php - 连接 Android 应用程序以将字符串从 mysql 获取到 ListView 时出错

Question

在从 mysql 数据库填充 android listview 时，我收到此错误。我已经从 android hive 重建了这个脚本。我在 stackoverflow 上发现了这个错误，但因为我有另一个脚本，所以解决方案对我不起作用。它不是重复的，因为我的错误与 android 相关，而且我认为该错误不是我的问题。我收到此错误:

Deprecated: mysql_connect(): The mysql extension is deprecated and will be removed in the future: use mysqli or PDO instead in /android_connect/db_connect.php on line 28

get_all_products.php:

<?php

/*
 * Following code will list all the products
 */

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


// include db connect class
require_once __DIR__ . '/db_connect.php';

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

// get all products from products table
$result = mysql_query("SELECT *FROM products") or die(mysql_error());

// check for empty result
if (mysql_num_rows($result) > 0) {
    // looping through all results
    // products node
    $response["products"] = array();

    while ($row = mysql_fetch_array($result)) {
        // temp user array
        $product = array();
        $product["pid"] = $row["pid"];
        $product["name"] = $row["name"];
        $product["info"] = $row["info"];
        $product["created_at"] = $row["created_at"];



        // push single product into final response array
        array_push($response["products"], $product);
    }
    // success
    $response["success"] = 1;

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

    // echo no users JSON
    echo json_encode($response);
}
?>

db_connect.php:

/**
 * A class file to connect to database
 */

class DB_CONNECT {

// constructor
function __construct() {
    // connecting to database
    $this->connect();
}

// destructor
function __destruct() {
    // closing db connection
    $this->close();
}

/**
 * Function to connect with database
 */
function connect() {
    // import database connection variables
    require_once __DIR__ . '/db_config.php';

    // Connecting to mysql database
    $con = mysql_connect(DB_SERVER, DB_USER, DB_PASSWORD) or die(mysql_error());

    // Selecing database
    $db = mysql_select_db(DB_DATABASE) or die(mysql_error()) or die(mysql_error());

    // returing connection cursor
    return $con;
}

/**
 * Function to close db connection
 */
function close() {
    // closing db connection
    mysql_close();
}

}

?>Vergadertafel.java:

package my.domain.app;

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

import org.apache.http.NameValuePair;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import android.app.ListActivity;
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.widget.Toast;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import android.widget.TextView;

public class Vergadertafel extends ListActivity {

    // Progress Dialog
    private ProgressDialog pDialog;
    // Creating JSON Parser object
    JSONParser jParser = new JSONParser();

    ArrayList<HashMap<String, String>> infoList;

    // url to get all info list
    private static String de_info = "http://127.0.0.1/android_connect/get_all_products.php";

    // JSON Node names
    private static final String TAG_SUCCESS = "success";
    private static final String TAG_PRODUCTS = "products";
    private static final String TAG_NAME = "name";
    private static final String TAG_PID = "pid";
    private static final String TAG_INFO = "info";

    // info JSONArray
    JSONArray info = null;

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

        // Hashmap for ListView
        infoList = new ArrayList<HashMap<String, String>>();

        // Loading info in Background Thread
        new LoadAllInfo().execute();

        // Get listview
        ListView lv = getListView();

        // on seleting single info
        // launching Edit Info Screen
        lv.setOnItemClickListener(new OnItemClickListener() {

            @Override
            public void onItemClick(AdapterView<?> parent, View view,
                                    int position, long id) {
                // getting values from selected ListItem
                String pid = ((TextView) view.findViewById(R.id.pid)).getText()
                        .toString();

                // Starting new intent
                Intent in = new Intent(getApplicationContext(),
                        Info.class);
                // sending pid to next activity
                in.putExtra(TAG_PID, pid);

                // starting new activity and expecting some response back
                startActivityForResult(in, 100);
            }
        });

    }


    /**
     * Background Async Task to Load all info by making HTTP Request
     * */
    class LoadAllInfo extends AsyncTask<String, String, String> {

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

        /**
         * getting All info from url
         a* */
        protected String doInBackground(String... args) {
            // Building Parameters
            List<NameValuePair> params = new ArrayList<NameValuePair>();
            // getting JSON string from URL
            JSONObject json = jParser.makeHttpRequest(de_info, "GET", params);

            // Check your log cat for JSON reponse
            Log.d("All Info: ", json.toString());

            try {
                // Checking for SUCCESS TAG
                int success = json.getInt(TAG_SUCCESS);
        if (success== 0) {
            runOnUiThread(new Runnable() {
                public void run() {
                    Toast.makeText(getApplicationContext(), "Ik kan momenteel niet met de database communiceren, controleer uw internet verbinding en probeer het later nog eens.",
                            Toast.LENGTH_LONG).show();
                }
            });
        } else if (success == 1) {
                // info found
                // Getting Array of Info
                info = json.getJSONArray(TAG_PRODUCTS);

                // looping through All Info
                for (int i = 0; i < info.length(); i++) {
                    JSONObject c = info.getJSONObject(i);

                    // Storing each json item in variable
                    String id = c.getString(TAG_PID);
                    String name = c.getString(TAG_INFO);

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

                    // adding each child node to HashMap key => value
                    map.put(TAG_PID, id);
                    map.put(TAG_INFO, name);

                    // adding HashList to ArrayList
                    infoList.add(map);
                }

            } else {
            runOnUiThread(new Runnable() {
                public void run() {
                    Toast.makeText(getApplicationContext(), "Er is momenteel geen informatie beschikbaar, probeert u het later nog eens.",
                            Toast.LENGTH_LONG).show();
                }
            });
            }
        } catch (JSONException e) {
            Log.e("JSONException rule", " 153 Error:", e);
        }

        return null;
    }


        /**
         * After completing background task Dismiss the progress dialog
         * **/
        protected void onPostExecute(String file_url) {
            // dismiss the dialog after getting all info
            pDialog.dismiss();
            // updating UI from Background Thread
            runOnUiThread(new Runnable() {
                public void run() {
                    /**
                     * Updating parsed JSON data into ListView
                     * */
                    ListAdapter adapter = new SimpleAdapter(
                            Vergadertafel.this, infoList,
                            R.layout.list_item, new String[] { TAG_PID,
                            TAG_NAME},
                            new int[] { R.id.pid, R.id.name });
                    // updating listview
                    setListAdapter(adapter);
                }
            });

        }

    }
}

JSONParser.java: 打包 my.domain.app;

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("POST".equals(method)){
                // 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("GET".equals(method)){
                // 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) {
            Log.e("UnsupportedEncodingException", "error message:", e);
        } catch (ClientProtocolException e) {
            Log.e("ClientProtocolException", "error message", e);
        } catch (IOException e) {
            Log.e("IOException", "error message", e);
        }

        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);
        }

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

        // return JSON String
        return jObj;

    }
}

错误:

05-17 11:27:47.525     902-1128/my.domain.app E/JSON Parser﹕ Error parsing data
org.json.JSONException: Value <br of type java.lang.String cannot be converted to JSONObject
at org.json.JSON.typeMismatch(JSON.java:111)
at org.json.JSONObject.<init>(JSONObject.java:159)
at org.json.JSONObject.<init>(JSONObject.java:172)
at my.domain.app.JSONParser.makeHttpRequest(JSONParser.java:92)
at my.domain.app.Vergadertafel$LoadAllInfo.doInBackground(Vergadertafel.java:113)
at my.domain.app.Vergadertafel$LoadAllInfo.doInBackground(Vergadertafel.java:91)
at android.os.AsyncTask$2.call(AsyncTask.java:288)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
at java.lang.Thread.run(Thread.java:841)

Answer 1

这在您的 Android 代码中不是问题。问题的根源在于这一行:

$con = mysql_connect(DB_SERVER, DB_USER, DB_PASSWORD) or die(mysql_error());

您正在使用函数mysql_query来访问您的mysql数据库。然而，自 PHP 5.5 起，扩展 ext/mysql 中包含的带有前缀 mysql_ 的所有函数均已弃用。当您尝试使用它时，您会收到错误消息

Deprecated: mysql_connect(): The mysql extension is deprecated and will be removed in the future: use mysqli or PDO instead in /android_connect/db_connect.php on line 28

这基本上准确地告诉了你这一点。

由于发生此错误，die(mysql_error()) 结束脚本的执行并echo显示错误消息。您的 Android 应用程序依次尝试处理错误消息，意识到它不是有效的 JSON 字符串(实际上不是)并报告这一点。

为了防止这种情况，您可以抑制错误消息，但这根本不是一个好的做法。最好只使用 MySQLi或PDO_MySQL相反，扩展并未被弃用。