<?php

/*
 * Following code will delete a product from table
 * A product is identified by product id (pid)
 */

// array for JSON response
$response = array();

// check for required fields
if (isset($_POST['id'])) {
    $id = $_POST['id'];

    // include db connect class
    require_once __DIR__ . '/config.inc.php';

    // connecting to db
    $db = new DB_CONNECT();

    // mysql update row with matched pid
    $result = mysql_query("DELETE FROM foodordered WHERE id = $id");

    // check if row deleted or not
    if (mysql_affected_rows() > 0) {
        // successfully updated
        $response["success"] = 1;
        $response["message"] = "Product successfully deleted";

        // echoing JSON response
        echo json_encode($response);
    } else {
        // no product found
        $response["success"] = 0;
        $response["message"] = "No product found";

        // echo no users JSON
        echo json_encode($response);
    }
} else {
    // required field is missing
    $response["success"] = 0;
    $response["message"] = "Required field(s) is missing";

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

package com.yiqiexample.cc;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;

import org.apache.http.NameValuePair;
import org.apache.http.message.BasicNameValuePair;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import android.annotation.SuppressLint;
import android.app.Activity;
import android.app.AlertDialog;
import android.app.ListActivity;
import android.app.ProgressDialog;
import android.content.DialogInterface;
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.AdapterView;
import android.widget.BaseAdapter;
import android.widget.Button;
import android.widget.CheckBox;
import android.widget.EditText;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.SimpleAdapter;
//import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;
import android.widget.AdapterView.OnItemClickListener;



public class Food extends ListActivity
    implements OnClickListener {
    // Progress Dialog
        private ProgressDialog pDialog;
         private ListAdapter adapter;

    //testing on Emulator:
     private static final String READ_COMMENTS_URL = "http://10.0.2.2/pbda2/foodordered.php";
     private static final String url_delete_product = "http://10.0.2.2/pbda2/delete_product.php";

    // my ip add 192.168.43.176
     //private CheckBox chkFood, chkDrinks, chkServices;
      //private Button btnDisplay, chkClear, deliever, chkClearFood, fooddeliever, drinksdeliever, servicesdeliever, chkClearDrinks, chkClearServices;
      //private TextView clearThis,orderdisplay, clearThisFood, foodorderdisplay, drinksorderdisplay, servicesorderdisplay, clearThisDrinks, clearThisServices;

      private static final String TAG_SUCCESS = "success";
      private static final String TAG_POSTS = "posts";
        private static final String TAG_SEATNUMBER = "seatnumber";
        private static final String TAG_FOODORDERED = "foodordered";
        //it's important to note that the message is both in the parent branch of
        //our JSON tree that displays a "Post Available" or a "No Post Available" message,
        //and there is also a message for each individual post, listed under the "posts"
        //category, that displays what the user typed as their message.

      //An array of all of our comments
        private JSONArray mComments = null;
        //manages all of our comments in a list.
        private ArrayList<HashMap<String, String>> mCommentList;



    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        this.setContentView(R.layout.food);



        View v = findViewById(R.id.backmain);
        //set event listener
            v.setOnClickListener(this);

            View z = findViewById(R.id.drinksbtn);
            //set event listener
                z.setOnClickListener(this);

                View x = findViewById(R.id.servicebtn);
                //set event listener
                    x.setOnClickListener(this);




    }

    @Override
    protected void onResume() {
        // TODO Auto-generated method stub
        super.onResume();
        //loading the comments via AsyncTask
        new LoadComments().execute();
    }


    /**
     * Retrieves recent post data from the server.
     */
    public void updateJSONdata() {

        // Instantiate the arraylist to contain all the JSON data.
        // we are going to use a bunch of key-value pairs, referring
        // to the json element name, and the content, for example,
        // message it the tag, and "I'm awesome" as the content..

