Question

在我的Android应用程序中，我收到了JSONArray并且我正在解析它并将其存储在arraylist中并将其附加到listview但是我面临一个错误整个列表显示在一个列出项目。但是我收到了4件物品。这就是我所做的一切。

    AsyncHttpClient client = new AsyncHttpClient();
    RequestParams params = new RequestParams();
    params.put("topicsJSON",composeJSON());
          client.post("http://www.example.com/load_topics.php",params,newAsyncHttpResponseHandler()
    {

        public void onSuccess(String response)
        {


            Gson gson = new GsonBuilder().create();
            try 
            {

                JSONArray arr = new JSONArray(response);

                for (int i = 0; i < arr.length(); i++) 
                {
                    //JSONObject obj = (JSONObject) arr.get(i);

                    list.add(arr.get(i).toString());
                    load_data();


                }
            }
            catch (JSONException e) 
            {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }

                }

        @Override
        public void onFailure(int statusCode, Throwable error,String content)

        {

            if (statusCode == 404) 

            {
                Toast.makeText(getApplicationContext(), "Requested resource not found", Toast.LENGTH_LONG).show();
            } 

            else if (statusCode == 500) 

            {
                Toast.makeText(getApplicationContext(), "Something went wrong at server end", Toast.LENGTH_LONG).show();
            } 

            else 

            {
                Toast.makeText(getApplicationContext(), "Unexpected Error occcured! [Most common Error: Device might not be connected to Internet]",
                        Toast.LENGTH_LONG).show();
            }
        }

    });



}

private String composeJSON() {
    // TODO Auto-generated method stub
    ArrayList<HashMap<String, String>> check_in_List;
    check_in_List = new ArrayList<HashMap<String, String>>();
    HashMap<String, String> map = new HashMap<String, String>();

    map.put("subject_code",received_subject_code);


    check_in_List.add(map);
    Gson gson = new GsonBuilder().create();
    return gson.toJson(check_in_List);

}

public void load_data()
{
    ArrayAdapter<String> phy = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1,list);

    l1.setAdapter(phy);

    l1.setOnItemClickListener(new OnItemClickListener() { 
        public void onItemClick(AdapterView<?> parent, View view,
            int position, long id) {
            // When clicked, show a toast with the TextView text 

            String pos = (String) l1.getItemAtPosition(position);

    }); 

}

Answer 1

我面临一个错误，整个列表显示在一个列表项中。但是我收到4件物品

在load_data();内调用for-loop，用于从JSONArray

中ArrayList获取数据

将load_data();移到for-loop之外，以在ListView的单独行中显示每个项目

Answer 2

按照：

private List<String> list = new ArrayList<String>();

try{
    JSONArray arr = json.getJSONArray("JSONArray Name");
        for (int i = 0; i < arr.length(); i++) {
            JSONObject c = arr.getJSONObject(i);
            list.add(c.getString("Object Name"));
        }
}catch (JSONException e) {
    // TODO Auto-generated catch block
        e.printStackTrace();
}

load_data();

Answer 3

每次都不添加列表项，创建适配器，

用空列表设置适配器一次。

结束后解析Jsonarray并添加数据，adapter.notifyDataSetChanged（）;

Answer 4

替换它：

            for (int i = 0; i < arr.length(); i++) 
            {
                //JSONObject obj = (JSONObject) arr.get(i);

                list.add(arr.get(i).toString());
                load_data();


            }

经

    for (int i = 0; i < arr.length(); i++) 
   {
           //JSONObject obj = (JSONObject) arr.get(i);

           list.add(arr.get(i).toString());
    }
load_data();

解析JSONArray并在android中的ListView中显示数据

4 个答案: