My app follow the below navigation

Home View -> Login View -> Campaign View

When a user tap on home view it redirects user to login view with below code

Code:
var loginstep = Ext.create('Myapp.view.Login');
Ext.Viewport.setActiveItem(loginstep);
When a user tap submit login form on Login view than it redirects user to campaign view with below code

Code:
success: function(response) {
                if(response.MESSAGE == 'success') {
                    Ext.Viewport.setMasked(false);
                    var firststep = Ext.create('Myapp.view.Campaignlist');
                    Ext.Viewport.setActiveItem(firststep);       
                }
}
Now i had a logout button on campaign view. I want when a user tap on it, user must go to home screen and agin the process should be continue.

For logout i had make a button with below code

Code:
{
                xtype: 'button',
                docked: 'bottom',
                ui: 'decline',
                style: 'border-radius:0',
                text: 'Logout',
                action: 'logoutuser'
}
Also make a function for logoutuser action in controller

Code:
logout: function() {
        Ext.Msg.confirm("Confirmation.....",
            "Are you sure you want to logout?",
            function ( answer ) {
                if(answer == 'yes') {
                    var loginstep1 = Ext.create('Myapp.view.Home');
                    Ext.Viewport.animateActiveItem(loginstep1, {type: 'slide', direction: 'right'});

                    //Ext.Viewport.add(loginstep1);      Also tried this code
                    //Ext.Viewport.setActiveItem(loginstep1);
                }
            });
    }
Using above codes user redirecting to home view but when i tried to again go to login view than the app break and nothing happened.