Retrofit2与RxJava用法大全

Retrofit2是square公司出品的一个网络请求库，网上有很多相关的介绍。我很久以前都想去研究了，但一直都有各种事情耽搁，现在就让我们一起去捋一捋，这篇主要讲解Retrofit2与RxJava的基本用法。

get请求
post请求
文件上传
文件下载
开启日志拦截
与RxJava结合使用

什么是Retrofit2

官网是这么介绍的：

Retrofit adapts a Java interface to HTTP calls by using annotations on the declared methods to

define how requests are made。

我翻译的可能不准确，他的大概意思是说：Retrofit 是一个 java 接口类，以注解的方式用于 HTTP 网络请求。那下面我们一起来看看是怎么使用的？

使用前的配置

build.gradle 的 dependencies 添加：

    compile 'com.google.code.gson:gson:2.3.1'

    compile 'com.squareup.retrofit2:retrofit:2.0.0'

    compile 'com.squareup.retrofit2:converter-gson:2.0.0'

    compile 'com.squareup.okhttp3:logging-interceptor:3.2.0'

获取Retrofit实例

Retrofit retrofit = new Retrofit.Builder()

    .baseUrl("http://plus31.366ec.net/")

    .addConverterFactory(GsonConverterFactory.create())

    .build();

需要注意的是baseUrl添加的是地址的主域名。

申明RestService接口类

public interface RestService {

    @GET("/Route.axd?method=vast.Store.manager.list")

    Call<ResponseBody> getManagerData(@Query("StoreId") int id);

}

@GET 包含的是请求地址，是主域名之后的地址。举个例子，请求的

全地址：http://plus31.366ec.net/Route.axd?method=vast.Store.manager.list，

主域名为：http://plus31.366ec.net/

@GET包含的地址为：/Route.axd?method=vast.Store.manager.list

这样就完成了一个简单的@GET封装。

创建RestClient类

public class RestClient {

    private Retrofit mRetrofit;

    private static final String BASE_URL = "http://plus31.366ec.net/";

    private RestService mService;

    //构造方法

    public RestClient() {

        mRetrofit = new Retrofit.Builder()

                .baseUrl(BASE_URL)

                .addConverterFactory(GsonConverterFactory.create())

                .build();

        mService = mRetrofit.create(RestService.class);

    }

    public RestService getRectService() {

        if (mService != null) {

            return mService;

        }

        return null;

    }

}

这样就生成了一个简单的代理类，然后就可以进行相应请求了。

Get请求

public class SimpleGetActivity extends AppCompatActivity {

    private Button btnGet;

    private TextView tvResult;

    private RestClient mRestClient;

    @Override

    protected void onCreate(@Nullable Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_simple_get);

        btnGet = (Button) findViewById(R.id.btn_get);

        tvResult = (TextView) findViewById(R.id.tv_result);

        btnGet.setOnClickListener(new View.OnClickListener() {

            @Override

            public void onClick(View view) {

                //获取实例

                mRestClient = new RestClient();

                Call<ResponseBody> responseBodyCall = mRestClient.getRectService().getManagerData();

                //调用回调接口

                responseBodyCall.enqueue(new Callback<ResponseBody>() {

                    @Override

                    public void onResponse(Call<ResponseBody> call, Response<ResponseBody> response) {

                        try {

                            tvResult.setText(response.body().string());

                        } catch (IOException e) {

                            e.printStackTrace();

                        }

                    }

                    @Override

                    public void onFailure(Call<ResponseBody> call, Throwable t) {

                    }

                });

            }

        });

    }

}

一起来看看效果：

分析返回的 json数据，包含集合，那么我们可以进一步对接口返回值进行数据的封装。

BaseResponse类

public class BaseResponse<T> {

    @SerializedName("data")

    public List<T> managerList;

    @SerializedName("code")

    public int code;

    @SerializedName("message")

    public String message;

}

注意：BaseResponse类的字段，根据自己返回json数据新增或者删除。

根据返回的json集合，那么我们肯定有个实体类了。

Manager类

public class Manager {

    public int Id;

    public String UserName;

}

Manager 类你可以替换成你自己的实体类。

Get的进一步封装

@GET("/Route.axd?method=vast.Store.manager.list")

Call<BaseResponse<Manager>> getManagerDatas(@Query("StoreId") int id);

注意：我们这里对方法的返回值进行了一个修改Call<BaseResponse<Manager>>

来看看封装后的Activity类：

public class GetActivity extends AppCompatActivity {

    private Button btnGet;

    private RestClient mRestClient;

    private RecyclerView mRecyclerView;

    private BaseRecyclerAdapter<Manager> mAdapter;

