Logout button, closing window and opening login/register window and tabs

Titanium.UI.setBackgroundColor('#fff');
 
    var tabGroup = Titanium.UI.createTabGroup({});
    var main = Titanium.UI.createWindow({}); 
    var mainTab = Titanium.UI.createTab();
    var userkey='BLAP';
 
    var login = Titanium.UI.createWindow({
        backgroundImage: 'images/login_background.png', 
        title:'Mingle Dating Application',
        url:'ui/loginWindow.js',
        barColor:'#373b3c',
        barImage:'images/bar/login.png'
        });
 
 
    //MAAK TITLE BAR TEXT TRANSPARANT
    var titleLabel = Titanium.UI.createLabel({
    color:'transparent',
    });
    login.setTitleControl(titleLabel)
 
    var loginTab = Titanium.UI.createTab({
        title:"Login",
        icon:'images/nav/group.png',
        window:login
 
    });
 
    var register = Titanium.UI.createWindow({
        backgroundImage: 'images/blank_background.png', 
        barImage: 'images/bar/register_step1.png',
        title:'Sign Up !',
        url:'ui/registerWindow_step1.js',
        barColor:'#373b3c',
        barImage: 'images/bar/register_step1.png'
    });
 
    var registerTab = Titanium.UI.createTab({
        title:'New Account',
        icon:'images/nav/lock.png',
        window:register
    });
 
 
 
 
 
    tabGroup.addTab(loginTab);
    tabGroup.addTab(registerTab);
    tabGroup.open();
 
    //NAVIGATIE + WINDOWS 
 
    //DATEFEED
    var dateFeedWindow = Titanium.UI.createWindow({
        backgroundImage: 'images/blank_background.png', 
        barImage: 'images/bar/datefeed.png',
        title:'DateFeed',
        url:'ui/dateFeedWindow.js',
        barColor:'#373b3c',
 
    });
 
    var dateFeedTab = Titanium.UI.createTab({
        title:'Datefeed',
        icon:'images/nav/radar.png',
        window:dateFeedWindow
    });
 
    //BROADCAST
    var broadcastWindow = Titanium.UI.createWindow({
        backgroundImage: 'images/blank_background.png', 
        barImage: 'images/bar/broadcast.png',
        title:'Broadcast',
        url:'ui/broadcastWindow.js',
        barColor:'#373b3c',
 
    });
 
    var broadcastTab = Titanium.UI.createTab({
        title:'Broadcast',
        icon:'images/nav/hoorn.png',
        window:broadcastWindow
    });
 
    //MESSAGES
    var messagesWindow = Titanium.UI.createWindow({
        backgroundImage: 'images/blank_background.png', 
        barImage: 'images/bar/messages.png',
        title:'Messages',
        url:'ui/messagesWindow.js',
        barColor:'#373b3c',
 
    });
 
    var messagesTab = Titanium.UI.createTab({
        title:'Messages',
        icon:'images/nav/Enveloppe.png',
        window:messagesWindow
    });
 
    //SETTINGS
    var settingsWindow = Titanium.UI.createWindow({
        backgroundImage: 'images/blank_background.png', 
        barImage: 'images/bar/settings.png',
        title:'Settings',
        url:'ui/settingsWindow.js',
        barColor:'#373b3c',
 
    });
 
    var settingsTab = Titanium.UI.createTab({
        title:'Settings',
        icon:'images/nav/sleutel.png',
        window:settingsWindow
    });
 
    Ti.App.addEventListener ('logout_done',function (){
    tabGroup.removeTab(mainTab);
    tabGroup.removeTab(dateFeedTab);
    tabGroup.removeTab(broadcastTab);
    tabGroup.removeTab(messagesTab);
    tabGroup.removeTab(settingsTab);
 
    tabGroup.addTab(loginTab);
    tabGroup.addTab(registerTab);
    });
 
 
    Ti.App.addEventListener('grantEntrance', function(event)
    {
        /*
        main.tabBarHidden   = true;
        main.title      = 'Welcome ' + event.name;
        main.url        = 'ui/main.js';
        main.name       = event.name;
        main.email      = event.email;
        mainTab.window      = main;
        */
 
        dateFeedWindow.userkey = event.userkey;
        broadcastWindow.userkey = event.userkey;
        messagesWindow.userkey = event.userkey;
        settingsWindow.userkey = event.userkey;
 
 
 
        tabGroup.removeTab(registerTab);
        tabGroup.removeTab(loginTab);
        tabGroup.addTab(dateFeedTab);
        tabGroup.addTab(broadcastTab);
        tabGroup.addTab(messagesTab);
        tabGroup.addTab(settingsTab);
    });
 
 
 
     var logoutbutton = Ti.UI.createButton({
                title: "Logout",
                style: Ti.UI.iPhone.SystemButtonStyle.DONE
     });
 
 
 
   logoutbutton.addEventListener('click',function()
    {
 
 
        tabGroup.removeTab(dateFeedTab);
        tabGroup.removeTab(broadcastTab);
        tabGroup.removeTab(messagesTab);
        tabGroup.removeTab(settingsTab);
 
 
        tabGroup.addTab(loginTab);
        tabGroup.addTab(registerTab);
 
 
    });
 
 
 
    settingsWindow.setRightNavButton(logoutbutton);

Hi tried making a logout function by adding and removing tabs, but all i get is a white window when i logout. How can u fix this problem?

Might want to think about just closing the tabgroub completely and recreate the login window