public MainWindowViewModel(IViewModelFactory factory) { accountsWindowViewModel = factory.CreateAccountsWindowViewModel(); expensesWindowViewModel = factory.CreateExpensesWindowViewModel(); billsWindowViewModel = factory.CreateBillsWindowViewModel(); showAccountsCommand = new DelegateCommand(() => Current = accountsWindowViewModel); showExpensesCommand = new DelegateCommand(() => Current = expensesWindowViewModel); showBillsCommand = new DelegateCommand(() => Current = billsWindowViewModel); current = billsWindowViewModel; }