会话管理器使用共享Pref

Question

我正在使用共享首选项来存储用户数据，并且在我的开始屏幕中，我想检查用户名是否已经登录，当用户仍未注销时，它将重定向到UserView.java应用程序启动，否则它将转到LoginActivity.java

我使用这些教程作为参考： Android Hive Tutorial Shared Pref，和 Android example tutorial Shared Pref ..

但是当我退出我的活动而没有退出时，下次我打开我的应用程序时它的状态会被注销（就像会话已经结束，虽然我还没有从我的应用程序注销），

我应该怎么做才能解决这个问题，所以每当我退出我的应用程序（没有注销）时，我的数据仍然存在于共享的pref中，并且会重定向到UserView.java，我的代码是否犯了错误？< / p>

这些是我的代码：

userSessionManager.java

package com.thesis.teamizer;

import java.util.HashMap;

import android.content.Context;
import android.content.SharedPreferences;
import android.content.SharedPreferences.Editor;

public class userSessionManager {

// Shared Preferences Reference
SharedPreferences CurrentSession;

// Editor Reference for Editing Shared Preferences
Editor editor;

// Context Reference
Context _context;

// Shared pref mode
int PRIVATE_MODE = 0;

// Sharef Preferences Name
public static String PrefName = "MyUsername";

// All Shared Preferences Keys
private static final String IS_USER_LOGIN = "IsUserLoggedIn";

// User name (make variable public to access from outside)
public static final String KEY_USERNAME = "username";

// Constructor
public userSessionManager(Context context) {
    this._context = context;
    CurrentSession = _context.getSharedPreferences(PrefName, PRIVATE_MODE);
    editor = CurrentSession.edit();
}

public void createUserLogin(String username) {

    // User has already login
    editor.putBoolean(IS_USER_LOGIN, true);

    // Storing username in pref
    editor.putString(KEY_USERNAME, username);

    // Editor ready to execute the previous codes
    editor.commit();
}

public boolean checkLogin() {
    // Check login status. If the user is not logged in
    if (!this.isUserLoggedIn()) {
        return true;
    }
    return false;
}

// Read session using hashmap
public HashMap<String, String> getUserDetails() {

    // Use hashmap to store user credentials
    HashMap<String, String> user = new HashMap<String, String>();

    // user name
    user.put(KEY_USERNAME, CurrentSession.getString(KEY_USERNAME, null));

    // return user
    return user;
}

public void logOut() {
    // clearing all data from Shared pref
    editor.remove(KEY_USERNAME);
    editor.clear();
    editor.commit();
}

// Will check if the user is Login or not by getting the boolean of
// IS_USER_LOGIN from CurrentSession(pref)
private boolean isUserLoggedIn() {
    // TODO Auto-generated method stub
    return CurrentSession.getBoolean(IS_USER_LOGIN, false);
}
}

LoginActivity.java

package com.thesis.teamizer;

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.JSONException;
import org.json.JSONObject;

import android.app.Activity;
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.Button;
import android.widget.EditText;
import android.widget.Toast;

public class LoginActivity extends Activity implements View.OnClickListener     {

private EditText etUsername;
private EditText etPassword;
private Button bLogin, bRegis, bAdmin;
userSessionManager session;
String loginUrl;
JSONParser jsonParser = new JSONParser();
private static final String TAG_SUCCESS = "success";
private static final String TAG_MESSAGE = "message";
private ProgressDialog pDialog;
String Username;

@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);

    setContentView(R.layout.login_screen);

    Declaration();

    bLogin.setOnClickListener(this);
    bRegis.setOnClickListener(this);
    bAdmin.setOnClickListener(this);

    if (session.checkLogin()) {
        Intent intent = new Intent("com.thesis.teamizer.USERVIEW");
        finish();
        startActivity(intent);
    }
}

private void Declaration() {
    // TODO Auto-generated method stub
    etUsername = (EditText) findViewById(R.id.etLoginUsername);
    etPassword = (EditText) findViewById(R.id.etLoginPassword);
    bLogin = (Button) findViewById(R.id.bLogin);
    bRegis = (Button) findViewById(R.id.bRegister);
    bAdmin = (Button) findViewById(R.id.bAdminadmin);
    session = new userSessionManager(getApplicationContext());
    HashMap<String, String> user = session.getUserDetails();
    Username = user.get(userSessionManager.KEY_USERNAME);
    myIP ip = new myIP();
    String myIp = ip.getIp();
    String thisPhp = "doLogin.php";
    loginUrl = myIp + thisPhp;

}

@Override
public void onClick(View v) {
    // TODO Auto-generated method stub
    switch (v.getId()) {
    case R.id.bLogin:
        new AttemptLogin().execute();

        break;

    case R.id.bRegister:
        Intent i = new Intent("com.thesis.teamizer.REGISTRATIONACTIVITY");
        startActivity(i);

        break;

    }
class AttemptLogin extends AsyncTask<String, String, String> {

    /**
     * Before starting background thread Show Progress Dialog
     * */
    boolean failure = false;

    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        pDialog = new ProgressDialog(LoginActivity.this);
        pDialog.setMessage("Attempting login...");
        pDialog.setIndeterminate(false);
        pDialog.setCancelable(true);
        pDialog.show();
    }

    @Override
    protected String doInBackground(String... args) {
        // TODO Auto-generated method stub
        // Check for success tag
        int success;
        String username = etUsername.getText().toString();
        String password = etPassword.getText().toString();

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

            Log.d("request!", "starting");
            // getting product details by making HTTP request
            JSONObject json = jsonParser.makeHttpRequest(loginUrl, "POST",
                    params);

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

            // json success tag
            success = json.getInt(TAG_SUCCESS);
            if (success == 1) {
                Log.d("Login Successful!", json.toString());
                String currentLoginUsername = username;
                session.createUserLogin(currentLoginUsername);
                Intent intent = new Intent("com.thesis.teamizer.USERVIEW");
                finish();
                startActivity(intent);
                String sukses = "Sukses login";
                return sukses;
            } else if (success == 0) {
                return json.getString(TAG_MESSAGE);
            }
        } 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();
        Toast.makeText(getApplicationContext(), file_url,
                Toast.LENGTH_SHORT).show();

    }

}

}

UserView.java

package com.thesis.teamizer;

import java.util.HashMap;

import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

public class UserView extends Activity implements View.OnClickListener {

public Button createGr, viewGr, createAn, viewAn, notification, logout,
        calendar, createEvent, myEvent, createTask, myTask;
public String Username;
userSessionManager session;
Intent i;

@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
    setContentView(R.layout.user_view);
    sessionAndDeclaration();
    createGr.setOnClickListener(this);
    viewGr.setOnClickListener(this);
    createAn.setOnClickListener(this);
    viewAn.setOnClickListener(this);
    notification.setOnClickListener(this);
    logout.setOnClickListener(this);
    createEvent.setOnClickListener(this);
    calendar.setOnClickListener(this);
    myEvent.setOnClickListener(this);
    createTask.setOnClickListener(this);
    myTask.setOnClickListener(this);
}

private void sessionAndDeclaration() {
    // TODO Auto-generated method stub
    session = new userSessionManager(getApplicationContext());
    HashMap<String, String> user = session.getUserDetails();

    // get name
    Username = user.get(userSessionManager.KEY_USERNAME);
    TextView a = (TextView) findViewById(R.id.tvUserVUsername);
    a.setText(Username);
    createGr = (Button) findViewById(R.id.bCreateGroup);
    viewGr = (Button) findViewById(R.id.bViewMyGroup);
    createAn = (Button) findViewById(R.id.bCreateAnnouncement);
    viewAn = (Button) findViewById(R.id.bViewMyAnnouncement);
    notification = (Button) findViewById(R.id.bNotification);
    logout = (Button) findViewById(R.id.bDoLogout);
    calendar = (Button) findViewById(R.id.bGoToMyCalendar);
    createEvent = (Button) findViewById(R.id.bCreateEvent);
    myEvent = (Button) findViewById(R.id.bGoToMyEvent);
    createTask = (Button) findViewById(R.id.bGoToCreateTask);
    myTask = (Button) findViewById(R.id.bGoToMyTask);
}

@Override
public void onClick(View v) {
    // TODO Auto-generated method stub
    switch (v.getId()) {

    case R.id.bCreateGroup:
        i = new Intent("com.thesis.teamizer.CREATEGROUPACTIVITY");
        startActivity(i);
        break;

    case R.id.bViewMyGroup:
        i = new Intent("com.thesis.teamizer.MYGROUPACTIVITY");
        startActivity(i);

        break;

    case R.id.bCreateAnnouncement:
        i = new Intent("com.thesis.teamizer.CREATEANNOUNCEMENTACTIVITY");
        startActivity(i);

        break;

    case R.id.bViewMyAnnouncement:
        i = new Intent("com.thesis.teamizer.VIEWALLANNOUNCEMENT");
        startActivity(i);
        break;

    case R.id.bNotification:
        i = new Intent("com.thesis.teamizer.NOTIFICATION");
        startActivity(i);
        break;

    case R.id.bDoLogout:
        AlertDialog.Builder builder = new AlertDialog.Builder(this);
        builder.setMessage("Are you sure you want to Logout?")
                .setCancelable(false)
                .setPositiveButton("Yes",
                        new DialogInterface.OnClickListener() {
                            public void onClick(DialogInterface dialog,
                                    int id) {
                                finish();
                                session.logOut();
                                Intent i = new Intent(
                                        "com.thesis.teamizer.LOGINACTIVITY");

                                // Closing all the Activities
                                i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);

                                // Add new Flag to start new Activity
                                i.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);

                                // Staring Login Activity
                                startActivity(i);
                                finish();
                            }
                        })
                .setNegativeButton("No",
                        new DialogInterface.OnClickListener() {
                            public void onClick(DialogInterface dialog,
                                    int id) {
                                dialog.cancel();
                            }
                        });
        AlertDialog alert = builder.create();
        alert.show();

        break;

    case R.id.bGoToMyCalendar:
        i = new Intent("com.thesis.teamizer.VIEWCALENDAR");
        startActivity(i);
        break;

    case R.id.bCreateEvent:
        i = new Intent("com.thesis.teamizer.CREATEEVENT");
        startActivity(i);

        break;

    case R.id.bGoToMyEvent:
        i = new Intent("com.thesis.teamizer.MYEVENT");
        startActivity(i);
        break;

    case R.id.bGoToCreateTask:
        i= new Intent("com.thesis.teamizer.CREATETASK");
        startActivity(i);
        break;

    case R.id.bGoToMyTask:
        i = new Intent("com.thesis.teamizer.MYTASK");
        startActivity(i);
        break;

    }
}

}