Question

我正在做一个从json文件读取的Asynctask函数。我希望在postExecute传递上像字符串联系人的“nombre，categoria，hora，lugar ......”到另一个我有的活动。如何在postExecute上获取联系人的值？有人可以帮帮我吗？这是我的代码

private class GetProgramaSC extends AsyncTask<Void, Void, Void> {


        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            // Showing progress dialog
            pDialog = new ProgressDialog(getActivity());
            if(idioma.equalsIgnoreCase("es")){  
                pDialog.setMessage("Por favor espere...");
            }
            else{
                pDialog.setMessage("Itxaron mesedez...");
            }
            pDialog.setCancelable(false);
            pDialog.show();

        }

        @Override
        protected Void doInBackground(Void... arg0) {

                try {

                    JSONObject jsonObj = new JSONObject(loadJSONFromAsset());

                    // Getting JSON Array node
                   eventos = jsonObj.getJSONArray("results");

                    // looping through All Contacts
                    for (int i = 0; i < eventos.length(); i++) {
                        JSONObject c = eventos.getJSONObject(i);

                        String categoria = c.getString(TAG_CATEGORIA);
                        String nombre = c.getString(TAG_NOMBRE);
                        String hora = c.getString(TAG_HORA);
                        String lugar = c.getString(TAG_LUGAR);
                        String fecha = c.getString(TAG_FECHA);
                        String coordenadas = c.getString(TAG_COORDENADAS);
                        String info = c.getString(TAG_INFO);
                        String imagen= c.getString(TAG_IMAGEN);

                        // tmp hashmap for single contact
                        HashMap<String, String> contact = new HashMap<String, String>();

                        // adding each child node to HashMap key => value
                        contact.put("categoria", categoria);
                        contact.put("nombre", nombre);
                        contact.put("hora", hora);
                        contact.put("nombre_lugar", lugar);
                        contact.put("fecha", fecha);
                        contact.put("coordenadas", coordenadas);
                        contact.put("info", info);
                        contact.put("imagen", imagen);


                        // adding contact to contact list
                        eventosList.add(contact);
                    }
                } catch (JSONException e) {
                    e.printStackTrace();
                }


            return null;


        }

        @Override
        protected void onPostExecute(Void result) {
            super.onPostExecute(result);
            // Dismiss the progress dialog
            if (pDialog.isShowing())
                pDialog.dismiss();




        }

    }

非常感谢

Answer 1

将AsyncTask签名更改为：

private class GetProgramaSC extends AsyncTask<Void, Void, List<String>>

然后doInBackground必须返回List。因此，在eventos结束时返回doInBackground，您将收到onPostExecute。

private class GetProgramaSC extends AsyncTask<Void, Void, List<String>> {

...

    @Override
    protected List<String> doInBackground(Void... arg0) {

          ...

        return eventos;


    }

    @Override
    protected void onPostExecute(List<String> result) {
        super.onPostExecute(result);
        // Dismiss the progress dialog
        if (pDialog.isShowing())
            pDialog.dismiss();

    }

}

Answer 2

这很简单将数据传递给postexecute 并根据您的需要处理数据

Dispatcher

稍后将hashmap添加到bundle以传递活动

尝试：在后执行

  private class GetProgramaSC extends AsyncTask<String, String, String> {


            @Override
            protected void onPreExecute() {
                super.onPreExecute();
                // Showing progress dialog
                pDialog = new ProgressDialog(getActivity());
                if(idioma.equalsIgnoreCase("es")){  
                    pDialog.setMessage("Por favor espere...");
                }
                else{
                    pDialog.setMessage("Itxaron mesedez...");
                }
                pDialog.setCancelable(false);
                pDialog.show();

            }

            @Override
            protected Void doInBackground(String... arg0) {



                return loadJSONFromAsset();


            }

            @Override
            protected void onPostExecute(String result) {
                super.onPostExecute(result);
                // Dismiss the progress dialog

      try {

                        JSONObject jsonObj = new JSONObject(result);

                        // Getting JSON Array node
                       eventos = jsonObj.getJSONArray("results");

                        // looping through All Contacts
                        for (int i = 0; i < eventos.length(); i++) {
                            JSONObject c = eventos.getJSONObject(i);

                            String categoria = c.getString(TAG_CATEGORIA);
                            String nombre = c.getString(TAG_NOMBRE);
                            String hora = c.getString(TAG_HORA);
                            String lugar = c.getString(TAG_LUGAR);
                            String fecha = c.getString(TAG_FECHA);
                            String coordenadas = c.getString(TAG_COORDENADAS);
                            String info = c.getString(TAG_INFO);
                            String imagen= c.getString(TAG_IMAGEN);

                            // tmp hashmap for single contact
                            HashMap<String, String> contact = new HashMap<String, String>();

                            // adding each child node to HashMap key => value
                            contact.put("categoria", categoria);
                            contact.put("nombre", nombre);
                            contact.put("hora", hora);
                            contact.put("nombre_lugar", lugar);
                            contact.put("fecha", fecha);
                            contact.put("coordenadas", coordenadas);
                            contact.put("info", info);
                            contact.put("imagen", imagen);


                            // adding contact to contact list
                            eventosList.add(contact);
                        }
                    } catch (JSONException e) {
                        e.printStackTrace();
                    }

 if (pDialog.isShowing())
                    pDialog.dismiss();




            }

        }

和另一个活动

Bundle extras = new Bundle();
extras.putSerializable("HashMap",hashMap);
intent.putExtras(extras);

Answer 3

传递大量的String数据无法借助于另一个活动的意图来完成，因此在解析JSON之后，您可以将它们存储在Application类中，该类可以在项目内的任何位置调用。

Answer 4

使用Object扩展您的类（无论您想要什么作为结果）以获得结果

public class GetProgramaSC extends AsyncTask<Void, Void, Object> {}

使用get（）方法调用asyncTask，但请记住它将在主线程上运行。

Object result = new GetProgramaSC().get();

希望它会对你有所帮助！

Answer 5

    @Override
        protected void onPostExecute(Void result) {
            super.onPostExecute(result);
            // Dismiss the progress dialog
            if (pDialog.isShowing())
                pDialog.dismiss();
            Intent i = new Intent(getActivity, NewActivity.class);
            i.putExtra("arraylist", eventolist);
            startActivity(i);
}

然后关于新活动：

ArrayList<HashMap<String, String>> arraylist = (ArrayList<HashMap<String,String>>) getIntent().getSerializableExtra("arraylist");

现在只需从新活动中的arraylist中提取hashmap及其值！例如： - arraylist.get（0）.get（＆＃34; nombre＆＃34;）;

获取后期执行的值

5 个答案: