改造 - 不断从 API 获得空体

Question

我已经尝试 Retrofit 一天半了，但 Retrofit 似乎不喜欢我的编程方法。

我收到 状态代码：200，没有错误，但正文始终为空。我尝试了不同的 APIs，所以我确定这是我的短代码中的一些架构错误。

注意： 到处使用 gitResult，为什么？我之前使用的是 Githubs API。

dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
compile 'com.android.support:appcompat-v7:22.2.1'
compile 'com.squareup.retrofit:retrofit:2.0.0-beta1'
compile 'com.squareup.okhttp:okhttp:2.4.0'
compile 'com.squareup.retrofit:converter-gson:2.0.0-beta1'

}

要明确：

Problem: body is always empty.

下面是我的代码的副本，我很感激任何建议。

public class MainActivity extends AppCompatActivity {

    private UserAdapter adapter ;
    List<Item> Users ;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        final ListView listView = (ListView) findViewById(R.id.listView);
        Users = new ArrayList<Item>();


        final ProgressDialog dialog = ProgressDialog.show(this, "", "loading...");


        RestClient.GitApiInterface service = RestClient.getClient();
        Call<GitResult> call = service.getUsersNamedTom();

        call.enqueue(new Callback<GitResult>() {
            @Override
            public void onResponse(Response<GitResult> response) {
                dialog.dismiss();
                Log.d("MainActivity", "Status Code = " + response.code());
                if (response.isSuccess()) {
                    // request successful (status code 200, 201)
                    GitResult result = response.body();
                    Log.d("MainActivity", "response = " + new Gson().toJson(result));
                    //Users = result.getItems();
                    Log.d("MainActivity", "Items = " + Users.size());
                    adapter = new UserAdapter(MainActivity.this, Users);
                    listView.setAdapter(adapter);
                } else {
                    // response received but request not successful (like 400,401,403 etc)
                    //Handle errors
                }
            }

            @Override
            public void onFailure(Throwable t) {
                dialog.dismiss();
            }
        });

..

public class GitResult {

    private int totalCount;
    private boolean incompleteResults;
    private List<Item> items = new ArrayList<Item>();

    public int getTotalCount() {
        return totalCount;
    }

    public void setTotalCount(int totalCount) {
        this.totalCount = totalCount;
    }

    public boolean isIncompleteResults() {
        return incompleteResults;
    }

    public void setIncompleteResults(boolean incompleteResults) {
        this.incompleteResults = incompleteResults;
    }

    public List<Item> getItems() {
        return items;
    }

    public void setItems(List<Item> items) {
        this.items = items;
    }
}


public final class ToStringConverter implements Converter<String> {

    @Override
    public String fromBody(ResponseBody body) throws IOException {
        return body.string();
    }

    @Override
    public RequestBody toBody(String value) {
        return RequestBody.create(MediaType.parse("text/plain"), value);
    }
}

..

public class RestClient {

    private static GitApiInterface gitApiInterface ;
    private static String baseUrl = "http://jsonplaceholder.typicode.com" ;

    public static GitApiInterface getClient() {
        if (gitApiInterface == null) {

            OkHttpClient okClient = new OkHttpClient();
            okClient.interceptors().add(new Interceptor() {
                @Override
                public Response intercept(Chain chain) throws IOException {
                    Response response = chain.proceed(chain.request());
                    return response;
                }
            });

            Retrofit client = new Retrofit.Builder()
                    .baseUrl(baseUrl)
                    .addConverter(String.class, new ToStringConverter())
                    .client(okClient)
                    .addConverterFactory(GsonConverterFactory.create())
                    .build();
            gitApiInterface = client.create(GitApiInterface.class);
        }
        return gitApiInterface ;
    }

    public interface GitApiInterface {

        @GET("/posts/1")
        Call<GitResult> getUsersNamedTom();

Answer 1

我遇到了同样的问题，问题是 JSON GSON 的映射有问题。 JSON 服务器发送的对象密钥与我使用的不匹配。

如果response Code是HTTP_OK但是response body是错误的，说明response解析有问题。仔细检查响应中的 JSON key/properties 是否与模型中的键映射匹配。

Answer 2

我尝试连接到 http://jsonplaceholder.typicode.com/posts/1 并得到响应：

   {
  "userId": 1,
  "id": 1,
  "title": "sunt aut facere repellat provident occaecati excepturi optio reprehenderit",
  "body": "quia et suscipit\nsuscipit recusandae consequuntur expedita et cum\nreprehenderit molestiae ut ut quas totam\nnostrum rerum est autem sunt rem eveniet architecto"
}

所以我认为您的 GitResult class 与 Server 的 Response 不匹配。我建议您将 GitResult class 更改为如下

public class GitResult {
    public int getUserId() { 
         return this.userId 
    }
    public int setUserId(int userId) { 
         this.userId = userId 
    }
    int userId;


    public int getId() { 
         return this.id 
    }
    public int setId(int id) { 
         this.id = id 
    }
    int id;


    public String getTitle() { 
         return this.title 
    }
    public String setTitle(String title) { 
         this.title = title 
    }
    String title;


    public String getBody() { 
         return this.body 
    }
    public String setBody(String body) { 
         this.body = body 
    }
    String body;

}

希望对您有所帮助！

Answer 3

我觉得问题可能出在这里：

.addConverter(String.class, new ToStringConverter())

尝试转换为 GitResult class 或这样尝试：

Retrofit client = new Retrofit.Builder()
                .baseUrl(baseUrl)
                .client(okClient)
                .addConverterFactory(GsonConverterFactory.create())
                .build();

改造 - 不断从 API 获得空体

Retrofit - Keep getting empty body from API

android

retrofit