Question

当我传递带有Retrofit2的对象时，我收到一个空响应。我收到带有URL的请求，但看到的内容为null。我不知道为什么...

public interface WeatherAPI {

    @GET("current.json")
    @Headers("Accept:application/json")
    Call<WeatherInfoResponse> getWeather(@Query("key") String key,@Query("q") String location);
}

    retrofit = new Retrofit.Builder()
            .baseUrl("https://api.apixu.com/v1/")
            .client(client)
            .addConverterFactory(ScalarsConverterFactory.create())
            .addConverterFactory(GsonConverterFactory.create())
            .build();
    weatherAPI =retrofit.create(WeatherAPI.class);
    weatherGET(KEY, locationCurrent);


}


void weatherGET(String key, final String  location){
    Call<WeatherInfoResponse> call = weatherAPI.getWeather(key,location);
    call.enqueue(new Callback<WeatherInfoResponse>() {
        @Override
        public void onResponse(Call <WeatherInfoResponse> call, Response<WeatherInfoResponse> response) {

            weatherInfoResponse =  response.body();

                Log.d("Temp",String.valueOf(weatherInfoResponse));


            Log.d("%%%%%","Entrada");
            float temp = weatherInfoResponse.getCurrent().getTemp_c();
        }
        @Override
        public void onFailure(Call<WeatherInfoResponse> call, Throwable t) {
            Log.d("%%%%%","Salida");

        }
    });
}

这是我的错误的LogCat

ava.lang.NullPointerException: Attempt to invoke virtual method 'float com.example.weatherapi.Current.getTemp_c()' on a null object reference
        at com.example.weatherapi.MainActivity$1.onResponse(MainActivity.java:65)

更新

我的POJO课，希望对您有帮助

public class WeatherInfoResponse { 
     public Location LocationObjectWeather;
     public Current CurrentObjectWeather; // Getter Methods public 
     Location getLocation() { return LocationObjectWeather; } public 
     Current getCurrent() { return CurrentObjectWeather; } // Setter 
    // Methods 
     public void setLocation(Location LocationObjectWeather) { 
         this.LocationObjectWeather = LocationObjectWeather;
     } 
     public void setCurrent(Current CurrentObjectWeather) { 
        this.CurrentObjectWeather = CurrentObjectWeather;
     }
 }

这是示例响应

    {
  "location": {
    "name": "Glasgow",
    "region": "Glasgow City",
    "country": "United Kingdom",
    "lat": 55.86,
    "lon": -4.25
  }
}

Any help would be appreciated, Thank you in advance

Answer 1

我建议您使用此在线服务生成 POJO 。有关信息，您的对象名称getter和setter应该与 JSON 中各个元素的名称相同。我假设您正在使用 Gson ，因为您正在使用GsonConverterFactory来解析响应。由于JSON响应不完整，但是我在这里发布了它的样子。您遇到的情况不一样，缺少一些元素。

样本响应：

   {
  "location": {
    "name": "Glasgow",
    "region": "Glasgow City",
    "country": "United Kingdom",
    "lat": 55.86,
    "lon": -4.25
  }
}

样本POJO应为以上响应应为：

import com.google.gson.annotations.Expose;
import com.google.gson.annotations.SerializedName;

public class Location {

@SerializedName("name")
@Expose
private String name;
@SerializedName("region")
@Expose
private String region;
@SerializedName("country")
@Expose
private String country;
@SerializedName("lat")
@Expose
private double lat;
@SerializedName("lon")
@Expose
private double lon;

public String getName() {
return name;
}

public void setName(String name) {
this.name = name;
}

public String getRegion() {
return region;
}

public void setRegion(String region) {
this.region = region;
}

public String getCountry() {
return country;
}

public void setCountry(String country) {
this.country = country;
}

public double getLat() {
return lat;
}

public void setLat(double lat) {
this.lat = lat;
}

public double getLon() {
return lon;
}

public void setLon(double lon) {
this.lon = lon;
}

}

-

import com.google.gson.annotations.Expose;
import com.google.gson.annotations.SerializedName;

public class Example {

@SerializedName("location")
@Expose
private Location location;

public Location getLocation() {
return location;
}

public void setLocation(Location location) {
this.location = location;
}

}

-

这是一本很好的书。希望对您有帮助。

http://www.jsonschema2pojo.org/

https://github.com/codepath/android_guides/wiki/Consuming-APIs-with-Retrofit

Answer 2

我已经使用pojo进行了转换。但是，当我导入它时，我在gson类和更多类中得到了一个错误，因此我不得不对其进行一些修改。这就是结果。名称都一样：

enter code here
public class WeatherInfoResponse {
public Location LocationObjectWeather;
public Current CurrentObjectWeather;

public Location getLocation() {
    return LocationObjectWeather;
}

public Current getCurrent() {
    return CurrentObjectWeather;
}
public void setLocation(Location LocationObjectWeather) {
    this.LocationObjectWeather = LocationObjectWeather;
}

public void setCurrent(Current CurrentObjectWeather) {
    this.CurrentObjectWeather = CurrentObjectWeather;
}

}

enter code here
package com.example.weatherapi;

public class Location {
private String name;
private String region;
private String country;
private float lat;
private float lon;
private String tz_id;
private float localtime_epoch;
private String localtime;
public String getName() {
    return name;
}

public String getRegion() {
    return region;
}

public String getCountry() {
    return country;
}

public float getLat() {
    return lat;
}

public float getLon() {
    return lon;
}

public String getTz_id() {
    return tz_id;
}

public float getLocaltime_epoch() {
    return localtime_epoch;
}

public String getLocaltime() {
    return localtime;
}

// Setter Methods

public void setName(String name) {
    this.name = name;
}

public void setRegion(String region) {
    this.region = region;
}

public void setCountry(String country) {
    this.country = country;
}

public void setLat(float lat) {
    this.lat = lat;
}

public void setLon(float lon) {
    this.lon = lon;
}

public void setTz_id(String tz_id) {
    this.tz_id = tz_id;
}

public void setLocaltime_epoch(float localtime_epoch) {
    this.localtime_epoch = localtime_epoch;
}

public void setLocaltime(String localtime) {
    this.localtime = localtime;
}
}


`package com.example.weatherapi;

public class Current {
private float last_updated_epoch;
private String last_updated;
private float temp_c;
private float temp_f;
private float is_day;
Condition ConditionObject;
private float wind_mph;
private float wind_kph;
private float wind_degree;
private String wind_dir;
private float pressure_mb;
private float pressure_in;
private float precip_mm;
private float precip_in;
private float humidity;
private float cloud;
private float feelslike_c;
private float feelslike_f;
private float vis_km;
private float vis_miles;
private float uv;
private float gust_mph;
private float gust_kph;
public float getLast_updated_epoch() {
    return last_updated_epoch;
}

public String getLast_updated() {
    return last_updated;
}

public float getTemp_c() {
    return temp_c;
}

public float getTemp_f() {
    return temp_f;
}

public float getIs_day() {
    return is_day;
}

public Condition getCondition() {
    return ConditionObject;
}

public float getWind_mph() {
    return wind_mph;
}

public float getWind_kph() {
    return wind_kph;
}

public float getWind_degree() {
    return wind_degree;
}

public String getWind_dir() {
    return wind_dir;
}

public float getPressure_mb() {
    return pressure_mb;
}

public float getPressure_in() {
    return pressure_in;
}

public float getPrecip_mm() {
    return precip_mm;
}

public float getPrecip_in() {
    return precip_in;
}

public float getHumidity() {
    return humidity;
}

public float getCloud() {
    return cloud;
}

public float getFeelslike_c() {
    return feelslike_c;
}

public float getFeelslike_f() {
    return feelslike_f;
}

public float getVis_km() {
    return vis_km;
}

public float getVis_miles() {
    return vis_miles;
}

public float getUv() {
    return uv;
}

public float getGust_mph() {
    return gust_mph;
}

public float getGust_kph() {
    return gust_kph;
}

// Setter Methods

public void setLast_updated_epoch(float last_updated_epoch) {
    this.last_updated_epoch = last_updated_epoch;
}

public void setLast_updated(String last_updated) {
    this.last_updated = last_updated;
}

public void setTemp_c(float temp_c) {
    this.temp_c = temp_c;
}

public void setTemp_f(float temp_f) {
    this.temp_f = temp_f;
}

public void setIs_day(float is_day) {
    this.is_day = is_day;
}

public void setCondition(Condition conditionObject) {
    this.ConditionObject = conditionObject;
}

public void setWind_mph(float wind_mph) {
    this.wind_mph = wind_mph;
}

public void setWind_kph(float wind_kph) {
    this.wind_kph = wind_kph;
}

public void setWind_degree(float wind_degree) {
    this.wind_degree = wind_degree;
}

public void setWind_dir(String wind_dir) {
    this.wind_dir = wind_dir;
}

public void setPressure_mb(float pressure_mb) {
    this.pressure_mb = pressure_mb;
}

public void setPressure_in(float pressure_in) {
    this.pressure_in = pressure_in;
}

public void setPrecip_mm(float precip_mm) {
    this.precip_mm = precip_mm;
}

public void setPrecip_in(float precip_in) {
    this.precip_in = precip_in;
}

public void setHumidity(float humidity) {
    this.humidity = humidity;
}

public void setCloud(float cloud) {
    this.cloud = cloud;
}

public void setFeelslike_c(float feelslike_c) {
    this.feelslike_c = feelslike_c;
}

public void setFeelslike_f(float feelslike_f) {
    this.feelslike_f = feelslike_f;
}

public void setVis_km(float vis_km) {
    this.vis_km = vis_km;
}

public void setVis_miles(float vis_miles) {
    this.vis_miles = vis_miles;
}

public void setUv(float uv) {
    this.uv = uv;
}

public void setGust_mph(float gust_mph) {
    this.gust_mph = gust_mph;
}

public void setGust_kph(float gust_kph) {
    this.gust_kph = gust_kph;
}
}

当我传递带有改造的对象时，我收到一个空响应

2 个答案: