public AccountViewModel(ServiceConfiguration serviceConfiguration)
        {
            this.serviceConfiguration = serviceConfiguration;
            this.microsoftAccount     = new MicrosoftAccount(serviceConfiguration);
            this.CheckInternetConnection();
            NetworkChange.NetworkAvailabilityChanged += this.NetworkChange_NetworkAvailabilityChanged;

            this.SignInCommand  = new DelegateCommand(this.SignIn);
            this.SignOutCommand = new DelegateCommand(this.SignOut);
            this.LibraryCommand = new DelegateCommand(() =>
            {
                if (this.IsSignedIn)
                {
                    Process.Start(string.Format(CultureInfo.InvariantCulture, "{0}/preview/users/{1}", this.serviceConfiguration.PhotosynthUrl, this.Username));
                }
            });
        }
        public AccountViewModel(ServiceConfiguration serviceConfiguration)
        {
            this.serviceConfiguration = serviceConfiguration;
            this.microsoftAccount = new MicrosoftAccount(serviceConfiguration);            
            this.CheckInternetConnection();
            NetworkChange.NetworkAvailabilityChanged += this.NetworkChange_NetworkAvailabilityChanged;

            this.SignInCommand = new DelegateCommand(this.SignIn);
            this.SignOutCommand = new DelegateCommand(this.SignOut);
            this.LibraryCommand = new DelegateCommand(() =>
            {
                if (this.IsSignedIn)
                {
                    Process.Start(string.Format(CultureInfo.InvariantCulture, "{0}/preview/users/{1}", this.serviceConfiguration.PhotosynthUrl, this.Username));
                }
            });
        }