Android版&Kotlin版RxJava2+Retrofit2+OkHttp3的基础,kotlin开发网站
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@Override
public void onNext(MovieSubject movieSubject) {
mMovieAdapter.setMovies(movieSubject.subjects);
mMovieAdapter.notifyDataSetChanged();
}
});
5.加入RxJava的好处:
- 加入 RxJava 后的网络请求,返回不再是一个 Call ,而是一个 Observable。
- 在Activity / Fragment 中传入一个Subscriber 建立订阅关系,就可以在 onNext 中处理结果了。
- RxJava 的好处是帮我处理 线程之间的切换,我们可以在指定 订阅的在哪个线程,观察在哪个线程。
- 可以 通过操作符 进行数据变换。
- 整个过程都是链式的,简化逻辑。其中FlatMap 操作符 还可以解除多层嵌套的问题。
RxJava 很强大,能帮我处理很多复杂的场景,如果熟练使用的话,那么能提升我们的开发效率。
三,加入 OkHttp 配置:
通过OkHttpClient 可以配置很多东西,比如 链接超时时间,缓存,拦截器 等等。代码如下:
OkHttpClient.Builder builder = new OkHttpClient.Builder();
builder.connectTimeout(DEFAULT_TIME_OUT, TimeUnit.SECONDS);//连接 超时时间
builder.writeTimeout(DEFAULT_TIME_OUT,TimeUnit.SECONDS);//写操作 超时时间
builder.readTimeout(DEFAULT_TIME_OUT,TimeUnit.SECONDS);//读操作 超时时间
builder.retryOnConnectionFailure(true);//错误重连
// 添加公共参数拦截器
BasicParamsInterceptor basicParamsInterceptor = new BasicParamsInterceptor.Builder()
.addHeaderParam(“userName”,"")//添加公共参数
.addHeaderParam(“device”,"")
.build();
builder.addInterceptor(basicParamsInterceptor);
// 创建Retrofit
mRetrofit = new Retrofit.Builder()
.client(builder.build())
.addCallAdapterFactory(RxJava2CallAdapterFactory.create())
.addConverterFactory(GsonConverterFactory.create())
.baseUrl(ApiConfig.BASE_URL)
.build();
列举项目中用到的如下:
//项目中设置头信息
Interceptor headerInterceptor = new Interceptor() {
@Override
public Response intercept(Chain chain) throws IOException {
Request originalRequest = chain.request();
Request.Builder requestBuilder = originalRequest.newBuilder()
.addHeader(“Accept-Encoding”, “gzip”)
.addHeader(“Accept”, “application/json”)
.addHeader(“Content-Type”, “application/json; charset=utf-8”)
.method(originalRequest.method(), originalRequest.body());
requestBuilder.addHeader(“Authorization”, "Bearer " + BaseConstant.TOKEN);//添加请求头信息,服务器进行token有效性验证
Request request = requestBuilder.build();
return chain.proceed(request);
}
};
okHttpBuilder.addInterceptor(headerInterceptor);
//项目中创建Retrofit
retrofit = new Retrofit.Builder()
.client(okHttpBuilder.build())
.addConverterFactory(GsonConverterFactory.create())
.addCallAdapterFactory(RxJava2CallAdapterFactory.create())
.baseUrl(BASE_URL)
.build();
httpService = retrofit.create(HttpService.class);
封装篇
一,创建一个 统一生成接口实例的管理类 RetrofitServiceManager
创建了一个 RetrofitServiceManager 类,该类采用 单例模式,在 私有的 构造方法中,生成了 Retrofit 实例,并配置了OkHttpClient 和一些 公共配置。
提供了一个create()方法,生成 接口实例,接收 Class泛型。
代码如下:
public class RetrofitServiceManager {
private static final int DEFAULT_TIME_OUT = 5;//超时时间 5s
private static final int DEFAULT_READ_TIME_OUT = 10;
private Retrofit mRetrofit;
private RetrofitServiceManager(){
// 创建 OKHttpClient
OkHttpClient.Builder builder = new OkHttpClient.Builder();
builder.connectTimeout(DEFAULT_TIME_OUT, TimeUnit.SECONDS);//连接超时时间
builder.writeTimeout(DEFAULT_READ_TIME_OUT,TimeUnit.SECONDS);//写操作 超时时间
builder.readTimeout(DEFAULT_READ_TIME_OUT,TimeUnit.SECONDS);//读操作超时时间
// 添加公共参数拦截器
HttpCommonInterceptor commonInterceptor = new HttpCommonInterceptor.Builder()
.addHeaderParams(“paltform”,“android”)
.addHeaderParams(“userToken”,“1234343434dfdfd3434”)
.addHeaderParams(“userId”,“123445”)
.build();
builder.addInterceptor(commonInterceptor);
// 创建Retrofit
mRetrofit = new Retrofit.Builder()
.client(builder.build())
.addCallAdapterFactory(RxJava2CallAdapterFactory.create())
.addConverterFactory(GsonConverterFactory.create())
.baseUrl(ApiConfig.BASE_URL)
.build();
}
private static class SingletonHolder{
private static final RetrofitServiceManager INSTANCE = new RetrofitServiceManager();
}
/**
- 获取RetrofitServiceManager
- @return
*/
public static RetrofitServiceManager getInstance(){
return SingletonHolder.INSTANCE;
}
/**
- 获取对应的Service
- @param service Service 的 class
- @param
- @return
*/
public T create(Class service){
return mRetrofit.create(service);
}
}
接口实例Service都可以用这个来生成,代码如下:
mMovieService = RetrofitServiceManager.getInstance().create(MovieService.class);
二,创建接口,通过第一步获取实例
有了可以获取接口实例的方法,然后创建一个接口,代码如下:
public interface MovieService{
//获取豆瓣Top250 榜单
@GET(“top250”)
Observable getTop250(@Query(“start”) int start, @Query(“count”) int count);
@FormUrlEncoded
@POST("/x3/weather")
Call getWeather(@Field(“cityId”) String cityId, @Field(“key”) String key);
}
三,创建一个业务Loader ,如XXXLoder,获取Observable并处理相关业务
创建 Loader 的原因:每一个Api 都写一个接口很麻烦,因此就把 请求逻辑 封装在 一个业务Loader 里面,一个 Loader 里面可以处理多个Api 接口。代码如下:
public class MovieLoader extends ObjectLoader {
private MovieService mMovieService;
public MovieLoader(){
mMovieService = RetrofitServiceManager.getInstance().create(MovieService.class);
}
/**
- 获取电影列表
- @param start
- @param count
- @return
*/
public Observable<List> getMovie(int start, int count){
return observe(mMovieService.getTop250(start , count)).map(new Func1<MovieSubject, List>() {
@Override
public List call(MovieSubject movieSubject) {
return movieSubject.subjects;
}
});
}
public Observable getWeatherList(String cityId,String key){
return observe(mMovieService.getWeather(cityId , key)).map(new Func1<String , String>() {
@Override
public String call(String s) {
//可以处理对应的逻辑后在返回
return s;
}
});
}
public interface MovieService{
//获取豆瓣Top250 榜单
@GET(“top250”)
Observable getTop250(@Query(“start”) int start, @Query(“count”)int count);
@FormUrlEncoded
@POST("/x3/weather")
Call getWeather(@Field(“cityId”) String cityId, @Field(“key”) String key);
}
}
创建一个MovieLoader,构造方法中生成了mHttpService,而 Service 中可以定义和业务相关的多个api,比如:例子中的HttpService中,
可以定义和电影相关的多个api,获取电影列表、获取电影详情、搜索电影等api,就不用定义多个接口了。
MovieLoader 是从 ObjectLoader 中继承下来的,ObjectLoader 提取了一些公共的操作。代码如下:
/**
- 将一些重复的操作提出来,放到父类以免Loader 里每个接口都有重复代码
/
public class ObjectLoader {
/* - @param observable
- @param
- @return
*/
protected Observable observe(Observable observable){
return observable
.subscribeOn(Schedulers.io())
.unsubscribeOn(Schedulers.io())
.observeOn(AndroidSchedulers.mainThread());
}
}
四,Activity/Fragment 中的调用
创建Loader实例:
mMovieLoader = new MovieLoader();
通过Loader 调用方法获取结果,代码如下:
/**
- 获取电影列表
*/
private void getMovieList(){
mMovieLoader.getMovie(0,10).subscribe(new Action1<List>() {
@Override
public void call(List movies) {
mMovieAdapter.setMovies(movies);
mMovieAdapter.notifyDataSetChanged();
}
}, new Action1() {
@Override
public void call(Throwable throwable) {
Log.e(“TAG”,“error message:”+throwable.getMessage());
}
});
}
五,统一处理结果和错误
1.统一处理请求结果:
现实项目中,所有接口的返回结果都是同一格式,如:
{
“status”: 200,
“message”: “成功”,
“data”: {}
}
在请求api 接口的时候,只关心想要的数据,也就上面的 data{ },其他的东西不太关心,请求失败 的时候可以根据 status 判断进行 错误处理。
包装返回结果:首先需要根据服务端定义的 JSON 结构创建一个 BaseResponse 类,代码如下:
/**
- 网络请求结果 基类
*/
public class BaseResponse {
public int status;
public String message;
public T data;
public boolean isSuccess(){
return status == 200;
}
}
有了统一的格式数据后,我们需要 剥离出data{ }返回给 上层调用者,创建一个 PayLoad 类,代码如下:
/**
- 剥离 最终数据
*/
public class PayLoad implements Func1<BaseResponse{
@Override
public T call(BaseResponse tBaseResponse) {//获取数据失败时,包装一个Fault 抛给上层处理错误
if(!tBaseResponse.isSuccess()){
throw new Fault(tBaseResponse.status,tBaseResponse.message);
}
return tBaseResponse.data;
}
}
PayLoad 继承自 Func1,接收一个BaseResponse , 就是接口返回的 JSON 数据结构,返回的是 T,就是data{ },判断是否请求成功,请求成功 返回Data,请求失败 包装成一个 Fault 返回给上层统一处理错误。
在Loader类里面获取结果后,通过map 操作符剥离数据。代码如下:
public Observable<List> getMovie(int start, int count){
return observe(mMovieService.getTop250(start,count))
.map(new PayLoad<BaseResponse<List>());
}
2.统一处理错误:
在PayLoad 类里面,请求失败时,抛出了一个Fault 异常给上层,我在Activity/Fragment 中拿到这个异常,然后判断错误码,进行异常处理。在onError () 中添加。
对应 错误码 处理 相应的错误,代码如下:
public void call(Throwable throwable) {
Log.e(“TAG”,“error message:”+throwable.getMessage());
if(throwable instanceof Fault){
Fault fault = (Fault) throwable;
if(fault.getErrorCode() == 404){
//错误处理
}else if(fault.getErrorCode() == 500){
//错误处理
}else if(fault.getErrorCode() == 501){
//错误处理
}
}
}
六,添加公共参数
实际项目中,每个接口都有一些基本的相同的参数,我们称之为公共参数,比如:userId、userToken、userName、deviceId等等,我们不必每个接口都去写,可以写一个拦截器,在拦截器里面拦截请求,为每个请求都添加相同的公共参数。
拦截器代码如下:
/*
- 拦截器
- 向请求头里添加公共参数
*/
public class HttpCommonInterceptor implements Interceptor {
private Map<String,String> mHeaderParamsMap = new HashMap<>();
public HttpCommonInterceptor() {
}
@Override
public Response intercept(Chain chain) throws IOException {
Log.d(“HttpCommonInterceptor”,“add common params”);
Request oldRequest = chain.request();
// 添加新的参数,添加到url 中
/HttpUrl.Builder authorizedUrlBuilder = oldRequest.url().newBuilder()
.scheme(oldRequest.url().scheme())
.host(oldRequest.url().host());/
// 新的请求
Request.Builder requestBuilder = oldRequest.newBuilder();
requestBuilder.method(oldRequest.method(), oldRequest.body());
//添加公共参数,添加到header中
if(mHeaderParamsMap.size() > 0){
for(Map.Entry<String,String> params:mHeaderParamsMap.entrySet()){
requestBuilder.header(params.getKey(),params.getValue(
));
}
}
Request newRequest = requestBuilder.build();
return chain.proceed(newRequest);
}
public static class Builder{
HttpCommonInterceptor mHttpCommonInterceptor;
public Builder(){
mHttpCommonInterceptor = new HttpCommonInterceptor();
}
public Builder addHeaderParams(String key, String value){
mHttpCommonInterceptor.mHeaderParamsMap.put(key,value);
return this;
}
public Builder addHeaderParams(String key, int value){
return addHeaderParams(key, String.valueOf(value));
}
