android - 如何使用异步任务动态设置微调器中的内容？

Question

我是安卓新手。我正在尝试从数据库中获取微调器中的数据。但是我不知道为什么我的列表没有在微调器中设置。

我的代码是

public class AddBasicDetail extends Fragment implements AdapterView.OnItemSelectedListener {

    // array list for spinner adapter
    private ArrayList<State> categoriesList;
    ProgressDialog pDialog;

    Spinner sp_state;
    // API urls
    // Url to create new category
    private String URL_NEW_CATEGORY = "http://mandirdekhoo.com/app/md_eng/state.php";

    public AddBasicDetail() {
        // Required empty public constructor
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        View v = inflater.inflate(R.layout.add_basic_detail, container, false);

        sp_state = (Spinner) v.findViewById(R.id.sp_state);
        categoriesList = new ArrayList<State>();

        // spinner item select listener
        //sp_state.setOnItemSelectedListener((AdapterView.OnItemSelectedListener) getActivity());

        new GetCategories().execute();

        return v;
    }

    /**
    * Adding spinner data
    * */
    private void populateSpinner() {
         List<String> lables = new ArrayList<String>();

         //txtCategory.setText("");

         for (int i = 0; i < categoriesList.size(); i++) {
              lables.add(categoriesList.get(i).getName());
         }

         // Creating adapter for spinner
         ArrayAdapter<String> spinnerAdapter = new ArrayAdapter<String>(getContext(),
                        android.R.layout.simple_spinner_item, lables);

         // Drop down layout style - list view with radio button
         spinnerAdapter                           .setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);

         // attaching data adapter to spinner
         sp_state.setAdapter(spinnerAdapter);
    }

    /**
    * Async task to get all food categories
    * */
    private class GetCategories extends AsyncTask<Void, Void, Void> {

        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            pDialog = new ProgressDialog(getContext());
            pDialog.setMessage("Fetching food categories..");
            pDialog.setCancelable(false);
            pDialog.show();

        }

        @Override
        protected Void doInBackground(Void... arg0) {
            ServiceHandler jsonParser = new ServiceHandler();
            String json = jsonParser.makeServiceCall(URL_NEW_CATEGORY, ServiceHandler.GET);

            Log.e("Response: ", "> " + json);

            if (json != null) {

                try {
                    JSONObject jsonObj = new JSONObject(json);
                    Log.e("my response: ", "> " + jsonObj);
                    if (jsonObj != null) {
                        JSONArray categories = jsonObj                                            .getJSONArray("result");

                                for (int i = 0; i < categories.length(); i++) {
                                    JSONObject catObj = (JSONObject) categories.get(i);
                                    State cat = new State(catObj.getInt("id"),
                                            catObj.getString("state_name"));
                                    categoriesList.add(cat);
                                }
                            }

                        } catch (JSONException e) {
                            e.printStackTrace();
                        }

                    } else {
                        Log.e("JSON Data", "Didn't receive any data from server!");
                    }

                    return null;
                }

                @Override
                protected void onPostExecute(Void result) {
                    super.onPostExecute(result);
                    if (pDialog.isShowing())
                        pDialog.dismiss();
                    //populateSpinner();
                }

            }
            @Override
            public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
                    Toast.makeText(
                        getContext(),
                        parent.getItemAtPosition(position).toString() + " Selected" ,
                        Toast.LENGTH_LONG).show();

            }

            @Override
            public void onNothingSelected(AdapterView<?> arg0) {
            }
        }

我的服务处理器类是

public class ServiceHandler {

    static InputStream is = null;
    static String response = null;
    public final static int GET = 1;
    public final static int POST = 2;

    public ServiceHandler() {

    }

    /**
     * Making service call
     * @url - url to make request
     * @method - http request method
     * */
    public String makeServiceCall(String url, int method) {
        return this.makeServiceCall(url, method, null);
    }

    /**
     * Making service call
     * @url - url to make request
     * @method - http request method
     * @params - http request params
     * */
    public String makeServiceCall(String url, int method,
                                  List<NameValuePair> params) {
        try {
            // http client
            DefaultHttpClient httpClient = new DefaultHttpClient();
            HttpEntity httpEntity = null;
            HttpResponse httpResponse = null;

            // Checking http request method type
            if (method == POST) {
                HttpPost httpPost = new HttpPost(url);
                // adding post params
                if (params != null) {
                    httpPost.setEntity(new UrlEncodedFormEntity(params));
                }

                httpResponse = httpClient.execute(httpPost);

            } else if (method == GET) {
                // appending params to url
                if (params != null) {
                    String paramString = URLEncodedUtils
                            .format(params, "utf-8");
                    url += "?" + paramString;
                }
                HttpGet httpGet = new HttpGet(url);

                httpResponse = httpClient.execute(httpGet);

            }
            httpEntity = httpResponse.getEntity();
            is = httpEntity.getContent();

        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

        try {
            BufferedReader reader = new BufferedReader(new InputStreamReader(
                    is, "UTF-8"), 8);
            StringBuilder sb = new StringBuilder();
            String line = null;
            while ((line = reader.readLine()) != null) {
                sb.append(line + "\n");
            }
            is.close();
            response = sb.toString();
        } catch (Exception e) {
            Log.e("Buffer Error", "Error: " + e.toString());
        }

        return response;

    }

}

和

public class State {

    private int id;
    private String name;

    public State(){}

    public State(int id, String name){
        this.id = id;
        this.name = name;
    }

    public void setId(int id){
        this.id = id;
    }

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

    public int getId(){
        return this.id;
    }

    public String getName(){
        return this.name;
    }
}

请帮忙

Answer 1

嘿，在得到正确的响应后尝试添加这段代码

例如，我正在尝试硬编码值。将其替换为您的 json。

   final List<String> yourlist=new ArrayList<String>();
    yourlist.add("Item 1");
    yourlist.add("Item 2");
    yourlist.add("Item 3");
    yourlist.add("Item 4");
    yourlist.add("Item 5");  
final Spinner sp1= (Spinner) findViewById(R.id.spinner1);
final Spinner sp2= (Spinner) findViewById(R.id.spinner2);

ArrayAdapter<String> adp1=new ArrayAdapter<String>(this,
                    android.R.layout.simple_list_item_1,yourlist);
    adp1.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
    sp1.setAdapter(adp1);

希望这有帮助。:)