Question

我正在开发一个应用程序，因为我必须从服务器接收数据，我成功读取了数据。在这里我有问题我从AsyncTask写的服务器代码接收数据，并从AsyncTask发送数据到我的活动，这里我只发送三个中的一个数据，我的json对象有3个对象。我可以在AsyncTask中获得3个对象但是没有得到在活动

我的AsyncTask

 public class ReceivingLatLongAsync extends AsyncTask<Void, Void, Void> {

private ProgressDialog pDialog;

Context mContext;

JSONArray jsonArryDetails=null;

public static final String DETAILS = "locations";
public static final String LAT = "lat";
public static final String LNG = "lng";
public static final String ADDRESS = "address";
public static final String CTIME = "ctime";

private String lat1;
private String lng1;
private String address1;
private String time1;


public ReceivingLatLongAsync(Context context){

    this.mContext = context;

}
@Override
protected void onPreExecute() {
    // TODO Auto-generated method stub
    super.onPreExecute();
    pDialog = new ProgressDialog(mContext);
     pDialog.setMessage("Please wait...");
     pDialog.setCancelable(false);
     pDialog.show();

}

@Override
protected Void doInBackground(Void... params) {
    // TODO Auto-generated method stub

    ServiceHandler serviceHandler= new ServiceHandler();

    String jSonString = `serviceHandler.makeServiceCall
         (TrafficConstants.RECIEVE_LATLON_POL_URL, ServiceHandler.POST);`

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

    if(jSonString != null){

        try {
            JSONObject jsonObject = new JSONObject(jSonString);

            jsonArryDetails = jsonObject.getJSONArray(DETAILS);

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

                JSONObject mapDetails =        
                          jsonArryDetails.getJSONObject(0);

                lat1 = mapDetails.getString(LAT);
                lng1 = mapDetails.getString(LNG);
                address1 = mapDetails.getString(ADDRESS);
                time1 = mapDetails.getString(CTIME);


                Log.e("ADDRESS1", address1);
                Log.e("TIME2",time1);



            }

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

    return null;
}
@Override
protected void onPostExecute(Void result) {
    // TODO Auto-generated method stub
    super.onPostExecute(result);
    pDialog.dismiss();

    Intent intent = new Intent(mContext,GetLatLongForTPActivity.class);
    intent.putExtra("LAT", lat1);
    intent.putExtra("LNG", lng1);
    intent.putExtra("ADDRESS", address1);
    intent.putExtra("time",time1);

    mContext.startActivity(intent);
}

    }

我的活动

  public class GetLatLongForTPActivity extends FragmentActivity 
                                implements LocationListener{

  @Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_get_lat_long_for_tp);

    timeEdit = (EditText)findViewById(R.id.timeId);
    submitBtn = (Button)findViewById(R.id.subId);   

     Intent intent = getIntent();
     String anotherLAT=intent.getStringExtra("LAT");
     String anotherLNG=intent.getStringExtra("LNG");

     Log.e(" NEW LATLONG",anotherLAT);

  }

Answer 1

因为它是一个json数组，现在你只发送最后一个对象而不是entier数组

Answer 2

更改此

 JSONObject mapDetails =        
                      jsonArryDetails.getJSONObject(0);

到

 JSONObject mapDetails =        
                      jsonArryDetails.getJSONObject(i);

您必须添加类似

的内容

   ArrayList<HashMap<String, String>> mylist = new ArrayList<HashMap<String, String>>();

   for(int i = 0;i<jsonArryDetails.length();i++){
            HashMap<String, String> map = new HashMap<String, String>();
            JSONObject mapDetails =        
                      jsonArryDetails.getJSONObject(i);

            lat1 = mapDetails.getString(LAT);
            lng1 = mapDetails.getString(LNG);
            address1 = mapDetails.getString(ADDRESS);
            time1 = mapDetails.getString(CTIME);
            map.put(LAT, lat1);
            map.put(LNG, lg1);
            map.put(ADDRESS, address1 );
            map.put(CTIME, time1 );

            mylist.add(map);

        }

Answer 3

在for循环中更改索引：

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

            JSONObject mapDetails =jsonArryDetails.getJSONObject(i);
            //etc                                                ^ //change here

Answer 4

您需要创建一个存储您正在使用的四个字段的类（lat，long，address，time），使该对象具有可比性，您可以使用此示例：http://aryo.lecture.ub.ac.id/android-passing-arraylist-of-object-within-an-intent/; 之后，您可以使用以下方法将数组附加到intent：

intent.putParcelableArrayListExtra(String name, ArrayList<? extends Parcelable> value)

这将是处理此问题的正确方法，即使它比您原本希望的要复杂一点。

在Android中解析Json对象？

4 个答案: