Cant seem to send JSONObject from android to remot

Question

I have been searching for a way to send data to a php page on a remote server and cant seem to get it to work...I modified the code from a similar question on here but it doesnt work still..do I have to put the httppost in an asynctask or something? How would I do that? Code:

public class gameOver extends Activity {
//TextView hiscores;
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.gameover);

    final Button b = (Button) findViewById(R.id.button1);
    b.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            // Perform action on click

            Toast.makeText(gameOver.this, "button was pressed",
                    Toast.LENGTH_SHORT).show();
            try {
                JSONObject json = new JSONObject(); 
                json.put("timestamp", 1351181576.64078); 
                json.put("name", "engine_speed");
                json.put("value", 714.0);
                postData(json);

                JSONObject json2 = new JSONObject(); 
                json2.put("timestamp", 1351181576.7207818); 
                json2.put("name", "steering_wheel_angle");
                json2.put("value", 11.1633);
                postData(json2);
            } catch (JSONException e) {
                e.printStackTrace();
            }

        }
    });     
}

public void postData(JSONObject json) throws JSONException {
    HttpClient httpclient = new DefaultHttpClient();
String URL = "http://www.mysite.com/s.php";
    try { 
        HttpPost httppost = new HttpPost(URL);

        List<NameValuePair> nvp = new ArrayList<NameValuePair>(2);    
        nvp.add(new BasicNameValuePair("json", json.toString()));

        httppost.setEntity(new UrlEncodedFormEntity(nvp));
        HttpResponse response = httpclient.execute(httppost); 

        if(response != null) {
            InputStream is = response.getEntity().getContent();
            //input stream is response that can be shown back on android
            Toast.makeText(gameOver.this, (CharSequence) is,
                    Toast.LENGTH_SHORT).show();
        }else{       Toast.makeText(gameOver.this, "data Not sent",
                Toast.LENGTH_SHORT).show();}


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

}

logcat:

09-06 11:45:28.986: W/System.err(30433): android.os.NetworkOnMainThreadException
09-06 11:45:28.986: W/System.err(30433):    at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1133)
09-06 11:45:28.986: W/System.err(30433):    at java.net.InetAddress.lookupHostByName(InetAddress.java:385)
09-06 11:45:28.986: W/System.err(30433):    at java.net.InetAddress.getAllByNameImpl(InetAddress.java:236)
09-06 11:45:28.986: W/System.err(30433):    at java.net.InetAddress.getAllByName(InetAddress.java:214)
09-06 11:45:28.986: W/System.err(30433):    at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:137)
09-06 11:45:28.986: W/System.err(30433):    at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164)
09-06 11:45:28.986: W/System.err(30433):    at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119)
09-06 11:45:28.986: W/System.err(30433):    at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:360)
09-06 11:45:28.986: W/System.err(30433):    at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555)
09-06 11:45:28.986: W/System.err(30433):    at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487)
09-06 11:45:28.986: W/System.err(30433):    at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:465)
09-06 11:45:28.986: W/System.err(30433):    at com.example.testgallery.gameOver.postData(gameOver.java:90)
09-06 11:45:28.986: W/System.err(30433):    at com.example.testgallery.gameOver$1.onClick(gameOver.java:65)
09-06 11:45:28.986: W/System.err(30433):    at android.view.View.performClick(View.java:4240)
09-06 11:45:28.986: W/System.err(30433):    at android.view.View$PerformClick.run(View.java:17721)
09-06 11:45:28.986: W/System.err(30433):    at android.os.Handler.handleCallback(Handler.java:730)
09-06 11:45:28.986: W/System.err(30433):    at android.os.Handler.dispatchMessage(Handler.java:92)
09-06 11:45:28.986: W/System.err(30433):    at android.os.Looper.loop(Looper.java:137)
09-06 11:45:28.986: W/System.err(30433):    at android.app.ActivityThread.main(ActivityThread.java:5103)
09-06 11:45:28.986: W/System.err(30433):    at java.lang.reflect.Method.invokeNative(Native Method)
09-06 11:45:28.986: W/System.err(30433):    at java.lang.reflect.Method.invoke(Method.java:525)
09-06 11:45:28.986: W/System.err(30433):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
09-06 11:45:28.996: W/System.err(30433):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
09-06 11:45:28.996: W/System.err(30433):    at dalvik.system.NativeStart.main(Native Method)
09-06 11:45:28.996: W/System.err(30433): android.os.NetworkOnMainThreadException
09-06 11:45:28.996: W/System.err(30433):    at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1133)
09-06 11:45:28.996: W/System.err(30433):    at java.net.InetAddress.lookupHostByName(InetAddress.java:385)
09-06 11:45:28.996: W/System.err(30433):    at java.net.InetAddress.getAllByNameImpl(InetAddress.java:236)
09-06 11:45:28.996: W/System.err(30433):    at java.net.InetAddress.getAllByName(InetAddress.java:214)
09-06 11:45:28.996: W/System.err(30433):    at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:137)
09-06 11:45:28.996: W/System.err(30433):    at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164)
09-06 11:45:28.996: W/System.err(30433):    at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119)
09-06 11:45:28.996: W/System.err(30433):    at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:360)
09-06 11:45:28.996: W/System.err(30433):    at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555)
09-06 11:45:28.996: W/System.err(30433):    at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487)
09-06 11:45:28.996: W/System.err(30433):    at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:465)
09-06 11:45:28.996: W/System.err(30433):    at com.example.testgallery.gameOver.postData(gameOver.java:90)
09-06 11:45:28.996: W/System.err(30433):    at com.example.testgallery.gameOver$1.onClick(gameOver.java:71)
09-06 11:45:28.996: W/System.err(30433):    at android.view.View.performClick(View.java:4240)
09-06 11:45:28.996: W/System.err(30433):    at android.view.View$PerformClick.run(View.java:17721)
09-06 11:45:28.996: W/System.err(30433):    at android.os.Handler.handleCallback(Handler.java:730)
09-06 11:45:28.996: W/System.err(30433):    at android.os.Handler.dispatchMessage(Handler.java:92)
09-06 11:45:28.996: W/System.err(30433):    at android.os.Looper.loop(Looper.java:137)
09-06 11:45:28.996: W/System.err(30433):    at android.app.ActivityThread.main(ActivityThread.java:5103)
09-06 11:45:28.996: W/System.err(30433):    at java.lang.reflect.Method.invokeNative(Native Method)
09-06 11:45:28.996: W/System.err(30433):    at java.lang.reflect.Method.invoke(Method.java:525)
09-06 11:45:28.996: W/System.err(30433):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
09-06 11:45:28.996: W/System.err(30433):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
09-06 11:45:28.996: W/System.err(30433):    at dalvik.system.NativeStart.main(Native Method)

Answer 1

Yes, you should definitely use AsyncTask to do that! In your code, you can create a class that extends AsyncTask :

public class LoadData extends AsyncTask<String, Integer, JSONObject> {

In this class, you will override 2 methods : doInBackground, that will do basically the code you have in your onClick() method, and onPostExecute() that wil do some processing with the response of the server.

protected JSONObject doInBackground(String... urls) {
    // Build your json objects and create an HttpPost that will contact the url in urls[0]
    // then return a JSONObject containing the response
}

protected void onPostExecute(JSONObject result) {
    // parse the content of result to analyze the response of the server
}

Then in your onClick method, you can create an instance of this class and call execute on it, passing the url you want to access :

LoadData loadData = new LoadData(getApplicationContext());
loadData.execute(your_url);

EDIT

I remember writing similar code for another person some time ago, you can check this post for another example : getting value using JSON nullpointer

Answer 2

You should you use AsyncTask to make send the data. I do not know your php page however I will try to explain how to send data to a server from android using JSON (If you have any further problems refer to this tutorial http://www.androidhive.info/2012/05/how-to-connect-android-with-php-mysql/). You are sending three values to the server as a POST request. I think your php file should receive the three variables and insert them into a database and then send back data accordingly.

Your php file (I am assuming you want to insert these values into a database named Details having three columns timestamp,name,value and then tell the app user if the data has been inserted or not.)

insert.php

<?php

    //connect to your database

    //declare an array to encode your response
    $arr = array();

    if((isset($_POST["timestamp"]))&&(isset($_POST["name"]))&&(isset($_POST["value"])))
     {
       $time = $_POST["timestamp"];
       $name = $_POST["name"];
       $value = $_POST["value"];
       $query = "insert into Details(timestamp,name,value) values '$time','$name','$value'";
       $result = mysql_query($result);
         if ($result) {
      // successfully inserted into database
         $arr["success"] = 1;
         $arr["message"] = "Data successfully inserted.";

    // echoing JSON response
        echo json_encode($arr);
        } else {
        // failed to insert row
         $arr["success"] = 0;
         $arr["message"] = "An error occurred.";

        // echoing JSON response
        echo json_encode($arr);
       }
       } else {
       // required field is missing
       $arr["success"] = 0;
       $arr["message"] = "Required field(s) is missing";

      // echoing JSON response
      echo json_encode($arr);
      }
?> 

Your class gameOver must have a subclass whiich must extend AsyncTask and do the JSON insertion.

gameOver Activity

      public class gameOver extends Activity {
    //TextView hiscores;
   JSONParser jsonParser; 
   protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.gameover);

final Button b = (Button) findViewById(R.id.button1);
b.setOnClickListener(new View.OnClickListener() {
    @Override 
    public void onClick(View v) {
        // Perform action on click 

        Toast.makeText(gameOver.this, "button was pressed",
                Toast.LENGTH_SHORT).show();
        new Insert().execute();

    } 
});      
} 

class Insert extends AsyncTask<String, String, String>

{

@Override
    protected void onPreExecute() {
      super.onPreExecute();
      pDialog = new ProgressDialog(gameOver.this);
      pDialog.setMessage("Inserting Details..");
      pDialog.setIndeterminate(false);
      pDialog.setCancelable(true);
      pDialog.show();
  }

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

    jsonParser = new JSONParser();

    //Building Parameters
    List<NameValuePair> params = new ArrayList<NameValuePair>();
    params.add(new BasicNameValuePair("timestamp",1351181576.64078));
    params.add(new BasicNameValuePair("name","engine_speed"));
    params.add(new BasicNameValuePair("value", 714.0));

    //getting JSON Object
    JSONObject json = jsonParser.makeHttpRequest("<your-domain-name>/insert.php", "POST", params);

    //Log.d("JSON:",json.toString());

    try
    {
        success = json.getInt("success");

        if(success == 1){
            Log.d("Query","Data Successfully inserted");
        }else{
            Log.d("Query","Unsuccessful in data submition");
        }
    }catch(JSONException e){
        Log.d("JSON:","EXCEPTION");
    }

    return null;
}    

The JSONParser class mentioned above is

package <your-package-name>;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;
import java.util.List;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.entity.UrlEncodedFormEntity;

import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.client.utils.URLEncodedUtils;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONException;
import org.json.JSONObject;

import android.util.Log;

public class JSONParser {

static InputStream is = null;
static JSONObject jObj = null;
static String json = "";

// constructor
public JSONParser() {

}

// function get json from url
// by making HTTP POST or GET method
public JSONObject makeHttpRequest(String url, String method,
        List<NameValuePair> params) {

    // Making HTTP request
    try {

        // check for request method
        if(method == "POST"){
            // request method is POST
            // defaultHttpClient
            DefaultHttpClient httpClient = new DefaultHttpClient();
            HttpPost httpPost = new HttpPost(url);
            httpPost.setEntity(new UrlEncodedFormEntity(params));

            HttpResponse httpResponse = httpClient.execute(httpPost);
            HttpEntity httpEntity = httpResponse.getEntity();
            is = httpEntity.getContent();

        }else if(method == "GET"){
            // request method is GET
            DefaultHttpClient httpClient = new DefaultHttpClient();
            String paramString = URLEncodedUtils.format(params, "utf-8");
            url += "?" + paramString;
            HttpGet httpGet = new HttpGet(url);

            HttpResponse httpResponse = httpClient.execute(httpGet);
            HttpEntity 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, "iso-8859-1"), 8);
        StringBuilder sb = new StringBuilder();
        String line = null;
        while ((line = reader.readLine()) != null) {
            sb.append(line + "\n");
        }
        is.close();
        json = sb.toString();
    } catch (Exception e) {
        Log.e("Buffer Error", "Error converting result " + e.toString());
    }

    // try parse the string to a JSON object
    try {
        jObj = new JSONObject(json);
    } catch (JSONException e) {
        Log.e("JSON Parser", "Error parsing data " + e.toString());
    }

    // return JSON String
    return jObj;

}
}