    @Override

    protected void onCreate(@Nullable Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_get);

        btnGet = (Button) findViewById(R.id.btn_get);

        mRecyclerView = (RecyclerView) findViewById(R.id.rv);

        mRecyclerView.setLayoutManager(new LinearLayoutManager(this));

        btnGet.setOnClickListener(new View.OnClickListener() {

            @Override

            public void onClick(View view) {

                //获取实例

                mRestClient = new RestClient();

                Call<BaseResponse<Manager>> baseResponseCall = mRestClient.getRectService().getManagerDatas();

                baseResponseCall.enqueue(new Callback<BaseResponse<Manager>>() {

                    @Override

                    public void onResponse(Call<BaseResponse<Manager>> call, Response<BaseResponse<Manager>> response) {

                        //获取返回的集合数据

                        //response.body().managerList

                        mAdapter = new BaseRecyclerAdapter<Manager>(GetActivity.this, response.body().managerList, R.layout.rv_item) {

                            @Override

                            protected void convert(BaseViewHolder helper, Manager item) {

                                helper.setText(R.id.tv_item_text, item.UserName);

                            }

                        };

                        mRecyclerView.setAdapter(mAdapter);

                    }

                    @Override

                    public void onFailure(Call<BaseResponse<Manager>> call, Throwable t) {

                    }

                });

            }

        });

    }

}

来看看效果：

Get常用技巧

HashMap组装参数：

@GET("/Route.axd?method=vast.Store.manager.list")

    Call<BaseResponse<Manager>> getManagerDatas(@QueryMap HashMap<String, String> hm);

Get 请求就讲到这里了，下面一起来看看 Post请求。

Post请求

 @FormUrlEncoded

    @POST("/Route.axd?method=vast.Store.manager.list")

    Call<BaseResponse<Manager>> postManagerDatas(@Field("StoreId") int id);

@Field("StoreId") int id可以替换@Body，@Body你可以传入HashMap、实体 beans 等对象。

注意：以@Body上传参数，会默认加上Content-Type: application/json; charset=UTF-8的请求头，即以JSON格式请求，再以JSON格式响应。

单个文件上传

 @Multipart

    @POST("/UploadProduct.axd")

    Call<ResponseBody> uploadSimpleFile(@Part MultipartBody.Part file);

文件上传稍微复杂点，具体请看以下代码：

 File file = new File("/sdcard/", "a.xlxs");

    //file

    RequestBody requestFile = RequestBody.create(MediaType.parse("multipart/form-data"), file);

    //监听上传进度

    CountingRequestBody countingRequestBody = new CountingRequestBody(requestFile, new CountingRequestBody.Liste

        @Override

        public void onRequestProgress(long bytesWritten, long contentLength) {

            tvFile.setText("上传进度:" + contentLength + ":" + bytesWritten);

        }

    });

    MultipartBody.Part body =

            MultipartBody.Part.createFormData("file", file.getName(),countingRequestBody);

    mRestClient = new RestClient("http://192.168.4.111:686/");

    Call<ResponseBody> responseBodyCall = mRestClient.getRectService().uploadSimpleFile(body);

    responseBodyCall.enqueue(new Callback<ResponseBody>() {

        @Override

        public void onResponse(Call<ResponseBody> call, Response<ResponseBody> response) {

            tvFile.setText("上传成功");

        }

        @Override

        public void onFailure(Call<ResponseBody> call, Throwable t) {

            tvFile.setText(t.toString());

        }

    });

看看效果图：

多文件上传

@Multipart

@POST("/HpWens/ProgressDemos/")

Call<ResponseBody> uploads(@PartMap Map<String, RequestBody> params);

private void initData() {

        //保证文件按顺序上传 使用LinkedHashMap

        params = new LinkedHashMap<>();

        File file1 = new File("/sdcard/", "a.xlxs");

        final RequestBody requestBody1 = RequestBody.create(MediaType.parse("multipart/form-data"), file1);

        //监听上传进度

        CountingRequestBody countingRequestBody1 = new CountingRequestBody(requestBody1, new CountingRequestBody.Listener() {

            @Override

            public void onRequestProgress(long bytesWritten, long contentLength) {

                tvFile1.setText("上传进度:" + contentLength + ":" + bytesWritten);

            }

        });

        params.put("file\";filename=\"" + file1.getName(), countingRequestBody1);

        File file2 = new File("/sdcard/", "a.xlxs");

        RequestBody requestBody2 = RequestBody.create(MediaType.parse("multipart/form-data"), file2);

        //监听上传进度

        CountingRequestBody countingRequestBody2 = new CountingRequestBody(requestBody2, new CountingRequestBody.Listener() {

            @Override

            public void onRequestProgress(long bytesWritten, long contentLength) {

                tvFile2.setText("上传进度:" + contentLength + ":" + bytesWritten);

            }

        });

        params.put("file\";filename=\"" + file2.getName(), countingRequestBody2);

        mRestClient = new RestClient("http://192.168.4.111:686/");

        btnUpload.setOnClickListener(new View.OnClickListener() {

            @Override

            public void onClick(View view) {

                Call<ResponseBody> responseBodyCall = mRestClient.getRectService().uploadMultiFiles(params);

                responseBodyCall.enqueue(new Callback<ResponseBody>() {

                    @Override

                    public void onResponse(Call<ResponseBody> call, Response<ResponseBody> response) {

                        tvFile1.setText("上传成功");

                        tvFile2.setText("上传成功");

                    }

                    @Override

                    public void onFailure(Call<ResponseBody> call, Throwable t) {

                    }

                });

            }

        });

    }

在文章的后面我会附上源码，这里我就不在贴图了，具体请看demo

文件下载

@Streaming

@GET("/image/h%3D360/sign=86aee1fbf1deb48fe469a7d8c01e3aef/{filename}")

Call<ResponseBody> downFile(@Path("filename") String fileName);

处理方式基本和上面几种差不多：

public class DownFileActivity extends AppCompatActivity {

    private ImageView iv;

    private Button btnDown;

    private RestClient mRestClient;

    private String fileName;

    @Override

    protected void onCreate(@Nullable Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_down_file);

        iv = (ImageView) findViewById(R.id.iv);

        btnDown = (Button) findViewById(R.id.btn_down);

        mRestClient = new RestClient("http://d.hiphotos.baidu.com/");

        fileName = "b812c8fcc3cec3fd8757dcefd488d43f8794273a.jpg";

        btnDown.setOnClickListener(new View.OnClickListener() {

            @Override

            public void onClick(View view) {

                Call<ResponseBody> userCall = mRestClient.getRectService().downFile(fileName);

                userCall.enqueue(new Callback<ResponseBody>() {

                    @Override

                    public void onResponse(Call<ResponseBody> call, Response<ResponseBody> response) {

                        iv.setImageBitmap(BitmapFactory.decodeStream(response.body().byteStream()));

                        //saveFile(response.body().byteStream());

                    }

                    @Override

                    public void onFailure(Call<ResponseBody> call, Throwable t) {

                    }

                });

            }

        });

    }

    public void saveFile(InputStream is){

        try {

            String fn = Environment.getExternalStorageDirectory() + "/" + fileName;

            FileOutputStream fos = new FileOutputStream(fn);

            byte[] buf = new byte[];

            int len;

            while ((len = is.read(buf)) != -) {

                fos.write(buf, , len);

            }

            is.close();

            fos.close();

        } catch (Exception ex) {

        }

    }

}

效果一览：

开启OKHttp的日志拦截

开启日志后，会记录request和response的相关信息，非常实用，也非常强大，不知道是否是编码格式，我下载图片打印的全是乱码。

public void initRestClint(String baseUrl) {

    logging.setLevel(HttpLoggingInterceptor.Level.BODY);

    OkHttpClient.Builder httpClient = new OkHttpClient.Builder();

    httpClient.addInterceptor(logging);

    mRetrofit = new Retrofit.Builder()

            .baseUrl(baseUrl)

            .addConverterFactory(GsonConverterFactory.create())

            .addCallAdapterFactory(RxJavaCallAdapterFactory.create())

            .client(httpClient.build())

            .build();

    mService = mRetrofit.create(RestService.class);

}

类似这样的logcat日志：

Retrofit2与RxJava结合使用

添加库：

   compile 'io.reactivex:rxandroid:1.1.0'

    compile 'com.squareup.retrofit2:adapter-rxjava:2.0.0'

添加addCallAdapterFactory(RxJavaCallAdapterFactory.create())到Retrofit.Builder中：

mRetrofit = new Retrofit.Builder()

        .baseUrl(baseUrl)

        .addConverterFactory(GsonConverterFactory.create())

        .addCallAdapterFactory(RxJavaCallAdapterFactory.create())

        .client(httpClient.build())

        .build();

那么我们结合RxJava一起使用呢，下面我们一起来看一看：

@GET("/Route.axd?method=vast.Store.manager.list")

Observable<BaseResponse<Manager>> getManagers(@Query("StoreId") int id);

通过我们的观察是不是发现只有返回值发送了变化，Observable类型。

//获取实例

mRestClient = new RestClient();

mRestClient.getRectService().getManagers()

        .subscribeOn(Schedulers.io())

        .observeOn(AndroidSchedulers.mainThread())

        .subscribe(new Subscriber<BaseResponse<Manager>>() {

            @Override

            public void onCompleted() {

            }

            @Override

            public void onError(Throwable e) {

            }

            @Override

            public void onNext(BaseResponse<Manager> managerBaseResponse) {

            }

        });

RxJava支持链式写法，可以处理一些很复杂的问题。

源码地址