public Builder addHeaderParams(String key, float value){
return addHeaderParams(key, String.valueOf(value));
}
public Builder addHeaderParams(String key, long value){
return addHeaderParams(key, String.valueOf(value));
}
public Builder addHeaderParams(String key, double value){
return addHeaderParams(key, String.valueOf(value));
}
public HttpCommonInterceptor build(){
return mHttpCommonInterceptor;
}
}
}
以上就是添加公共参数的拦截器,在 RetrofitServiceManager 类里面加入OkHttpClient 配置就好了。
代码如下:
// 添加公共参数拦截器
HttpCommonInterceptor commonInterceptor = new HttpCommonInterceptor.Builder()
.addHeaderParams(“paltform”,“android”)
.addHeaderParams(“userToken”,“1234343434dfdfd3434”)
.addHeaderParams(“userId”,“123445”)
.build();
builder.addInterceptor(commonInterceptor);
项目使用篇 ----->插入广告!本项目来源于金融研习社App,金融理财类的在线教育
项目是基于RxJava1
1.引入依赖:
compile ‘com.google.code.gson:gson:2.6.2’//导入Gson 库
//导入RxJava 和 RxAndroid
compile ‘io.reactivex.rxjava2:rxandroid:2.0.2’
compile ‘io.reactivex.rxjava2:rxjava:2.x.y’
compile ‘com.squareup.retrofit2:retrofit:2.3.0’//导入retrofit
compile ‘com.squareup.retrofit2:converter-gson:2.3.0’//转换器,请求结果转换成Model
compile ‘com.squareup.retrofit2:adapter-rxjava2:2.3.0’//配合Rxjava 使用
compile ‘com.squareup.okhttp3:logging-interceptor:3.8.1’//添加HttpLoggingInterceptor进行调试
2.创建一个HttpService接口:
public interface HttpService {
/**
- 获取用户详细资料
*/
@POST(“api/XXX/GetUserAllDetails”)
Observable getUserAllDetails(@Body GetUserAllDetailsRequestBean bean);
/**
- @param apkUrl 下载地址
*/
@GET()
@Streaming
Call downloadNewApk(@Url String apkUrl);
/**
- 获取推广大使分享图片
*/
@GET(“api/XXX/InvitedImage”)
Observable getInvitedImage(@QueryMap Map<String, Object> map);
}
3.创建http请求类,并在里面初始化并配置Retrofit和OkHttp:
public class HttpMethods {
public String TAG = “HttpMethods”;
public static final String CACHE_NAME = “xxx”;
public static String BASE_URL = URLConstant.BASE_URL;
private static final int DEFAULT_CONNECT_TIMEOUT = 30;
private static final int DEFAULT_WRITE_TIMEOUT = 30;
private static final int DEFAULT_READ_TIMEOUT = 30;
private Retrofit retrofit;
private HttpService httpService;
/**
- 请求失败重连次数
*/
private int RETRY_COUNT = 0;
private OkHttpClient.Builder okHttpBuilder;
//构造方法私有
private HttpMethods() {
//手动创建一个OkHttpClient并设置超时时间
okHttpBuilder = new OkHttpClient.Builder();
/**
- 设置缓存
*/
File cacheFile = new File(ApplicationContext.context.getExternalCacheDir(), CACHE_NAME);
Cache cache = new Cache(cacheFile, 1024 * 1024 * 50);
Interceptor cacheInterceptor = new Interceptor() {
@Override
public Response intercept(Chain chain) throws IOException {
Request request = chain.request();
if (!NetUtil.isNetworkConnected()) {
request = request.newBuilder()
.cacheControl(CacheControl.FORCE_CACHE)
.build();
}
Response response = chain.proceed(request);
if (!NetUtil.isNetworkConnected()) {
int maxAge = 0;
// 有网络时 设置缓存超时时间0个小时
response.newBuilder()
.header(“Cache-Control”, “public, max-age=” + maxAge)
.removeHeader(CACHE_NAME)// 清除头信息,因为服务器如果不支持,会返回一些干扰信息,不清除下面无法生效
.build();
} else {
// 无网络时,设置超时为4周
int maxStale = 60 * 60 * 24 * 28;
response.newBuilder()
.header(“Cache-Control”, “public, only-if-cached, max-stale=” + maxStale)
.removeHeader(CACHE_NAME)
.build();
}
return response;
}
};
okHttpBuilder.cache(cache).addInterceptor(cacheInterceptor);
/**
- 设置头信息
*/
Interceptor headerInterceptor = new Interceptor() {
@Override
public Response intercept(Chain chain) throws IOException {
Request originalRequest = chain.request();
Request.Builder requestBuilder = originalRequest.newBuilder()
.addHeader(“Accept-Encoding”, “gzip”)
.addHeader(“Accept”, “application/json”)
.addHeader(“Content-Type”, “application/json; charset=utf-8”)
.method(originalRequest.method(), originalRequest.body());
requestBuilder.addHeader(“Authorization”, "Bearer " + BaseConstant.TOKEN);//添加请求头信息,服务器进行token有效性验证
Request request = requestBuilder.build();
return chain.proceed(request);
}
};
okHttpBuilder.addInterceptor(headerInterceptor);
// if (BuildConfig.DEBUG) {
HttpLoggingInterceptor loggingInterceptor = new HttpLoggingInterceptor(new HttpLoggingInterceptor.Logger() {
@Override
public void log(String message) {
Logger.d(message);
}
});
loggingInterceptor.setLevel(HttpLoggingInterceptor.Level.BODY);
//设置 Debug Log 模式
okHttpBuilder.addInterceptor(loggingInterceptor);
// }
/**
- 设置超时和重新连接
*/
okHttpBuilder.connectTimeout(DEFAULT_CONNECT_TIMEOUT, TimeUnit.SECONDS);
okHttpBuilder.readTimeout(DEFAULT_WRITE_TIMEOUT, TimeUnit.SECONDS);
okHttpBuilder.writeTimeout(DEFAULT_READ_TIMEOUT, TimeUnit.SECONDS);
//错误重连
okHttpBuilder.retryOnConnectionFailure(true);
retrofit = new Retrofit.Builder()
.client(okHttpBuilder.build())
.addConverterFactory(GsonConverterFactory.create())//json转换成JavaBean
.addCallAdapterFactory(RxJava2CallAdapterFactory.create())
.baseUrl(BASE_URL)
.build();
httpService = retrofit.create(HttpService.class);
}
//在访问HttpMethods时创建单例
private static class SingletonHolder {
private static final HttpMethods INSTANCE = new HttpMethods();
}
//获取单例
public static HttpMethods getInstance() {
return SingletonHolder.INSTANCE;
}
/**
- 获取retrofit
*/
public Retrofit getRetrofit() {
return retrofit;
}
public void changeBaseUrl(String baseUrl) {
retrofit = new Retrofit.Builder()
.client(okHttpBuilder.build())
.addConverterFactory(GsonConverterFactory.create())
.addCallAdapterFactory(RxJava2CallAdapterFactory.create())
.baseUrl(baseUrl)
.build();
httpService = retrofit.create(HttpService.class);
}
/**
- 获取httpService
*/
public HttpService getHttpService() {
der {
private static final HttpMethods INSTANCE = new HttpMethods();
}
//获取单例
public static HttpMethods getInstance() {
return SingletonHolder.INSTANCE;
}
/**
- 获取retrofit
*/
public Retrofit getRetrofit() {
return retrofit;
}
public void changeBaseUrl(String baseUrl) {
retrofit = new Retrofit.Builder()
.client(okHttpBuilder.build())
.addConverterFactory(GsonConverterFactory.create())
.addCallAdapterFactory(RxJava2CallAdapterFactory.create())
.baseUrl(baseUrl)
.build();
httpService = retrofit.create(HttpService.class);
}
/**
- 获取httpService
*/
public HttpService getHttpService() {
标签:return,String,Kotlin,Builder,OkHttp3,build,new,Retrofit2,public 来源: https://blog.csdn.net/m0_66264169/article/details/122619864