Q:

Httppost returning html instead Json code

here i´m in my first post. 
I´m getting started to android. 
I trying to connect my app to a webservice throu a tutorial from mybringback, but i´m getting an error with my json return.  
09-12 15:54:06.717: E/JSON Parser fallha(8254): Error parsing data org.json. JSONException: End of input at character 0 of 

I already found the reason, it´s happen becouse It´s returning the HTML from my php page instead json.  When i tried set a fix string with my json it worked.  
When i try to get the json from the browser it works fine.  
I set a Log.d in the reader and i got this:
09-12 15:35:10.807: D/Acha Erro POR FAVOR(6691):        <h1>Login</h1> 
09-12 15:35:10.807: D/Acha Erro(6691):      <form action="login.php" method="post"> 
09-12 15:35:10.807: D/Acha Erro(6691):          Username:<br /> 
09-12 15:35:10.807: D/Acha Erro(6691):          <input type="text" name="username" placeholder="username" /> 
09-12 15:35:10.807: D/Acha Erro(6691):          <br /><br /> 
09-12 15:35:10.807: D/Acha Erro(6691):          Password:<br /> 
09-12 15:35:10.807: D/Acha Erro(6691):          <input type="password" name="password" placeholder="password" value="" /> 
09-12 15:35:10.807: D/Acha Erro(6691):          <br /><br /> 
09-12 15:35:10.807: D/Acha Erro(6691):          <input type="submit" value="Login" /> 
09-12 15:35:10.807: D/Acha Erro(6691):      </form> 
09-12 15:35:10.807: D/Acha Erro(6691):      <a href="register.php">Register</a>

I´ve spent about 3 days trying to find out a way to solve that. 
Following my two classes and php
package com.example.testemysql;

import java.util. ArrayList;
import java.util. List;
import java.util.logging. LogRecord;

import org.apache.http. NameValuePair;
import org.apache.http.message. BasicNameValuePair;
import org.json. JSONException;
import org.json. JSONObject;

import android.app. Activity;
import android.app. ProgressDialog;
import android.content. Intent;
import android.os. AsyncTask;
import android.os. Bundle;
import android.util. Log;
import android.view. View;
import android.view. View. OnClickListener;
import android.widget. Button;
import android.widget. EditText;
import android.widget. Toast;

public class MainActivity extends Activity implements OnClickListener{

    private EditText user, pass;
    private Button mSubmit, mRegister;

     // Progress Dialog
    private ProgressDialog pDialog;

    // JSON parser class
    JSONParser jsonParser = new JSONParser();

    //php login script location:

    //localhost :  
    //testing on your device
    //put your local ip instead,  on windows, run CMD > ipconfig
    //or in mac's terminal type ifconfig and look for the ip under en0 or en1
   // private static final String LOGIN_URL = "http://xxx.xxx.x.x:1234/webservice/login.php";

    //testing on Emulator:
    private static final String LOGIN_URL = "http://www.bazarsol.6te.net/ANDROID/login.php";

  //testing from a real server:
    //private static final String LOGIN_URL = "http://www.yourdomain.com/webservice/login.php";

    //JSON element ids from repsonse of php script:
    private static final String TAG_SUCCESS = "success";
    private static final String TAG_MESSAGE = "message";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        //setup input fields
        user = (EditText)findViewById(R.id.username);
        pass = (EditText)findViewById(R.id.password);

        //setup buttons
        mSubmit = (Button)findViewById(R.id.login);
        mRegister = (Button)findViewById(R.id.register);

        //register listeners
        mSubmit.setOnClickListener(this);
        mRegister.setOnClickListener(this);

    }

    @Override
    public void onClick(View v) {
        // TODO Auto-generated method stub
        switch (v.getId()) {
        case R.id.login:
            new AttemptLogin().execute();   
            break;
        case R.id.register:
                //Intent i = new Intent(this, Register.class);
                //startActivity(i);
            break;

        default:
            break;
        }
    }

    class AttemptLogin extends AsyncTask<String, String, String> {

         /**
         * Before starting background thread Show Progress Dialog
         * */
        boolean failure = false;

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

        @Override
        protected String doInBackground(String... args) {
            // TODO Auto-generated method stub
             // Check for success tag
            int success;
            String username = user.getText().toString();
            String password = pass.getText().toString();
            try {
                // Building Parameters
                List<NameValuePair> params = new ArrayList<NameValuePair>();
                params.add(new BasicNameValuePair("username", username));
                params.add(new BasicNameValuePair("password", password));

                Log.d("URL",LOGIN_URL);
               Log.d("PARAMETROS",""+ params);

                Log.d("request!", " starting");
                // getting product details by making HTTP request
                JSONObject json = jsonParser.makeHttpRequest(
                        LOGIN_URL, "POST", params);

                // check your log for json response
                Log.d("Login attempt", json.toString());

                // json success tag
                success = json.getInt(TAG_SUCCESS);
                if (success == 1) {
                    //Log.d("Login Successful!",  json.toString());
                    Log.d("Login Successful!", ""); 
                    //Intent i = new Intent(Login.this, ReadComments.class);
                    finish();
                    //startActivity(i);
                    return json.getString(TAG_MESSAGE);
                }else{
                    Log.d("Login Failure!",  json.getString(TAG_MESSAGE));
                    return json.getString(TAG_MESSAGE);

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

            return null;

        }
        /**
         * After completing background task Dismiss the progress dialog
         * **/
        protected void onPostExecute(String file_url) {
            // dismiss the dialog once product deleted
            pDialog.dismiss();
            if (file_url ! = null){
                Toast.makeText(MainActivity.this, file_url, Toast. LENGTH_LONG).show();
            }

        }

    }

}

JSONParser
package com.example.testemysql;

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 mehtod
    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();
                Log.d("Acha o erro POR FAVOR ajuda",""+ httpResponse);

            }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);
            BufferedReader reader = new BufferedReader(new InputStreamReader(is,"UTF-8"));
            Log.d("Acha Erro POR FAVOR",""+ reader.readLine());
            StringBuilder sb = new StringBuilder();
            String line = null;
            while ((line = reader.readLine()) ! = null) {
                sb.append(line + "\n");
            }
            is.close();
            json = sb.toString();
            Log.d("Acha Erro", json);
        } catch (Exception e) {
            Log.e("Buffer Error", "Error converting result " + e);
        }

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

        // return JSON String
        return jObj;

    }
}

PHP - UPDATED
<? php

//load and connect to MySQL database stuff
require("config.inc.php");

//gets user's info based off of a username. 
$query = " 
        SELECT 
            indice, 
            usuario, 
            senha
        FROM usuarios 
        WHERE 
            usuario = :username 
    ";

$query_params = array(
    ':username' => $_POST["username"]
);

try {   
    $stmt   = $db->prepare($query);
    $result = $stmt->execute($query_params);
    print_r($_REQUEST);
    print_r (var_dump($_POST));
    print_r(get_headers());

    }
catch (PDOException $ex) {
    // For testing, you could use a die and message.  
    //die("Failed to run query: " .  $ex->getMessage());

    //or just use this use this one to product JSON data:
    $response["success"] = 0;
    $response["message"] = "Database Error1.  Please Try Again!2";
    echo "Bruno 2";
    die(json_encode($response&$ex));

}

//This will be the variable to determine whether or not the user's information is correct. 
//we initialize it as false. 
$validated_info = false;

//fetching all the rows from the query
$row = $stmt->fetch();
if ($row) {
    //if we encrypted the password, we would unencrypt it here, but in our case we just
    //compare the two passwords
    if ($_POST["password"] === $row["senha"]) {
        $login_ok = true;
    }
}

// If the user logged in successfully, then we send them to the private members-only page 
// Otherwise, we display a login failed message and show the login form again 
if ($login_ok) {
    $response["success"] = 1;
    $response["message"] = "Login successful!"; 
    die(json_encode($response));
} else {
    $response["success"] = 0;
    $response["message"] = "Invalid Credentials!"; 
    die(json_encode($response));
}? >

RESULTS
09-16 16:58:00.687: D/Acha o erro POR FAVOR ajuda(29176):org.apache.http.message. BasicHttpResponse@42680990
09-16 16:58:00.687: D/Acha Erro POR FAVOR(29176): Array
09-16 16:58:00.687: D/Acha Erro(29176): (
09-16 16:58:00.687: D/Acha Erro(29176): )
09-16 16:58:00.687: D/Acha Erro(29176): array(0) {
09-16 16:58:00.687: D/Acha Erro(29176): }
09-16 16:58:00.687: D/Acha Erro(29176): {"success":0,"message":"Invalid Credentials!"} 

A:

After all, i got a solution, the problem wasnt the code it was the server (6te.net) settings.  I tried in a local xampp server and it worked fine. 
Thanks to every body, especialy to greenapps.