SharedPreferences

SessionManagement.java

import java.util.HashMap;

import android.annotation.SuppressLint;

import android.content.Context;

import android.content.Intent;

import android.content.SharedPreferences;

import android.content.SharedPreferences.Editor;

public class SessionManagement {

       SharedPreferences pref;

       Editor editor;

       Context _context;

       int PRIVATE_MODE = 0;

       private static final String PREF_NAME = "SharedPreferences_Name";

       private static final String IS_LOGIN = "IsLoggedIn";

       public static final String KEY_UserName = "UserName";

       public static final String KEY_Password = "Password";

       @SuppressLint("CommitPrefEdits")

       public SessionManagement(Context context) {

             this._context = context;

             pref = _context.getSharedPreferences(PREF_NAME, PRIVATE_MODE);

             editor = pref.edit();

       }

       /**

        * Create login session

        * */

       public void createLoginSession(String UserName, String Password) {

             editor.putBoolean(IS_LOGIN, true);

             editor.putString(KEY_UserName, UserName);

             editor.putString(KEY_Password, Password);

             editor.commit();

       }

       public void checkLogin() {

             if (!this.isLoggedIn()) {

                    Intent i = new Intent(_context, MainActivity.class);

                    i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);

                    i.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);

                    _context.startActivity(i);

             }

       }

       public HashMap<String, String> getUserDetails() {

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

             user.put(KEY_UserName, pref.getString(KEY_UserName, null));

             user.put(KEY_Password, pref.getString(KEY_Password, null));

             return user;

       }

       public void logoutUser() {

             editor.clear();

             editor.commit();

             Intent intent;

             intent = new Intent(_context, MainActivity.class);

             intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);

             intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);

             _context.startActivity(intent);

       }

       public boolean isLoggedIn() {

             return pref.getBoolean(IS_LOGIN, false);

       }

}

MainActivity.java

import java.util.HashMap;

import android.app.Activity;

import android.os.Bundle;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.Button;

import android.widget.EditText;

import android.widget.TextView;

public class MainActivity extends Activity {

       private TextView txtMsg;

       private EditText edtName, edtPassword;

       private Button BtnLogin, BtnLogout;

       public SessionManagement session;

       @Override

       protected void onCreate(Bundle savedInstanceState) {

             super.onCreate(savedInstanceState);

             setContentView(R.layout.main);

             session = new SessionManagement(getApplicationContext());

             txtMsg = (TextView) findViewById(R.id.txtMsg);

             edtName = (EditText) findViewById(R.id.edtName);

             edtPassword = (EditText) findViewById(R.id.edtPassword);

             BtnLogin = (Button) findViewById(R.id.BtnLogin);

             BtnLogout = (Button) findViewById(R.id.BtnLogout);

             BtnLogin.setOnClickListener(new OnClickListener() {

                    @Override

                    public void onClick(View v) {

                           session.createLoginSession(edtName.getText().toString(),

                                        edtName.getText().toString());

                           BtnLogout.setVisibility(View.VISIBLE);

                           BtnLogin.setVisibility(View.GONE);

                           edtName.setVisibility(View.GONE);

                           edtPassword.setVisibility(View.GONE);

                           session.checkLogin();

                           // get user data from session

                           HashMap<String, String> user = session.getUserDetails();

                           txtMsg.setText(user.get(SessionManagement.KEY_UserName));

                    }

             });

             BtnLogout.setOnClickListener(new OnClickListener() {

                    @Override

                    public void onClick(View v) {

                           session.logoutUser();

                    }

             });

       }

}

main.xml

<?xml version="1.0" encoding="utf-8"?>

<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"

    android:layout_width="match_parent"

    android:layout_height="wrap_content" >

    <LinearLayout

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:orientation="vertical"

        android:padding="1.5dp" >

        <TextView

            android:id="@+id/txtMsg"

            android:layout_width="fill_parent"

            android:layout_height="wrap_content"

            android:gravity="center_horizontal"

            android:padding="3dp"

            android:text="@string/Hello"

            android:textAppearance="?android:attr/textAppearanceMedium" />

        <EditText

            android:id="@+id/edtName"

            android:layout_width="match_parent"

            android:layout_height="wrap_content"

            android:layout_margin="1.5dp"

            android:ems="10"

            android:hint="@string/Name" >

            <requestFocus />

        </EditText>

        <EditText

            android:id="@+id/edtPassword"

            android:layout_width="match_parent"

            android:layout_height="wrap_content"

            android:layout_margin="1.5dp"

            android:ems="10"

            android:hint="@string/Password"

            android:inputType="textPassword" />

        <Button

            android:id="@+id/BtnLogin"

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:layout_margin="1.5dp"

            android:text="@string/Login" />

        <Button

            android:id="@+id/BtnLogout"

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:layout_margin="1.5dp"

            android:text="@string/Logout"

            android:visibility="gone" />

    </LinearLayout>

</ScrollView>

strings.xml

<resources>

    <string name="app_name">SharedPreferences</string>

    <string name="Logout">Logout</string>

    <string name="Login">Login</string>

    <string name="Name">Name</string>

    <string name="Hello">Hello</string>

    <string name="Password">Password</string>

</resources>