【问题标题】：How to connect Android with PHP and MySQL? [duplicate]如何将 Android 与 PHP 和 MySQL 连接起来？ [复制]
【发布时间】：2014-02-02 21:49:22
【问题描述】：

我正在尝试将 Android 系统与 PHP 和 MySQL 连接以创建一个简单的登录活动。我正在使用在 4.2 Android 版本上运行的 genymotion 模拟器。

我在我的代码中使用线程使其在后台运行，并使用 JSON 以流畅的方式取回数据。

但问题是系统崩溃并强制关闭。如果有人可以帮助我，我将不胜感激。

日志猫

02-02 21:29:46.260: E/AndroidRuntime(1363): FATAL EXCEPTION: main
02-02 21:29:46.260: E/AndroidRuntime(1363): android.os.NetworkOnMainThreadException
02-02 21:29:46.260: E/AndroidRuntime(1363):     at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1133)
02-02 21:29:46.260: E/AndroidRuntime(1363):     at libcore.io.BlockGuardOs.connect(BlockGuardOs.java:84)
02-02 21:29:46.260: E/AndroidRuntime(1363):     at libcore.io.IoBridge.connectErrno(IoBridge.java:127)
02-02 21:29:46.260: E/AndroidRuntime(1363):     at libcore.io.IoBridge.connect(IoBridge.java:112)
02-02 21:29:46.260: E/AndroidRuntime(1363):     at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:192)
02-02 21:29:46.260: E/AndroidRuntime(1363):     at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:459)
02-02 21:29:46.260: E/AndroidRuntime(1363):     at java.net.Socket.connect(Socket.java:842)
02-02 21:29:46.260: E/AndroidRuntime(1363):     at org.apache.http.conn.scheme.PlainSocketFactory.connectSocket(PlainSocketFactory.java:119)
02-02 21:29:46.260: E/AndroidRuntime(1363):     at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:144)
02-02 21:29:46.260: E/AndroidRuntime(1363):     at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164)
02-02 21:29:46.260: E/AndroidRuntime(1363):     at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119)
02-02 21:29:46.260: E/AndroidRuntime(1363):     at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:360)
02-02 21:29:46.260: E/AndroidRuntime(1363):     at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555)
02-02 21:29:46.260: E/AndroidRuntime(1363):     at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487)
02-02 21:29:46.260: E/AndroidRuntime(1363):     at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:465)
02-02 21:29:46.260: E/AndroidRuntime(1363):     at pack.coderzheaven.JSONParser.makeHttpRequest(JSONParser.java:65)
02-02 21:29:46.260: E/AndroidRuntime(1363):     at pack.coderzheaven.AndroidPHPConnectionDemo$CheckLogin$1.run(AndroidPHPConnectionDemo.java:118)
02-02 21:29:46.260: E/AndroidRuntime(1363):     at android.os.Handler.handleCallback(Handler.java:730)
02-02 21:29:46.260: E/AndroidRuntime(1363):     at android.os.Handler.dispatchMessage(Handler.java:92)
02-02 21:29:46.260: E/AndroidRuntime(1363):     at android.os.Looper.loop(Looper.java:137)
02-02 21:29:46.260: E/AndroidRuntime(1363):     at android.app.ActivityThread.main(ActivityThread.java:5103)
02-02 21:29:46.260: E/AndroidRuntime(1363):     at java.lang.reflect.Method.invokeNative(Native Method)
02-02 21:29:46.260: E/AndroidRuntime(1363):     at java.lang.reflect.Method.invoke(Method.java:525)
02-02 21:29:46.260: E/AndroidRuntime(1363):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
02-02 21:29:46.260: E/AndroidRuntime(1363):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
02-02 21:29:46.260: E/AndroidRuntime(1363):     at dalvik.system.NativeStart.main(Native Method)

JSONParser.java

package pack.coderzheaven;

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();

            }
            */
             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;

    }
}

AndroidPHPConnectionDemo

package pack.coderzheaven;

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

import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.message.BasicNameValuePair;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import android.app.Activity;
import android.app.ProgressDialog;
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.TextView;

public class AndroidPHPConnectionDemo extends Activity {
    Button b;
    EditText et, pass;
    String Username, Password;
    TextView tv;
    HttpPost httppost;
    StringBuffer buffer;
    HttpResponse response;
    HttpClient httpclient;
    List<NameValuePair> nameValuePairs;

    String pid;

    // Progress Dialog
    private ProgressDialog pDialog;

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


    private static final String url_check_login = "http://10.0.3.2/check.php";

    // JSON Node names
    private static final String TAG_SUCCESS = "success";
    private static final String TAG_PERSON = "person";
    private static final String TAG_PID = "pid";
    private static final String TAG_NAME = "username";
    private static final String TAG_pass = "password";

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

        b = (Button) findViewById(R.id.Button01);
        et = (EditText) findViewById(R.id.username);
        pass = (EditText) findViewById(R.id.password);
        tv = (TextView) findViewById(R.id.tv);

        b.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                // login();

                // Getting complete person details in background thread
                new CheckLogin().execute();

            }
        });
    }

    /**
     * Background Async Task to Get complete person details
     * */
    class CheckLogin extends AsyncTask<String, String, String> {

        /**
         * Before starting background thread Show Progress Dialog
         * */
        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            pDialog = new ProgressDialog(AndroidPHPConnectionDemo.this);
            pDialog.setMessage("Loading person details. Please wait...");
            pDialog.setIndeterminate(false);
            pDialog.setCancelable(true);
            pDialog.show();
        }

        /**
         * Getting person details in background thread
         * */

        @Override
        protected String doInBackground(String... arg0) {
            // TODO Auto-generated method stub
            // updating UI from Background Thread
            runOnUiThread(new Runnable() {
                public void run() {
                    // Check for success tag
                    int success;
                    try {
                        // Building Parameters
                        List<NameValuePair> params = new ArrayList<NameValuePair>();
                        params.add(new BasicNameValuePair("pid", pid));

                        // getting person details by making HTTP request
                        // Note that person details url will use GET request
                        JSONObject json = jsonParser.makeHttpRequest(
                                url_check_login, "GET", params);

                        // check your log for json response
                        Log.d("Single person Details", json.toString());

                        // json success tag
                        success = json.getInt(TAG_SUCCESS);
                        if (success == 1) {
                            // successfully received person details
                            JSONArray productObj = json
                                    .getJSONArray(TAG_PERSON); // JSON Array

                            // get first product object from JSON Array
                            JSONObject person = productObj.getJSONObject(0);

                            et.setText(person.getString(TAG_NAME));
                            pass.setText(person.getString(TAG_pass));

                            Log.e("success in login", "SUCCESS IN LOGIN");

                        }

                        else {
                            // product with pid not found
                        }
                    } 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 got all details
            pDialog.dismiss();
        }
    }

检查.php

<?php

require_once('db_config.php'); 


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


//if(isset($_GET['Username'])and isset($_POST['Password'])){

  if(isset($_GET['pid'])){
//   $username = $_POST['Username'];
//   $password = $_POST['Password'];

     $pid = $_GET['pid'];   

//   $query_search = "select username, password from members where username = '".$username."' AND password = '".$password. "'";

     $query_search = "select from members where pid = '".$pid."'";   

     $query_exec = mysql_query($query_search) or die(mysql_error());

   if (mysql_num_rows($query_exec) > 0) 
   {
        $result = mysql_fetch_array($query_exec);

        $person = array();
        $person['username']=$result[username];
        $person['password']=$result['password'];

   // success
        $response["success"] = 1;

   // user node
        $response["person"] = array();

        array_push($response["person"], $person);

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

    }
    else
    {
   // no user found
            $response["success"] = 0;
            $response["message"] = "No User 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);
}    
?>

【问题讨论】：

android.os.NetworkOnMainThreadExceptio 在您提出问题之前，您在 Google 上搜索此例外或在此处搜索时学到了什么？
不，先生，这是我第一次询问这个具体问题，请不要马上评判我
为什么您是第一次就意味着您不必在提问之前进行搜索？
伙计，在我搜索并尝试多次解决这个问题后，你怎么了也？我第一次在stackoverflow上问这个问题是什么意思
友情提示：我还将调查针对您的 PHP 代码的 sql 注入保护 - w3schools.com/sql/sql_injection.asp

标签： php android mysql json android-asynctask

【解决方案1】：

问题在于 AsyncTask 中的 runOnUiThread。您收到异常是因为您将 UI 线程占用了太长时间。使用 AsyncTask 是正确的做法，但您在其中调用 runOnUiThread，这没有意义，因为它不再是异步的。

从做背景（）。
保留要在屏幕上显示的值作为异步任务的成员或作为结果模板参数。
将 setText 调用放在 postExecute 中，因为它在 UI 上运行线程。

类似这样的：

/**
 * Background Async Task to Get complete person details
 * */
class CheckLogin extends AsyncTask<String, String, String> {

    JSONArray productObj;

    /**
     * Before starting background thread Show Progress Dialog
     * */
    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        pDialog = new ProgressDialog(AndroidPHPConnectionDemo.this);
        pDialog.setMessage("Loading person details. Please wait...");
        pDialog.setIndeterminate(false);
        pDialog.setCancelable(true);
        pDialog.show();
    }

    /**
     * Getting person details in background thread
     * */

    @Override
    protected String doInBackground(String... arg0) {
        // TODO Auto-generated method stub

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

                    // getting person details by making HTTP request
                    // Note that person details url will use GET request
                    JSONObject json = jsonParser.makeHttpRequest(
                            url_check_login, "GET", params);

                    // check your log for json response
                    Log.d("Single person Details", json.toString());

                    // json success tag
                    success = json.getInt(TAG_SUCCESS);
                    if (success == 1) {
                        // successfully received person details
                        productObj = json
                                .getJSONArray(TAG_PERSON); // JSON Array

                    }

                    else {
                        // product with pid not found
                    }
                } 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 got all details


        if ( productObj != null ) {
            // get first product object from JSON Array
            JSONObject person = productObj.getJSONObject(0);

            et.setText(person.getString(TAG_NAME));
            pass.setText(person.getString(TAG_pass));

            Log.e("success in login", "SUCCESS IN LOGIN");
        }

        pDialog.dismiss();
    }
}

【讨论】：