java - 从第二个微调器位置获取字符串值

Question

我有两个微调器。

第一个微调器值是加德满都和巴克塔普尔，根据第一个微调器值，第二个微调器值被填满。

我的问题是，当我选择 Kathmandu 并从第二个微调器中选择第一项时，我得到了第二个微调器的第一项，这是我所期望的。

但是，当我首先从 Spinner 选择 Bhaktapur 或 Kathmandu 以下的任何项目时，然后在 Selecting first item position from second spinner 我得到第一个微调器值本身，它是 Bhaktapur 而不是“Bageswori”

但是，如果我选择第二个项目位置，那么没有问题，即我得到预期结果的“Balkot”。

所以问题在于，当我从第一个微调器中选择第一项位置下方的任何项目并从第二个微调器中选择第一项位置时。它返回第一个微调器的第一项值，而不是从第二个微调器中选择的值。

我的代码是

public class UploadBook extends AppCompatActivity implements AdapterView.OnItemSelectedListener {
   
    String item = "start";
    String condition = "start"; // for spinner
    FirebaseStorage storage;
    public Books b;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_upload_book);
        getSupportActionBar().setTitle("Upload Room Info");
        getSupportActionBar().setBackgroundDrawable(
                new ColorDrawable(Color.parseColor("#8abe50")));

        if (Build.VERSION.SDK_INT > Build.VERSION_CODES.LOLLIPOP)
            ActivityCompat.requestPermissions(UploadBook.this, new String[]{android.Manifest.permission.CAMERA, android.Manifest.permission.READ_EXTERNAL_STORAGE, android.Manifest.permission.WRITE_EXTERNAL_STORAGE}, 11);
        database = FirebaseDatabase.getInstance();
        dbreference = database.getReference();
        fauth = FirebaseAuth.getInstance();
        mStorageRef = FirebaseStorage.getInstance().getReference();
       
        b1 = (Button) findViewById(R.id.buttonPost);
        spinnerCountry = (Spinner) findViewById(R.id.spinnerCountry);
        //implementing OnItemSelectedListener (need to override the method)

        countryArray = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item);
        countryArray.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);

        spinnerCountry.setAdapter(countryArray);
        countryArray.add("Kathmandu");
        countryArray.add("Bhaktapur");
        countryArray.add("Lalitpur");
        countryArray.setNotifyOnChange(true);
        spinnerCountry.setSelection(0);
        spinnerDivision = (Spinner) findViewById(R.id.spinnerDivision);
        //implementing OnItemSelectedListener (need to override the method)
        spinnerDivision.setOnItemSelectedListener(this);
        spinnerCountry.setOnItemSelectedListener(this);
        divisionArray = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item);
        divisionArray.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);

        spinnerDivision.setAdapter(divisionArray);

        postButtonClick();


    @Override
    public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {

        item = parent.getItemAtPosition(position).toString();
        //first spinner item position
        int countrySpinnerPosition = spinnerCountry.getSelectedItemPosition();
        switch (countrySpinnerPosition){
            case 0:
                //fill data for second spinner
                fillKathmanduDivision();
                break;
            case 1:
                //fill data for second spinner
                fillBhaktapurDivision();
                break;          
        }
        //first spinner item position
    }

    private void fillKathmanduDivision() {
        divisionArray.clear();
        divisionArray.add("Anamnagar");
        divisionArray.add("Balaju");
        divisionArray.notifyDataSetChanged();
    }

    private void fillBhaktapurDivision() {
        divisionArray.clear();
        divisionArray.add("Bageswori");
        divisionArray.add("Balkot");
        divisionArray.notifyDataSetChanged();
    }

   b1.setOnClickListener(new View.OnClickListener() {

   }

   void postButtonClick() {

        b1.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
         
                     Toast.makeText(this, item, Toast.LENGTH_SHORT).show();
          } 
    }
 }

标签： javaandroidspinnerandroid-spinner

Answer 1

请使用以下代码：

private String country_id = "", city_id = "";
private ArrayList<String> country_array;

并用数据填充您的数组：

  for (int i = 0; i < items.getResponse().size(); i++) {
      String get_country_name = items.getResponse().get(i).getCode();
      country_array.add(get_country_name);
      }

现在为您的第一个微调器适配器：

   ArrayAdapter<String> country_spinnerArrayAdapter = new adapter_spinner(getActivity(), R.layout.spinner_header, country_array);
                                    country_spinnerArrayAdapter.setDropDownViewResource(R.layout.spinner_item);
                                    binding.etCountry.setAdapter(country_spinnerArrayAdapter);
                                    binding.etCountry.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
                                        @Override
                                        public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
                                            String selectedItemText = parent.getSelectedItem().toString();
                                            if (position > 0) {
                                                country_id = selectedItemText;
                                                city_id = "";
                                                Load_City(position - 1); // -1 to remove postion of the static country text
                                            }
                                        }

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

现在您的城市（第二个微调器）方法：

   private void Load_City(int postion) {
        ArrayList<String> city_array = new ArrayList<String>();
        city_array.add(getString(R.string.city));



        for (int i = 0; i < items.getResponse().get(postion).getCities().size(); i++) {
            String get_city_name = items.getResponse().get(postion).getCities().get(i).getName();
            city_array.add(get_city_name);

        }

        ArrayAdapter<String> country_spinnerArrayAdapter = new adapter_spinner(getActivity(), R.layout.spinner_header, city_array);
        country_spinnerArrayAdapter.setDropDownViewResource(R.layout.spinner_item);
        binding.etCity.setAdapter(country_spinnerArrayAdapter);

        binding.etCity.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
                String selectedItemText = parent.getSelectedItem().toString();
                if (position > 0) {
                    city_id = selectedItemText;
                }
            }

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

我希望这有帮助