基於另一個微調器填充微調器

Question

我是新手android 我想填充微調器2基於微調器1中選擇的值。 我能夠加載微調器2中的字段，但值沒有被選中。

這裏是我註冊的活動：

package com.example.ddubusmarg; 

import java.util.ArrayList; 
import java.util.List; 

import org.apache.http.NameValuePair; 
import org.apache.http.message.BasicNameValuePair; 
import org.json.JSONException; 
import org.json.JSONObject; 

import android.app.Activity; 
import android.app.ProgressDialog; 
import android.content.Intent; 
import android.os.AsyncTask; 
import android.os.Bundle; 
import android.util.Log; 
import android.view.View; 
import android.widget.AdapterView; 
import android.widget.AdapterView.OnItemSelectedListener; 
import android.widget.ArrayAdapter; 
import android.widget.Button; 
import android.widget.EditText; 
import android.widget.Spinner; 
import android.widget.Toast; 

public class SignUpActivity extends Activity implements OnItemSelectedListener { 

// Progress Dialog 
private ProgressDialog pDialog; 

JSONParser jsonParser = new JSONParser(); 
EditText inputName; 
EditText inputId; 
EditText inputPassword; 
EditText inputConfirmPassword; 
EditText inputPhoneNumber; 
// url to create new product 
private static String url_create_product = "http://192.168.1.6/registrationjson/insertnew.php"; 

// JSON Node names 
private static final String TAG_SUCCESS = "success"; 

@Override 
public void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_sign_up); 

     //spinner creation 
     Spinner spinner1 = (Spinner) findViewById(R.id.spinner1); 
     Spinner spinner2 = (Spinner) findViewById(R.id.spinner2); 
     Spinner spinner3 = (Spinner) findViewById(R.id.spinner3); 
     // Create an ArrayAdapter using the string array and a default spinner layout 
     ArrayAdapter<CharSequence> adapter1 = ArrayAdapter.createFromResource(this, 
       R.array.boarding_city, android.R.layout.simple_spinner_item); 
     ArrayAdapter<CharSequence> adapter2 = ArrayAdapter.createFromResource(this, 
       R.array.ahmedabad_routes, android.R.layout.simple_spinner_item); 
     ArrayAdapter<CharSequence> adapter3 = ArrayAdapter.createFromResource(this, 
       R.array.ahmedabad_RTO_boardings, android.R.layout.simple_spinner_item); 
     // Specify the layout to use when the list of choices appears 
     adapter1.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item); 
     adapter2.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item); 
     adapter3.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item); 
     // Apply the adapter to the spinner 
     spinner1.setAdapter(adapter1); 
     spinner2.setAdapter(adapter2); 
     spinner3.setAdapter(adapter3); 

     spinner1.setOnItemSelectedListener(this); 
     spinner2.setOnItemSelectedListener(this); 
     spinner3.setOnItemSelectedListener(this); 


    // Edit Text 
    inputName = (EditText) findViewById(R.id.editText1); // name 
    inputId = (EditText) findViewById(R.id.editText2); //id 
    inputPassword = (EditText) findViewById(R.id.editText3); //password 
    inputConfirmPassword = (EditText) findViewById(R.id.editText4); //confirm password 

    //inputCity = (EditText) findViewById(R.id.spinner); boarding city 
    inputPhoneNumber = (EditText) findViewById(R.id.editText5); // phone number 

    // Create button 
    Button btnCreateProduct = (Button) findViewById(R.id.button1); 

    // button click event 
    btnCreateProduct.setOnClickListener(new View.OnClickListener() { 

     @Override 
     public void onClick(View view) { 

      //confirming password 
      String name = inputName.getText().toString(); 
      String id = inputId.getText().toString(); 
      String password = inputPassword.getText().toString(); 
      String confirmPassword = inputConfirmPassword.getText().toString(); 
      String phoneNumber = inputPhoneNumber.getText().toString(); 

      if(name.equals("")||id.equals("")||password.equals("")||confirmPassword.equals("")||phoneNumber.equals("")) 
      { 
        Toast.makeText(getApplicationContext(), "Field(s) Vaccant", Toast.LENGTH_LONG).show(); 
        return; 
      } 
      // check if both password matches 
      if(phoneNumber.length() != 10) 
      { 
       Toast.makeText(getApplicationContext(), "PhoneNumber is not 10 digits", Toast.LENGTH_LONG).show(); 
       return; 
      } 
      if(!password.equals(confirmPassword)) 
      { 
       Toast.makeText(getApplicationContext(), "Password Does Not Matches", Toast.LENGTH_LONG).show(); 
       return; 
      } 
      else 
      { 
      // creating new product in background thread 
      new CreateNewProduct().execute(); 
      } 
     } 
    }); 
} 

/** 
* Background Async Task to Create new product 
* */ 
class CreateNewProduct extends AsyncTask<String, String, String> { 