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

        // Bro, it's time to power up the J parser
        JSONParser jParser = new JSONParser();
        // Feed the beast our comments url, and it spits us
        //back a JSON object.  Boo-yeah Jerome.
        JSONObject json = jParser.getJSONFromUrl(READ_COMMENTS_URL);

        //when parsing JSON stuff, we should probably
        //try to catch any exceptions:
        try {

            //I know I said we would check if "Posts were Avail." (success==1)
            //before we tried to read the individual posts, but I lied...
            //mComments will tell us how many "posts" or comments are
            //available
            mComments = json.getJSONArray(TAG_POSTS);

            // looping through all posts according to the json object returned
            for (int i = 0; i < mComments.length(); i++) {
                JSONObject c = mComments.getJSONObject(i);

                //gets the content of each tag
                String seatnumber = c.getString(TAG_SEATNUMBER);
                String foodordered = c.getString(TAG_FOODORDERED);



                // creating new HashMap
                HashMap<String, String> map = new HashMap<String, String>();

                map.put(TAG_SEATNUMBER, seatnumber);
                map.put(TAG_FOODORDERED, foodordered);


                // adding HashList to ArrayList
                mCommentList.add(map);

                //annndddd, our JSON data is up to date same with our array list
            }

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









    @Override
            public void onClick(View arg0) {
        if(arg0.getId() == R.id.backmain){
            //define a new Intent for the second Activity
            Intent intent = new Intent(this,MainActivity.class);

            //start the second Activity
            this.startActivity(intent);
            }
        if(arg0.getId() == R.id.drinksbtn){
            //define a new Intent for the second Activity
            Intent intent = new Intent(this,Drinks.class);

            //start the second Activity
            this.startActivity(intent);
            }
        if(arg0.getId() == R.id.servicebtn){
            //define a new Intent for the second Activity
            Intent intent = new Intent(this,Services.class);

            //start the second Activity
            this.startActivity(intent);
            }



    }

    /**
     * Inserts the parsed data into the listview.
     */
    private void updateList() {
        // For a ListActivity we need to set the List Adapter, and in order to do
        //that, we need to create a ListAdapter.  This SimpleAdapter,
        //will utilize our updated Hashmapped ArrayList,
        //use our single_post xml template for each item in our list,
        //and place the appropriate info from the list to the
        //correct GUI id.  Order is important here.

        //ListAdapter
        adapter = new SimpleAdapter(this, mCommentList,
                R.layout.single_comment,
                new String[] { TAG_SEATNUMBER, TAG_FOODORDERED
                //TAG_DRINKSORDERED, TAG_SERVICES
                }, new int[] { R.id.seatnumber, R.id.orders
                //R.id.drinkstv, R.id.servicestv,
        //adapter = new SimpleAdapter(this, mCommentList,
                //R.layout.single_comment, new String[] { TAG_SEATNUMBER, TAG_FOODORDERED
                //TAG_DRINKSORDERED, TAG_SERVICES
                    //   }, new int[] { R.id.seatnumber, R.id.orders
                //R.id.drinkstv, R.id.servicestv,


         });

        setListAdapter(adapter);
        ListView lv = getListView();
        lv.setOnItemClickListener(new OnItemClickListener() {

            @SuppressLint("NewApi")
            @Override
            public void onItemClick(AdapterView<?> arg0, View arg1,
                    final int arg2, long arg3) {
                // TODO Auto-generated method stub

                AlertDialog.Builder alt = new AlertDialog.Builder(
                        Food.this,
                        android.R.style.Theme_DeviceDefault_Dialog);
                alt.setMessage("Order delivered??");
                alt.setPositiveButton("Yes",
                        new DialogInterface.OnClickListener() {

                            @Override
                            public void onClick(DialogInterface dialog,
                                    int which) {
                                // TODO Auto-generated method stub
                                mCommentList.remove(arg2);

                                ((BaseAdapter) adapter).notifyDataSetChanged();


                                //new
                             new DeleteProduct().execute();

                         //end new

                            }
                        });

                alt.setNegativeButton("No",
                        new DialogInterface.OnClickListener() {

                            @Override
                            public void onClick(DialogInterface dialog,
                                    int which) {
                                // TODO Auto-generated method stub

                                dialog.dismiss();

                            }
                        });
                AlertDialog dialog = alt.create();
                dialog.show();

                return;
            }
        });
    }


        // I shouldn't have to comment on this one:
        //etListAdapter(adapter);

        // Optional: when the user clicks a list item we
        //could do something.  However, we will choose
        //to do nothing...
        //ListView lv = getListView();
        //lv.setOnItemClickListener(new OnItemClickListener() {

            //@Override
            //public void onItemClick(AdapterView<?> parent, View view,
                //  int position, long id) {

                // This method is triggered if an item is click within our
                // list. For our example we won't be using this, but
                // it is useful to know in real life applications.





