How to get spinners selected item's id that comes from JSON

问题

I have two spinners that second spinner's value depend on the first spinner. every item in spinner has an id that came from JSON. Now, I want to get second spinner's item id. I get selected item's name but I need name and id of the selected item.

call.enqueue(new Callback<Map<String, ResponseJSON2>>()
{
        @Override
        public void onResponse
                (Call<Map<String, ResponseJSON2>> call, retrofit2.Response<Map<String, ResponseJSON2>> response) {
            responseJson = response.body();
            if (responseJson != null) {
                for (Map.Entry<String, ResponseJSON2> e : responseJson.entrySet()) {
                    provincesList.add(e.getKey());
                    for (Model c : e.getValue().getModel()) {
                        citiesList.add(c.getName());
                   }
               }
           }
          createAdapter();
      }
}

Thanks.

Model.java

public class Model {

    private String id;
    private String name;
    private String taxonomy;
    private String description;
    private String images;
    private String parent;
    //getter and setters

    @Override
    public String toString() {
        return "model{" +
                "id='" + id + '\'' +
                ", name='" + name + '\'' +
                ", taxonomy='" + taxonomy + '\'' +
                ", description='" + description + '\'' +
                ", images='" + images + '\'' +
                ", parent='" + parent + '\'' +
                '}';
    }
}

回答1:

You have to create a Listener for cities too:

spinner_city.setOnItemSelectedListener(citiesListener);

Then with this code you are able to get the cityId

private AdapterView.OnItemSelectedListener citiesListener = new AdapterView.OnItemSelectedListener() {
        @Override
        public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
            String citySelected = spinner_city.getItemAtPosition(position).toString();
            String provinceSelected = spinner_province.getSelectedItem().toString();
            for(Map.Entry<String, ResponseJSON> e : responseJson.entrySet())
            {
                if(e.getKey().equals(provinceSelected)){
                    for(City c : e.getValue().getCity()){
                        if(citySelected.equals(c.getCityName())){
                            tv_city_id.setText(String.format("City id for %s is %s", citySelected, c.getCityId()));
                        }
                    }
                }
            }
        }

        @Override
        public void onNothingSelected(AdapterView<?> parent) {

        }
    };

回答2:

can replace activity full code

public class MainActivity extends AppCompatActivity {

        private ApiInterface apiService;
        private Spinner spinner_province;
        private Spinner spinner_city;
        private ArrayAdapter<String> provinceAdapter;
        private ArrayAdapter<String> cityAdapter;
        private ArrayList<String> provincesList = new ArrayList<>();
        private ArrayList<String> citiesList = new ArrayList<>();
        private ArrayList<String> citiesIdList = new ArrayList<>();
        private Map<String, ResponseJSON> responseJson;


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

            initUI();

            apiService = ApiClient.getClient().create(ApiInterface.class);

            Call<Map<String, ResponseJSON>> call = apiService.getProvinceAndCity();
            call.enqueue(new Callback<Map<String, ResponseJSON>>() {
                @Override
                public void onResponse(Call<Map<String, ResponseJSON>> call, Response<Map<String, ResponseJSON>> response) {
                    responseJson = response.body();
                    for (Map.Entry<String, ResponseJSON> e : responseJson.entrySet()) {
                        provincesList.add(e.getKey());

                        for (City c : e.getValue().getCity()) {
                            citiesList.add(c.getCityName());
                        }
                    }
                    createAdapter();
                }

                @Override
                public void onFailure(Call<Map<String, ResponseJSON>> call, Throwable t) {

                }
            });
        }

        private void initUI() {
            spinner_city = findViewById(R.id.spinner_cities);
            spinner_province = findViewById(R.id.spinner_provinces);
        }

        private void createAdapter() {

            provinceAdapter = new ArrayAdapter<String>(this,
                    android.R.layout.simple_spinner_dropdown_item, provincesList);

            provinceAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
            spinner_province.setAdapter(provinceAdapter);
            cityAdapter = new ArrayAdapter<String>(this,
                    android.R.layout.simple_spinner_dropdown_item, citiesList);

            cityAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
            spinner_city.setAdapter(cityAdapter);

            spinner_province.setOnItemSelectedListener(provinceListener);

            spinner_city.setOnItemSelectedListener(citiesListener);


        }

        private AdapterView.OnItemSelectedListener provinceListener = new AdapterView.OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
                citiesList.clear();
                citiesIdList.clear();
                String provinceSelected = spinner_province.getItemAtPosition(position).toString();
                for (Map.Entry<String, ResponseJSON> e : responseJson.entrySet()) {
                    if (e.getKey().equals(provinceSelected)) {
                        for (City c : e.getValue().getCity()) {
                            citiesList.add(c.getCityName());
                            citiesIdList.add(c.getCityId());


                        }
                    }
                }
                cityAdapter.notifyDataSetChanged();
            }

            @Override
            public void onNothingSelected(AdapterView<?> parent) {

            }
        };


        private AdapterView.OnItemSelectedListener citiesListener = new AdapterView.OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
                int city_id = Integer.parseInt(citiesIdList.get(position));
                Log.i("your_city_id", String.valueOf(city_id));

            }

            @Override
            public void onNothingSelected(AdapterView<?> parent) {

            }
        };

    }

来源：https://stackoverflow.com/questions/52716627/how-to-get-spinners-selected-items-id-that-comes-from-json