首先列一下本篇文章要实现的功能
1.对服务器返回的数据进行预处理
2.请求时带上加载对话框，对话框取消同时取消请求
一下以个人公司返回数据为例，先上返回实体：
返回结果集基类
返回分页结果集基类
这里加一句如果返回分页数据也是要被BaseModel包裹的 BaseModel<PageModel<T>> T可以是所有对象这个你们应该懂得，分页的话T一般是List<你的对象>。
接下来举个例子
1.创建Retrofit 数据请求类
public class SystemApi {
//超时时间
public static final int DEFAULT_TIMEOUT = 10;
private static Retrofit provideRetrofit() {
OkHttpClient client = new OkHttpClient.Builder()
.connectTimeout(DEFAULT_TIMEOUT, TimeUnit.SECONDS)
.writeTimeout(DEFAULT_TIMEOUT, TimeUnit.SECONDS)
.readTimeout(DEFAULT_TIMEOUT, TimeUnit.SECONDS)
.build();
Retrofit retrofit = new Retrofit.Builder()
.baseUrl(BuildConfig.SERVER_HOST)//服务器项目地址
.addConverterFactory(JsonConverterFactory.create())//数据转换器，重写了下面有代码
.addCallAdapterFactory(RxJava2CallAdapterFactory.create())
.client(client)
.build();
return retrofit;
}
public static SystemApiService provideService() {
return provideRetrofit().create(SystemApiService.class);
}
}
2.数据转换器重写 实现指哪打哪的效果 我要什么结果就什么结果 不给就报错去吧！！！自带的不满足我,具体什么原因忘记了，反正就重写了。
public class JsonConverterFactory extends Converter.Factory {
private final Gson gson;
private JsonConverterFactory(Gson gson) {
if (gson == null)
throw new NullPointerException("gson == null");
this.gson = gson;
}
public static JsonConverterFactory create() {
return create(new Gson());
}
public static JsonConverterFactory create(Gson gson) {
return new JsonConverterFactory(gson);
}
@Override
public Converter<ResponseBody, ?> responseBodyConverter(Type type, Annotation[] annotations, Retrofit retrofit) {
TypeAdapter<?> adapter = gson.getAdapter(TypeToken.get(type));
return new JsonResponseBodyConverter<>(gson, adapter);
}
@Override
public Converter<?, RequestBody> requestBodyConverter(Type type, Annotation[] parameterAnnotations, Annotation[] methodAnnotations, Retrofit retrofit) {
TypeAdapter<?> adapter = gson.getAdapter(TypeToken.get(type));
return new JsonRequestBodyConverter<>(gson, adapter);
}
}
接下来实现 response和request转换
final class JsonRequestBodyConverter<T> implements Converter<T, RequestBody> {
private static final MediaType MEDIA_TYPE = MediaType.parse("application/json; charset=UTF-8");
private static final Charset UTF_8 = Charset.forName("UTF-8");
private final Gson gson;
private final TypeAdapter<T> adapter;
JsonRequestBodyConverter(Gson gson, TypeAdapter<T> adapter) {
this.gson = gson;
this.adapter = adapter;
}
@Override
public RequestBody convert(T value) throws IOException {
Buffer buffer = new Buffer();
Writer writer = new OutputStreamWriter(buffer.outputStream(), UTF_8);
JsonWriter jsonWriter = gson.newJsonWriter(writer);
adapter.write(jsonWriter, value);
jsonWriter.close();
return RequestBody.create(MEDIA_TYPE, buffer.readByteString());
}
}
public final class JsonResponseBodyConverter<T> implements Converter<ResponseBody, T> {
private final Gson gson;
private final TypeAdapter<T> adapter;
public final static String JSON_ERROR_STR = "数据结构异常!";
JsonResponseBodyConverter(Gson gson, TypeAdapter<T> adapter) {
this.gson = gson;
this.adapter = adapter;
}
@Override
public T convert(ResponseBody value) throws IOException {
String response = value.string();
if (BuildConfig.DEBUG) {
LogUtil.i("NetData", response);
}
try {
InputStream inputStream = new ByteArrayInputStream(response.getBytes());
Reader reader = new InputStreamReader(inputStream);
JsonReader jsonReader = gson.newJsonReader(reader);
T t = adapter.read(jsonReader);
return t;
} catch (Exception e) {
e.printStackTrace();
throw new RuntimeException(JSON_ERROR_STR);
} finally {
value.close();
}
}
}
到这里底层的数据请求转换就完成了，接下来我们用 RxJava2 方式去请求一个接口
public interface SystemApiService {
//去服务器验证账号是否存在，这里就不j介绍更多返回结果了，反正如果是登陆就返回Observable<BaseModel<UserInfo>>，
//如果是获取用户列表分页就是Observable<PageModel<List<UserInfo>>>
@FormUrlEncoded
@POST("authUserName")
Observable<BaseModel<Boolean>> authUserName(@FieldMap Map<String, Object> params);
}
接下来关键代码来了，结果预处理，不多少说直接上代码，我这前面不写文章的，写了你们也看不懂。
public class RxHelper {
/**
* 对结果进行预处理
*
* @param <T>
* @return
*/
public static final <T> ObservableTransformer<BaseModel<T>, T> applySchedulers() {
return new ObservableTransformer<BaseModel<T>, T>() {
@Override
public ObservableSource apply(Observable upstream) {
return upstream.flatMap(new Function<BaseModel<T>, Observable<T>>() {
@Override
public Observable<T> apply(BaseModel<T> result) {
if (result.ifSuccess()) {//检查是否掉接口成功了
return createData(result.getData());//成功，剥取我们要的数据，把BaseModel丢掉
} else {
return Observable.error(new Exception(result.getMsg()));//出错就返回服务器错误
}
}
}).subscribeOn(Schedulers.io())
.unsubscribeOn(Schedulers.io())
.observeOn(AndroidSchedulers.mainThread());
}
};
}
/**
* 创建成功的数据
*
* @param data
* @param <T>
* @return
*/
private static <T> Observable<T> createData(final T data) {
return Observable.create(new ObservableOnSubscribe<T>() {
@Override
public void subscribe(@NonNull ObservableEmitter<T> subscriber) throws Exception {
try {
subscriber.onNext(data);
subscriber.onComplete();
} catch (Exception e) {
subscriber.onError(e);
}
}
});
}
}
预处理就这么完了，我语言组织能力几乎为0，代码总看的来吧。
开始下一步，对话框显示。怎么弄，很简单继续看代码，要我描述做不到，最多代码给你们稍微注释下
//实现Observer类，把里面用不到的方法这里全处理掉 我们只处理结果 成功/失败
public abstract class RxSubscribe<T> implements Observer<T> {
private Context mContext;
private ProgressDialog dialog;
private String msg;
private boolean isShow = false;
public RxSubscribe(Context context) {
this.mContext = context;
}
public RxSubscribe(Context context, boolean isShow) {
this.mContext = context;
this.isShow = isShow;
msg = mContext.getString(R.string.dialog_message_loading);
}
public RxSubscribe(Context context, int msgResId) {
this.mContext = context;
isShow = true;
msg = mContext.getString(msgResId);
}
@Override
public void onComplete() {
if (isShow) {
if (dialog != null)
dialog.dismiss();
}
}
@Override
public void onSubscribe(@NonNull final Disposable d) {
if (isShow) {
dialog = new ProgressDialog(mContext);
dialog.setMessage(msg);
dialog.setIndeterminate(true);
dialog.setCanceledOnTouchOutside(false);
dialog.setOnCancelListener(new DialogInterface.OnCancelListener() {
@Override
public void onCancel(DialogInterface dialogInterface) {
// 对话框取消 直接停止执行请求
if (!d.isDisposed()) {
d.dispose();
}
}
});
dialog.show();
}
}
@Override
public void onNext(T t) {
_onNext(t);
}
@Override
public void onError(Throwable e) {
Log.i("onError",e.getMessage() );
//把底层的一些错误翻译一下用户看不来
if (e.getMessage() == null || e.getMessage().isEmpty()) {//未知错误
_onError(mContext.getString(R.string.error_unknown));
} else if (e.getMessage().contains("Failed to connect to") ||
e.getMessage().contains("failed to connect to")) {//连接服务器失败
if (!SystemUtil.isNetworkAvailable(mContext)) {//没网络
_onError(mContext.getString(R.string.error_bad_network));
} else {//真的没连接上服务器
_onError(mContext.getString(R.string.error_connect_server));
}
} else if (e.getMessage().contains("timed out") || e.getMessage().contains("timeout")) {
//超时了
_onError(mContext.getString(R.string.error_connect_server_timeout));
}else if (e.getMessage().contains("500")) {
//服务器内部错误
_onError(mContext.getString(R.string.error_connect_server_timeout));
} else {
_onError(e.getMessage());
}
if (isShow) {
if (dialog != null)
dialog.dismiss();
}
}
//成功
protected abstract void _onNext(T t);
//失败
protected abstract void _onError(String message);
}
基础的处理全部完成 最后我们的代码就是请求接口好了
/**
* Created by 王汗三
* Date 2017/7/14.
*/
public class RegisterPresenter extends BasePresenter {
private RegisterActivity activity;
public RegisterPresenter(RegisterActivity activity) {
super(activity);
this.activity = activity;
}
public void authUserName(String username) {
params.put("username", username);
SystemApi.provideService().authUserName(params).compose(RxHelper.<Boolean>applySchedulers()).subscribe(new RxSubscribe<Boolean>(activity, R.string.dialog_message_auth) {
@Override
protected void _onNext(Boolean isExits) {
if (isExits) {
IToast.show(context, "用户名已被别家熊孩子抢走了！");
} else {
activity.gotoNext();
}
}
@Override
protected void _onError(String message) {
IToast.show(context, message);
}
});
}
}
好了差不多完成了，最后给大家附带给上传文件的 看🐴 不多说
//上传文件加参数
@Multipart
@POST("PostThreads")
Observable<BaseModel<String>> uploadPost(@Part List<MultipartBody.Part> parts);
在带上个工具类
public class MultipartBodyUtil {
public static List<MultipartBody.Part> files2Parts(Map<String, String> fileMaps,
MediaType imageType) {
List<MultipartBody.Part> parts = new ArrayList<>();
for (Map.Entry<String, String> entry : fileMaps.entrySet()) {
File file = new File(entry.getValue());
RequestBody requestBody = RequestBody.create(imageType, file);
// 将RequestBody封装成MultipartBody.Part类型（同样是okhttp的）
MultipartBody.Part part = MultipartBody.Part.
createFormData(entry.getKey(), file.getName(), requestBody);
// 添加进集合
parts.add(part);
}
return parts;
}
/**
* 直接添加文本类型的Part到的MultipartBody的Part集合中
*
* @param parts Part集合
* @param key 参数名（name属性）
* @param value 文本内容
*/
public static void addTextPart(List<MultipartBody.Part> parts,
String key, String value) {
if(value!=null) {
RequestBody requestBody = RequestBody.create(MediaType.parse("text/plain;charset=utf-8"), value);
MultipartBody.Part part = MultipartBody.Part.createFormData(key, null, requestBody);
parts.add(part);
}
}
}
最后请求
/**
* Created by 王汗三
* Date 2017/2/7.
*/
public class SentPostPresenter extends BasePresenter {
SentPostActivity activity;
public SentPostPresenter(SentPostActivity activity) {
super(activity);
this.activity = activity;
}
public void uploadPost(String travelID, String forumId, String title, List<EditData> editDataList) {
Map<String, String> fileMaps = new HashMap<>();
for (int i = 0; i < editDataList.size(); i++) {
if (editDataList.get(i).getImagePath() != null && !editDataList.get(i).getImagePath().isEmpty()) {
fileMaps.put("file" + (i + 1), editDataList.get(i).getImagePath());
}
}
List<MultipartBody.Part> parts = MultipartBodyUtil.files2Parts(fileMaps, MediaType.parse("image/*;charset=utf-8"));
addBasePart(parts);//这个是我们项目必传参数 你们可以不用管
MultipartBodyUtil.addTextPart(parts, "eventId", travelID);
MultipartBodyUtil.addTextPart(parts, "forumId", forumId);
MultipartBodyUtil.addTextPart(parts, "title", title);
String content=new JsonResolver<List<EditData>>() {
}.toJson(editDataList);
MultipartBodyUtil.addTextPart(parts, "content", content);
SystemApi.provideService().uploadPost(parts).compose(RxHelper.<String>handleResult()).subscribe(new RxSubscribe<String>(activity, R.string.dialog_message_submit) {
@Override
protected void _onNext(String s) {
IToast.show(activity, "发表成功");
activity.setResult(Activity.RESULT_OK);
activity.finish();
}
@Override
protected void _onError(String message) {
Log.i("_onError",message);
IToast.show(activity, message);
}
});
}
}
这篇文章就到这里 别人说授人以鱼不如授人以渔，但是我只会授鱼，吃着鱼领悟吧！ 看不懂去看看Rxjava和泛型基础。
本文引用第三方库：
compile 'io.reactivex.rxjava2:rxjava:2.0.7'
compile 'io.reactivex.rxjava2:rxandroid:2.0.1'
compile 'com.squareup.retrofit2:adapter-rxjava2:2.3.0'
compile 'com.squareup.retrofit2:retrofit:2.3.0'
compile 'com.squareup.okio:okio:1.13.0'
compile 'com.squareup.okhttp3:okhttp:3.8.1'
compile 'com.google.code.gson:gson:2.8.0'