            //}
        //});



   //   }




    public class LoadComments extends AsyncTask<Void, Void, Boolean> {

        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            pDialog = new ProgressDialog(Food.this);
            pDialog.setMessage("Loading orders...");
            pDialog.setIndeterminate(false);
            pDialog.setCancelable(true);
            pDialog.show();
        }
        @Override
        protected Boolean doInBackground(Void... arg0) {
            //we will develop this method in version 2
            updateJSONdata();
            return null;

        }


        @Override
        protected void onPostExecute(Boolean result) {
            super.onPostExecute(result);
            pDialog.dismiss();
          //we will develop this method in version 2
            updateList();
        }
    }



    //new

    /*****************************************************************
     * Background Async Task to Delete Product
     * */
    class DeleteProduct extends AsyncTask<String, String, String> {

        /**
         * Before starting background thread Show Progress Dialog
         * */
        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            pDialog = new ProgressDialog(Food.this);
            pDialog.setMessage("Deleting Product...");
            pDialog.setIndeterminate(false);
            pDialog.setCancelable(true);
            pDialog.show();
        }

        /**
         * Deleting product
         * */
        protected String doInBackground(String... args) {

            // Check for success tag
            int success;
            try {
                // Building Parameters
                //List<NameValuePair> params = new ArrayList<NameValuePair>();
                //params.add(new BasicNameValuePair("pid", pid));

                // getting product details by making HTTP request
                //JSONObject json = jsonParser.makeHttpRequest(
                  //      url_delete_product, "POST", params);

                JSONParser jParser = new JSONParser();
                // Feed the beast our comments url, and it spits us
                //back a JSON object.  Boo-yeah Jerome.
                JSONObject json = jParser.getJSONFromUrl(url_delete_product);

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

                // json success tag
                success = json.getInt(TAG_SUCCESS);
                if (success == 1) {
                    // product successfully deleted
                    // notify previous activity by sending code 100
                    Intent i = getIntent();
                    // send result code 100 to notify about product deletion
                    setResult(100, i);
                    finish();
                }
            } 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();

        }

    }





}

<?php

/*
Our "config.inc.php" file connects to database every time we include or require
it within a php script.  Since we want this script to add a new user to our db,
we will be talking with our database, and therefore,
let's require the connection to happen:
*/
require("config.inc.php");

//initial query
$query = "Select * FROM foodordered";

//execute query
try {
    $stmt   = $db->prepare($query);
    $result = $stmt->execute();
}
catch (PDOException $ex) {
    $response["success"] = 0;
    $response["message"] = "Database Error!";
    die(json_encode($response));
}

// Finally, we can retrieve all of the found rows into an array using fetchAll
$rows = $stmt->fetchAll();


if ($rows) {
    $response["success"] = 1;
    $response["message"] = "Post Available!";
    $response["posts"]   = array();

    foreach ($rows as $row) {
        $post             = array();
        $post["seatnumber"] = $row["seatnumber"];
        $post["foodordered"]    = $row["foodordered"];
        //$post["drinksordered"]    = $row["drinksordered"];
        //$post["services"]    = $row["services"];



        //update our repsonse JSON data
        array_push($response["posts"], $post);
    }

    // echoing JSON response
    echo json_encode($response);


} else {
    $response["success"] = 0;
    $response["message"] = "No Post Available!";
    die(json_encode($response));
}

?>

JSONObject json = jParser.getJSONFromUrl(url_delete_product);

JSONObject json = jParser.getJSONFromUrl(
            url_delete_product+"?id="+idOfYourFoodItem);

$id = $_GET['id'];