的logcat

Question

我有android应用程序，使用php使用android和mysql数据库之间的连接。获取mysql数据库后，我需要在android listview中显示结果。但问题是listview只显示表中的第一项，但是在php中获取表的结果返回表单显示了孔数据。

如何解决这个问题谁能帮助我？

的logcat

   04-1205: 40: 32.901: D/AllUsers: (1254): {
    "message": "DISPLAYED Success",
    "userlist": [
        {
            "id": "2",
            "user": "user2"
        },
        {
            "id": "3",
            "user": "michel"
        },
        {
            "id": "4",
            "user": "georges"
        },
        {
            "id": "5",
            "user": "testtest1"
        }
    ],
    "success": 1
}

列表视图只显示第一项：
- ＆＃34; id＆＃34;：＆＃34; 2＆＃34;， - ＆＃34;用户＆＃34;：＆＃34; user2＆＃34;

display_user.php

<?php

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

// 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 emp from emp table
$result = mysql_query("SELECT *FROM users") or die(mysql_error());

// check for empty result
if (mysql_num_rows($result) > 0) {


    // looping through all results
    // emp node
    $response["userlist"] = array();

    while ($row = mysql_fetch_array($result)) {
        $response["success"] = 1;
        // temp user array
            $userlist = array();
            $userlist["id"] = $row["id"];
            $userlist["user"] = $row["user"];



        // push single Employee into final response array
        array_push($response["userlist"], $userlist);
    }
    // success

    $response["message"] = "DISPLAYED Success";

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

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

JSONParser.java

package com.devleb.loginDemo;

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();

            }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();

            Log.i("TagCovertS", "["+json+"]");


        } 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;

    }
}

UserListActivity.java

package com.devleb.loginDemo;

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.os.AsyncTask;
import android.os.Bundle;
import android.app.Activity;
import android.app.ListActivity;
import android.content.Intent;
import android.util.Log;
import android.view.Menu;
import android.view.View;
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;
import android.widget.Toast;

public class UserListActivity extends ListActivity {

    JSONParser jsonParser = new JSONParser();

    ArrayList<HashMap<String, String>> usersList;

    private static String url_display_user = "http://10.0.3.2/android_connect/display_user.php";

    // JSON Node names
    private static final String TAG_SUCCESS = "success";
    private static final String TAG_MESSAGE = "message";

    private static final String TAG_ID = "id";


    private static final String TAG_USERS = "userlist";

    private static final String TAG_USER = "user";

    //private static final String TAG_NAME = "name";

    // employees JSONArray
    JSONArray users = null;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_user_list);

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

        new getUserList().execute();

        // getListView
        ListView lv = getListView();

        lv.setOnItemClickListener(new OnItemClickListener() {

            @Override
            public void onItemClick(AdapterView<?> arg0, View view, int arg2,
                    long arg3) {

            //  String id = ((TextView) view.findViewById(R.id.uid)).getText()
            //          .toString();

                // Intent in = new Intent(getBaseContext(), StatusList.class);
                // in.putExtra(TAG_ID, uid);

                // startActivity(in);
            }
        });
    }

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

        /**
         * Before starting background thread Show Progress Dialog
         * */
        @Override
        protected void onPreExecute() {
            super.onPreExecute();

            UserListActivity.this.setProgressBarIndeterminateVisibility(true);
        }

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

            // Building Parameters
            List<NameValuePair> parametres = new ArrayList<NameValuePair>();
            // getting JSON string from URL
            JSONObject json = jsonParser.makeHttpRequest(url_display_user,
                    "GET", parametres);

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

            try {
                // Checking for SUCCESS TAG
                int success = json.getInt(TAG_SUCCESS);

                if (success == 1) {
                    // products found
                    // Getting Array of Products
                    users = json.getJSONArray(TAG_USERS);

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

                        // Storing each json item in variable
                        String id = c.getString(TAG_ID);
                        String user = c.getString(TAG_USER);

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

                        // adding each child node to HashMap key => value
                        map.put(TAG_ID, id);
                        map.put(TAG_USER, user);

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

                        return json.getString(TAG_MESSAGE);
                    }
                } else {

                    return json.getString(TAG_MESSAGE);

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

            return null;
        }

        /**
         * After completing background task Dismiss the progress dialog
         * **/
        protected void onPostExecute(String result) {
            // dismiss the dialog after getting all products
            if (result != null) {

                UserListActivity.this
                        .setProgressBarIndeterminateVisibility(false);
                // updating UI from Background Thread
                runOnUiThread(new Runnable() {
                    public void run() {
                        /**
                         * Updating parsed JSON data into ListView
                         * */
                        ListAdapter adapter = new SimpleAdapter(
                                UserListActivity.this, usersList,
                                R.layout.list_item, new String[] { TAG_ID,
                                        TAG_USER }, new int[] { R.id.uid,
                                        R.id.name });
                        // updating listview
                        setListAdapter(adapter);
                    }
                });

                Toast.makeText(getBaseContext(), result, Toast.LENGTH_LONG)
                        .show();

            }
        }

    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.user_list, menu);
        return true;
    }

}

activity_user_list.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:background="@drawable/background_1">
<ListView
    android:id="@android:id/list"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />
</LinearLayout>

list_item.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical" >

    <TextView
        android:id="@+id/uid"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:visibility="gone" />

    <TextView
        android:id="@+id/name"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:paddingLeft="6dip"
        android:paddingTop="6dip"
        android:textColor="#FFFFFF"
        android:textSize="17dip"
        android:textStyle="bold" />

</LinearLayout>

Answer 1

你的问题是以下代码：

  for (int i = 0; i < users.length(); i++) {
          JSONObject c = users.getJSONObject(i);

          // Storing each json item in variable
          String id = c.getString(TAG_ID);
          String user = c.getString(TAG_USER);

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

          // adding each child node to HashMap key => value
          map.put(TAG_ID, id);
          map.put(TAG_USER, user);

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

          return json.getString(TAG_MESSAGE);
    }

你在json.getString(TAG_MESSAGE);语句中返回for所以for只是循环第一个位置，所以你得到你的json的第一行，从for语句中返回

您的代码必须是：

  for (int i = 0; i < users.length(); i++) {
          JSONObject c = users.getJSONObject(i);

          // Storing each json item in variable
          String id = c.getString(TAG_ID);
          String user = c.getString(TAG_USER);

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

          // adding each child node to HashMap key => value
          map.put(TAG_ID, id);
          map.put(TAG_USER, user);

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

    }
    return json.getString(TAG_MESSAGE);   <--- move this line after for statement

Answer 2

尝试这样，改变你的 onPostExecute 方法代码，如下所示。

ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, R.layout.list_item,
                usersList);
mListView.setCacheColorHint(Color.TRANSPARENT);
mListView.setAdapter(adapter);
adapter.notifyDataSetChanged();
adapter.setNotifyOnChange(false);
mListView.invalidateViews();

其中mListview是您的 ListView 对象，只需将您的 Listview 名称替换为其名称。

从mysql获取数据到android中的列表视图只显示表中的第一项如何修复？

的logcat

display_user.php

JSONParser.java

UserListActivity.java

activity_user_list.xml

list_item.xml

2 个答案: