<GoodsInfo>>> getGoodsList();

  //https://blog.csdn.net/jing_80/article/details/82931626
  @Multipart
  @POST("/api/apiuser/login")
  Observable<BaseResponse<String>> loginIn(@PartMap Map<String, RequestBody> requestBodyMap);

请求类型 @GET @POST

5、请求网络数据

RetrofitFactory.getInstance().getService(ApiUrl.class)
                .getRetrofit2()
                .subscribeOn(Schedulers.io())
                .observeOn(AndroidSchedulers.mainThread())
                .subscribe(new BaseObserver<Demo>(){
                    @Override
                    public void onSuccess(Demo demo) {
                        Log.e(TAG, "onSuccess: "+demo);
                    }
                    @Override
                    public void onFailure(Throwable e, String errorMsg) {
                        Log.e(TAG, "onFailure: "+errorMsg);
                    }
                });