Question

如何根据用户登录从ListView中的mysql数据库获取数据。以下是我得到的Json：

{"android":[{"username":"lokesh","company":"ffff","client":"xyz","client_no":"5487968475","callback":"2016-12-29 11:30:00"},
    {"username":"Rahul","company":"yyyy","client":"Suresh","client_no":"5789486589","callback":"2016-12-16 15:14:00"},
    {"username":"Fayaz","company":"ddddd","client":"Haresh","client_no":"4444889955","callback":"2016-12-28 14:00:00"},
    {"username":"Rahul","company":"qqqqq","client":"gore","client_no":"4444889955","callback":"2016-12-28 14:00:00"}]}

在这里，我越过Json，这是数据库中存在的完整数据，我在listview中获得了所有4个条目，但我真正想要的是如果我使用Rahul的用户名登录app，那么我应该只能看到2条记录。如果我以Fayaz身份登录，那么我应该只能在listview中看到1条记录。任何人都可以帮助我..以下是我的代码：活动：

public class AboutUsActivity extends AppCompatActivity implements LoadJSONTask.Listener, AdapterView.OnItemClickListener {

private ListView mListView;


public static final String URL = "http://10.0.2.2/android/get.php";
private List<HashMap<String, String>> mAndroidMapList = new ArrayList<>();

private static final String KEY_COMPANY = "company";
private static final String KEY_CLIENT = "client";
private static final String KEY_CLIENT_NO = "client_no";
private static final String KEY_CALLBACK = "callback";

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

    mListView = (ListView) findViewById(R.id.list_view);
    mListView.setOnItemClickListener(this);
    new LoadJSONTask(this).execute(URL);
}

@Override
public void onLoaded(List<AndroidVersion> androidList) {

    for (AndroidVersion android : androidList) {

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

        map.put(KEY_COMPANY, android.getCompany());
        map.put(KEY_CLIENT, android.getClient());
        map.put(KEY_CLIENT_NO, android.getClient_no());
        map.put(KEY_CALLBACK, android.getCallback());

        mAndroidMapList.add(map);
    }

    loadListView();
}

@Override
public void onError() {

    Toast.makeText(this, "Error !", Toast.LENGTH_SHORT).show();
}

@Override
public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {

    Toast.makeText(this, mAndroidMapList.get(i).get(KEY_CLIENT_NO),Toast.LENGTH_LONG).show();
}

private void loadListView() {

    ListAdapter adapter = new SimpleAdapter(AboutUsActivity.this, mAndroidMapList, R.layout.list_item,
            new String[] { KEY_COMPANY, KEY_CLIENT, KEY_CLIENT_NO, KEY_CALLBACK },
            new int[] { R.id.company,R.id.client, R.id.client_no,R.id.callback });

    mListView.setAdapter(adapter);

}
}

LoadJSONTask类：

public class LoadJSONTask extends AsyncTask<String, Void, Response> {

public LoadJSONTask(Listener listener) {

    mListener = listener;
}

public interface Listener {

    void onLoaded(List<AndroidVersion> androidList);

    void onError();
}

private Listener mListener;

@Override
protected Response doInBackground(String... strings) {
    try {

        String stringResponse = loadJSON(strings[0]);
        Gson gson = new Gson();

        return gson.fromJson(stringResponse, Response.class);
    } catch (IOException e) {
        e.printStackTrace();
        return null;
    } catch (JsonSyntaxException e) {
        e.printStackTrace();
        return null;
    }
}

@Override
protected void onPostExecute(Response response) {

    if (response != null) {

        mListener.onLoaded(response.getAndroid());

    } else {

        mListener.onError();
    }
}

private String loadJSON(String jsonURL) throws IOException {

    URL url = new URL(jsonURL);
    HttpURLConnection conn = (HttpURLConnection) url.openConnection();
    conn.setReadTimeout(10000);
    conn.setConnectTimeout(15000);
    conn.setRequestMethod("GET");
    conn.setDoInput(true);
    conn.connect();

    BufferedReader in = new BufferedReader(new InputStreamReader(conn.getInputStream()));
    String line;
    StringBuilder response = new StringBuilder();

    while ((line = in.readLine()) != null) {

        response.append(line);
    }

    in.close();
    return response.toString();
}
}

PHP FIle：

<?php 
session_start();
$sql = "SELECT * FROM meetdetails";
require_once('dbConnect.php');
$r = mysqli_query($con,$sql);
$android = array();
while($row = mysqli_fetch_array($r)){
array_push($android,array(
    'username'=>$row['username'],
    'company'=>$row['company_name'],
    'client'=>$row['client_name'],
    'client_no'=>$row['client_no'],
    'callback'=>$row['callback']
));
}

echo json_encode(array('android'=>$android));
mysqli_close($con);
?>

Answer 1

您可以将用户名发送到您的服务器，在那里他们将为您提供用户特定的请求，但您也必须要求他们执行此类操作。或创建HasmMap＆gt;在hasmap中存储用户特定数据，其中hasmap的KEY应该是username或user_id，然后你可以使用get方法从hasmap获取特定的用户数据。

Answer 2

将SQL结果保存在常规var中，然后在创建ListView之前根据用户名过滤数据。对于每个登录的用户名，过滤器仅代表他的数据。

其他选项是过滤适配器内的dada，再次根据连接的用户名隐藏不相关的项目。

如何在ListView中获取数据取决于用户？

2 个答案: