Question

我的问题是我的JSON在toast中返回的内容。吐司是让我知道查询是成功的。问题是toast被触发，这意味着查询成功，但它不包含Success []以外的任何内容。成功的查询应该以成功[JSON RESULTS HERE]的形式返回。

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更新：我收到org.json.JSONException：当我运行logCat时，org.json.JSONObject.get（JSONObject.java:354）的联盟没有值。

可能会发生什么？有没有人有任何解决方案？

JSON

{"version":"1.0","leagues":{"league":[{"homeURL":"http://www.myfantasyleague.com/2013/home/18752","name":"Northern Wisconsin Premier  FFL","id":"18752"},{"homeURL":"http://www.myfantasyleague.com/2013/home/36678","name":"Central Wisconsin Fantasy Football League","id":"36678"},{"homeURL":"http://www.myfantasyleague.com/2013/home/37766","name":"On Wisconsin","id":"37766"},{"homeURL":"http://www.myfantasyleague.com/2013/home/49677","name":"Wisconsin's Premier Dynasty Football League","id":"49677"}]},"encoding":"ISO-8859-1"}

主要活动

public final static String BaseUrl="DUMMYURL";
 ArrayList<DEPT_HOLD> deptList=new ArrayList<DEPT_HOLD>();

 private class GetDeptAyncTask extends AsyncTask<Hashtable<String,String>,Void,String>{ 
  // Parse in background
  @Override
  protected String doInBackground(Hashtable<String,String>... params) {
  @SuppressWarnings("rawtypes")
  Hashtable ht=params[0];
  @SuppressWarnings("unchecked")
  String json=HelperHttp.getJSONResponseFromURL(BaseUrl+"ENDOFDUMMYURL", ht);
   if(json!=null) parseJsonString(deptList,json);
   else {
    return "Invalid Company Id";
   }
    return "SUCCESS";
 }
 // Parse JSON
 protected void parseJsonString(ArrayList<DEPT_HOLD> deptList,String json) {
  try {
   JSONObject top = new JSONObject(json);
   JSONObject leagues = (JSONObject) top.get("leagues");
   JSONArray array = (JSONArray) leagues.get("league");
    for(int i = 0; i < array.length(); i++) {
     JSONObject j = array.getJSONObject(i);
     DEPT_HOLD d = new DEPT_HOLD();
      d.two = j.optString("name","");
      d.one = j.optString("id","");
       deptList.add(d);
    }
  } catch (JSONException e) {
   e.printStackTrace();
  }
 } 
 // Execute post
 @Override
 protected void onPostExecute(String result) {
  if("SUCCESS".equals(result)) {
   Toast.makeText(LeaguesTemporary.this, "Success "+deptList.size, Toast.LENGTH_LONG).show();

   DeptArrayAdapter adapter=new DeptArrayAdapter(LeaguesTemporary.this,R.id.text1,deptList);
   ListView listv=(ListView)findViewById(R.id.lv);
   listv.setAdapter(adapter);
  }
  else{}
 }    
}

吐司

Toast.makeText(MainActivity.this, "Success "+deptList.size(), Toast.LENGTH_LONG).show();

DEPT_HOLD.java

public class DEPT_HOLD {

public String two;
public String one;

}

DeptArrayAdapter

public class DeptArrayAdapter extends ArrayAdapter<DEPT_HOLD>{

private Context context;
ArrayList<DEPT_HOLD> dataObject;
public DeptArrayAdapter(Context context, int textViewResourceId,
        ArrayList<DEPT_HOLD> dataObject) {
    super(context, textViewResourceId, dataObject);
    this.context=context;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
    View rowView=convertView;
    if(rowView==null){
    LayoutInflater inflater = (LayoutInflater) context
            .getSystemService(Context.LAYOUT_INFLATER_SERVICE);

    rowView = inflater.inflate(R.layout.row_layout, parent, false);

    }
    TextView textView  = (TextView) rowView.findViewById(R.id.text1);
    TextView textView1 = (TextView) rowView.findViewById(R.id.text2);
    textView.setText(""+getItem(position).one);
    textView1.setText(""+getItem(position).two);

    return rowView;
}

}

HelperHttp

public class HelperHttp {

public static HttpClient httpclient;

private static List<NameValuePair> buildNameValuePair(Hashtable<String, String> httpPost){
      if(httpPost==null) return null;

      List <NameValuePair> nvps = new ArrayList <NameValuePair>();
      Enumeration<String> keys=httpPost.keys();
      while(keys.hasMoreElements()){
             String key = (String)keys.nextElement();
             String value = (String)httpPost.get(key);
             BasicNameValuePair nv=new BasicNameValuePair(key,value);
             nvps.add(nv);
      }

      return nvps;
     }


private static String buildGetUrl(List<NameValuePair> params, String url){
      String paramString = URLEncodedUtils.format(params, "utf-8");
      if(!url.endsWith("?"))
             url += "?";

      url+=paramString;
      return url;
     }

public static DefaultHttpClient getThreadSafeClient() {
    if (httpclient != null)
        return (DefaultHttpClient) httpclient;
    HttpParams params = new BasicHttpParams();
    ConnManagerParams.setMaxTotalConnections(params, 100);
    HttpProtocolParams.setVersion(params, HttpVersion.HTTP_1_1);

    // Create and initialize scheme registry 
    SchemeRegistry schemeRegistry = new SchemeRegistry();
    schemeRegistry.register(
            new Scheme("http", PlainSocketFactory.getSocketFactory(), 80));


    ClientConnectionManager cm = new ThreadSafeClientConnManager(params, schemeRegistry);
    httpclient = new DefaultHttpClient(cm, params);        

    return (DefaultHttpClient) httpclient;
}



public static String getJSONResponseFromURL(String url, Hashtable<String, String> httpGetParams){
      String json_string="";
      List<NameValuePair> nvps=buildNameValuePair(httpGetParams);
      url=buildGetUrl(nvps,url);
      System.out.println("URL==>"+url);
      InputStream is = null;
      try{
           HttpGet httpget = new HttpGet(url);
           HttpResponse response = getThreadSafeClient().execute(httpget);

           HttpEntity entity = response.getEntity();
           is = entity.getContent();
        BufferedReader reader=new BufferedReader(new InputStreamReader(is),8192);
        String line=null;
        while((line=reader.readLine())!=null){
         json_string=json_string+line;
        }
        response.getEntity().consumeContent();
        System.out.println("Json Response==>"+json_string);
      }catch(Exception e){
           Log.e("log_tag", "Error in http connection"+e.toString());
           return null;
      }
      return json_string;
     }

}

Answer 1

您的字符串比较不正确。而不是

result=="SUCCESS"

使用

"SUCCESS".equals(result)

（或者甚至更好，返回一个布尔值）

Answer 2

除了比较问题（由@ njzk2确定）之外，我认为您忘记打印列表的大小。

变化：

Toast.makeText(MainActivity.this, "Success "+deptList, Toast.LENGTH_LONG).show();

对此：

Toast.makeText(MainActivity.this, "Success "+deptList.size(), Toast.LENGTH_LONG).show();

Answer 3

也许您使用==来测试字符串相等性，并且“SUCCESS”共享相同的常量字符串，因此您总是得到假的True结果。尝试result.equals（“SUCCESS”）并再次运行。

Answer 4

尝试如下： -

      try {

        JSONObject jObject = new JSONObject(jsonString);
        JSONObject jLeagues = jObject.getJSONObject("leagues");
        JSONArray jLeague = jLeagues.getJSONArray("league");

        deptList = new ArrayList<DEPT_HOLD>();

        for (int i = 0; i < jLeague.length(); i++) {

            JSONObject jl = jLeague.getJSONObject(i);

            deptList.add(new DEPT_HOLD(jl.getString("name")));
            deptList.add(new DEPT_HOLD(jl.getString("id")));
            deptList.add(new DEPT_HOLD(jl.getString("homeURL")));

        }

        StringBuilder totalDept = new StringBuilder();
        for (int i = 0; i < deptList.size(); i++) {
            DEPT_HOLD dept = deptList.get(i);
            String value = dept.getName();

            totalDept.append(value + ",  \n");

        }
        Toast.makeText(ExampleJSONActivity.this, "success " + totalDept,
                Toast.LENGTH_LONG).show();

    } catch (Exception e) {
        // TODO: handle exception
    }

DEPT_HOLD： -

public class DEPT_HOLD {
    private String name;

    public DEPT_HOLD(String name) {
        super();

        this.name = name;
    }

    public String getName() {
        return name;
    }

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

}

Android中的JSON返回问题

4 个答案: