How to pass objects from activity to fragments?

Question

I would like to pass objects (that I got through Retrofit) to fragments. I heard of 2 methods, but I have problems with both. I am trying to pass a FullForecast object to my fragments.

Use Parcelize. I implemented it on my class, but it conflicted with my constructor.

I heard I could pass a Json string from the activity to fragment and then convert it to an object once inside the fragment. However, I could not get the Json string from my Json call. I tried Call<ResponseBody>, and did response.body().toString(), but didnt get a Json string

Here is my code

repository.getWeatherForecast(place,
                object : Callback<FullForecast> {
                    override fun onFailure(call: Call<FullForecast>?, t: Throwable?) {
                        println("onFailure")
                    }

                    override fun onResponse(call: Call<FullForecast>?, response: Response<FullForecast>?) {
                        if (response != null && response.isSuccessful && response.body() != null) {

                            forecastObj = response.body() as FullForecast
                            // Try to get Json string here
                        }
                    }
                })

@JsonClass(generateAdapter = true)
data class FullForecast(@Json(name = "list")
                        val forecastList: List<WeatherForecast>) {
}

@JsonClass(generateAdapter = true)
data class WeatherForecast(@Json(name = "main")
                           val weatherDetail: WeatherDetail,

                           @Json(name = "weather")
                           val weatherIcon: List<WeatherIcon>,

                           @Json(name = "dt_txt")
                           val date: String) {
}

@JsonClass(generateAdapter = true)
data class Place(@Json(name = "main")
                 val weatherDetail: WeatherDetail,

                 @Json(name = "weather")
                 val weatherIcon: List<WeatherIcon>,

                 @Json(name = "sys")
                 val countryDetail: CountryDetail,

                 @Json(name = "dt_txt")
                 var forecastDate: String = "",

                 val name: String,

                 var placeIdentifier: String = "",

                 var lastUpdated: String = "") {
}

@JsonClass(generateAdapter = true)
data class CountryDetail(val country: String) {
}

@JsonClass(generateAdapter = true)
data class WeatherDetail(@Json(name = "temp")
                         val temperature: Double,
                         val temp_min: Double,
                         val temp_max: Double) {
}

@JsonClass(generateAdapter = true)
data class WeatherIcon(val icon: String) {
}

can you provide full `FullForecast` class? – GianhTran Jul 18 '18 at 08:36 — GianhTran, Jul 18 '18 at 08:36
@GianhTran done. That was actually the whole class – Zolly Jul 18 '18 at 08:43 — Zolly, Jul 18 '18 at 08:43
got it, please check my answer below – GianhTran Jul 18 '18 at 09:00 — GianhTran, Jul 18 '18 at 09:00

score 0 · Answer 1 · answered Jul 18 '18 at 08:29

0

Try EventBus to pass objects to fragments.

answered Jul 18 '18 at 08:29

code4rox

941
9
34

score 0 · Accepted Answer · answered Jul 18 '18 at 08:58

You should implement Parcelize as below

  @Parcelize
  @JsonClass(generateAdapter = true)
  data class FullForecast(@Json(name = "list")
  val forecastList: List<WeatherForecast>) : Parcelable {
  }

  @Parcelize
  @JsonClass(generateAdapter = true)
  data class WeatherForecast(@Json(name = "main")
  val weatherDetail: WeatherDetail,

      @Json(name = "weather")
      val weatherIcon: List<WeatherIcon>,

      @Json(name = "dt_txt")
      val date: String) : Parcelable {
  }

  @Parcelize
  @JsonClass(generateAdapter = true)
  data class Place(@Json(name = "main")
  val weatherDetail: WeatherDetail,

      @Json(name = "weather")
      val weatherIcon: List<WeatherIcon>,

      @Json(name = "sys")
      val countryDetail: CountryDetail,

      @Json(name = "dt_txt")
      var forecastDate: String = "",

      val name: String,

      var placeIdentifier: String = "",

      var lastUpdated: String = "") : Parcelable {
  }

  @Parcelize
  @JsonClass(generateAdapter = true)
  data class CountryDetail(val country: String) : Parcelable {
  }

  @Parcelize
  @JsonClass(generateAdapter = true)
  data class WeatherDetail(@Json(name = "temp")
  val temperature: Double,
      val temp_min: Double,
      val temp_max: Double) : Parcelable {
  }

  @Parcelize
  @JsonClass(generateAdapter = true)
  data class WeatherIcon(val icon: String) : Parcelable {
  }

If you face error:

This is a known bug in the IDE itself and you can ignore it, there’s nothing wrong with the code and it works as expected. You can keep track of the issue here.

score 0 · Answer 3 · answered Jul 18 '18 at 09:03

Follow this

Step 1: make your object implements Serializable

ex.public class Match implements Serializable { }

step 2: put your object to bundle and pass it to Activity or Fragment

ex.

Bundle args = new Bundle();
args.putSerializable("ARG_PARAM1", yourObject);

step 3: get your object form bundle like this

 yourObj = (Match) getArguments().getSerializable(ARG_PARAM1);

How to pass objects from activity to fragments?

3 Answers3