    /** 
    * Before starting background thread Show Progress Dialog 
    * */ 
    @Override 
    protected void onPreExecute() { 
     super.onPreExecute(); 
     pDialog = new ProgressDialog(SignUpActivity.this); 
     pDialog.setMessage("Inserting Record..."); 
     pDialog.setIndeterminate(false); 
     pDialog.setCancelable(true); 
     pDialog.show(); 
    } 

    /** 
    * Creating product 
    * */ 

    //again spinner 


    protected String doInBackground(String... args) { 
     String name = inputName.getText().toString(); 
     name = name.toUpperCase(); 
     String id = inputId.getText().toString(); 
     id = id.toUpperCase(); 
     String password = inputPassword.getText().toString(); 

     Spinner spinner1 = (Spinner) findViewById(R.id.spinner1); 
     String city = spinner1.getSelectedItem().toString(); 

     Spinner spinner2 = (Spinner) findViewById(R.id.spinner2); 
     String route = spinner2.getSelectedItem().toString(); 

     Spinner spinner3 = (Spinner) findViewById(R.id.spinner3); 
     String boarding = spinner3.getSelectedItem().toString(); 


     String phoneNumber = inputPhoneNumber.getText().toString(); 

     // Building Parameters 
     List<NameValuePair> params = new ArrayList<NameValuePair>(); 
     params.add(new BasicNameValuePair("name", name)); 
     params.add(new BasicNameValuePair("id", id)); 
     params.add(new BasicNameValuePair("password", password)); 
     params.add(new BasicNameValuePair("city", city)); 
     params.add(new BasicNameValuePair("route", route)); 
     params.add(new BasicNameValuePair("boarding", boarding)); 
     params.add(new BasicNameValuePair("phoneNumber", phoneNumber)); 

     // getting JSON Object 
     // Note that create product url accepts POST method 
     JSONObject json = jsonParser.makeHttpRequest(url_create_product, 
       "GET", params); 

     // check log cat for response 
     Log.d("Create Response", json.toString()); 

     // check for success tag 
     try { 
      int success = json.getInt(TAG_SUCCESS); 

      if (success == 1) { 
       // successfully created product 
       Intent i = new Intent(getApplicationContext(), MainActivity.class); 
       startActivity(i); 

       // closing this screen 
       finish(); 
      } else { 
       // failed to create product 
      } 
     } catch (JSONException e) { 
      e.printStackTrace(); 
     } 

     return null; 
    } 

    /** 
    * After completing background task Dismiss the progress dialog 
    * **/ 
    protected void onPostExecute(String file_url) { 
     // dismiss the dialog once done 
     pDialog.dismiss(); 
    } 

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

    // An item was selected. You can retrieve the selected item using 
    // parent.getItemAtPosition(pos) 
    Spinner spinner1 = (Spinner) findViewById(R.id.spinner1); 
    spinner1.setOnItemSelectedListener(this); 

    //Spinner spinner2 = (Spinner) findViewById(R.id.spinner2); 
    //spinner2.setOnItemSelectedListener(this); 

    //setting spinner2 based on spinner1 
    String city= String.valueOf(spinner1.getSelectedItem()); 
    if(city.contentEquals("Ahmedabad")) { 

     Spinner spinner2 = (Spinner) findViewById(R.id.spinner2); 
     ArrayAdapter<CharSequence> adapter2 = ArrayAdapter.createFromResource(this, 
      R.array.ahmedabad_routes, android.R.layout.simple_spinner_item); 
     adapter2.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item); 
     adapter2.notifyDataSetChanged(); 
     spinner2.setAdapter(adapter2); 
     spinner2.setOnItemSelectedListener(this); 
    } 
    else if(city.contentEquals("Vadodara")) { 
     Spinner spinner2 = (Spinner) findViewById(R.id.spinner2); 
     ArrayAdapter<CharSequence> adapter2 = ArrayAdapter.createFromResource(this, 
      R.array.vadodara_routes, android.R.layout.simple_spinner_item); 

     adapter2.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item); 
     adapter2.notifyDataSetChanged(); 
     spinner2.setAdapter(adapter2); 
     spinner2.setOnItemSelectedListener(this); 
    } 


    Spinner spinner3 = (Spinner) findViewById(R.id.spinner3); 
    spinner3.setOnItemSelectedListener(this); 
} 

public void onNothingSelected(AdapterView<?> parent) { 
    // Another interface callback 
} 


} 

好心的幫助。

Answer 1

你已經在onCreate（）中註冊了一次監聽器，這已經足夠了。在onItemSelected回調中再次刪除註冊。

更多OOP風格的推薦方式是擁有不同的偵聽器對象。現在，因爲您的所有三個微調控制器都具有相同的偵聽器對象（活動本身），所以您需要在onItemSelected內部基於view.getId（）編寫一個切換案例，併爲每個案例執行不同的操作。

代碼看起來像下面

public void onItemSelected(AdapterView<?> parent, View view, 
     int pos, long id) { 
switch(view.getId()){ 
case R.id.spinner1id: 
//do spinner 1 action based on pos and id 
case R.id.spinner2id: 
//do spinner 2 action based on pos and id 
case R.id.spinner3id: 
//do spinner 3 action based on pos and id 
} 
}