1、新建网络请求返回结果实例（根据自己的实际需要）

public class HttpResult {
    private int code;
    private String message;
    private T result;
    public int getCode() {
        returncode;    
    }
    public void setCode(intcode) {
        this.code = code;    
    }
    public String getMessage() {
        return message;    
    }
    public void setMessage(String message) {
        this.message = message;    
    }
    public T getResult() {
        return result;    
    }
    public void setResult(T result) {
        this.result = result;    
    }
}

2、创建网络请求工具类

public classHttpRequestUtils{
    public static finalString BASE_URL ="你网络请求地址前缀";
    private static finalintDEFAULT_TIMEOUT =10;
    private Retrofit retrofit;
    private RequestService requestService;
    /**
    * 创建私有构造方法，避免被外部实例化
    */
    private HttpRequestUtils() {
        //手动创建一个OkHttpClient并设置超时时间
        OkHttpClient.Builder builder =newOkHttpClient.Builder();        
        builder.connectTimeout(DEFAULT_TIMEOUT, TimeUnit.SECONDS);        
        retrofit =newRetrofit.Builder().client(builder.build())
                                .addConverterFactory(GsonConverterFactory.create())
                                .addCallAdapterFactory(RxJavaCallAdapterFactory.create())
                .baseUrl(BASE_URL)
                .build();        
        requestService = retrofit.create(RequestService.class);//网络请求API
    }
    /**
     * 在访问HttpRequestUtils时创建单例对象
     */
    private static classSingletonHolder{
        private static finalHttpRequestUtils INSTANCE =newHttpRequestUtils();    
    }
    /**    
     * 获取单利对象    
     *@return
     */
    public static HttpRequestUtils getInstance() {
        return SingletonHolder.INSTANCE;    
    }
    /**    * 获取请求对象    *@return*/
    public static RequestService getRequestService(){
        return getInstance().requestService;    
    }
    /**    * 设置观察者    *@paramo 被观察者    *@params 观察者    *@param 数据类型    */
    public void toSubscribe(Observable o, Subscriber s) {        
        o.subscribeOn(Schedulers.io()).unsubscribeOn(Schedulers.io())//在io线程中处理网络请求
         .observeOn(AndroidSchedulers.mainThread()).subscribe(s);//在主线程中处理数据
    }
}

3、处理请求结果

public class HttpResultFunctionimplementsFunc1<T> {
    @Override
    public T call(HttpResult tHttpResult) {
        if(tHttpResult.getCode() ==0) {
            thrownewApiException(ApiException.EXCEPTION_CODE1);//
        }
        returntHttpResult.getResult();    
    }
}

4、异常定义

public class ApiException extends RuntimeException{
    public  static final int EXCEPTION_CODE1=100;
    public  static final int EXCEPTION_CODE2=101;
    public ApiException(int resultCode) {
        this(getApiExceptionMessage(resultCode));    
    }
    public ApiException(String detailMessage) {
        super(detailMessage);    
    }
    private static String getApiExceptionMessage(intcode){
        String message ="";
        switch(code) {
            case EXCEPTION_CODE1:                
                message ="异常1";
                break;
            case EXCEPTION_CODE2:                
                message ="异常2";
                break;
                default:                
                message ="网络连接失败";        
        }
        return message;    
    }
}

5、定义请求API

public  interface RequestService {
    @POST("user/loginApi")    
    Observable loginApi(@Field("username") String username,@Field("password") String password,@Field("pushid") String pushid);
}

6、使用调用该登录方法

public void login( String username, String password,String pushid) {        
    Observable observable = HttpRequestUtils.getRequestService().loginApi(username, password,pushid).map(new HttpResultFunction());        
    HttpRequestUtils.getInstance().toSubscribe(observable,newSubscriber() {
        @Override
        public void onCompleted() {                
            Toast.makeText(OtherActivity.this,"完成",Toast.LENGTH_SHORT).show();            
        }
        @Override
        public void onError(Throwable throwable) {                
            Toast.makeText(OtherActivity.this,throwable.getMessage(),Toast.LENGTH_SHORT).show();            
        }
        @Override
        public void onNext(String s) {                
            Toast.makeText(OtherActivity.this,s,Toast.LENGTH_SHORT).show();            
        }        
    });    
}