MainWindow.xaml

<Window x:Class="PasswordHoarder.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:viewmodels="clr-namespace:PasswordHoarder.ViewModels"
        xmlns:local="clr-namespace:PasswordHoarder"
        xmlns:views="clr-namespace:PasswordHoarder.Views"
        mc:Ignorable="d"
        Title="Password Hoarder" Height="600" Width="750" MinWidth="600" MinHeight="600">
    <DockPanel>
        <Menu DockPanel.Dock="Top" ItemsSource="{Binding MenuItems}" Height="20">
            <Menu.ItemContainerStyle>
                <Style TargetType="{x:Type MenuItem}">
                    <Setter Property="Command" Value="{Binding Command}" />
                </Style>
            </Menu.ItemContainerStyle>
            <Menu.ItemTemplate>
                <HierarchicalDataTemplate DataType="{x:Type viewmodels:MenuItemViewModel}" ItemsSource="{Binding Path=SubItems}">
                    <TextBlock Text="{Binding Header}"/>
                </HierarchicalDataTemplate>
            </Menu.ItemTemplate>
        </Menu>
        <Grid>
            <ContentControl Content="{Binding CurrentViewModel}">
                <ContentControl.Resources>
                    <DataTemplate DataType="{x:Type viewmodels:LoginViewModel}">
                        <views:LoginView/>
                    </DataTemplate>
                    <DataTemplate DataType="{x:Type viewmodels:AddPasswordViewModel}">
                        <views:AddPasswordView/>
                    </DataTemplate>
                    <DataTemplate DataType="{x:Type viewmodels:EditPasswordViewModel}">
                        <views:EditPasswordView/>
                    </DataTemplate>
                    <DataTemplate DataType="{x:Type viewmodels:BrowserViewModel}">
                        <views:BrowserView/>
                    </DataTemplate>
                    <DataTemplate DataType="{x:Type viewmodels:GeneratePasswordViewModel}">
                        <views:GeneratePasswordView/>
                    </DataTemplate>
                    <DataTemplate DataType="{x:Type viewmodels:HelpViewModel}">
                        <views:HelpView/>
                    </DataTemplate>
                    <DataTemplate DataType="{x:Type viewmodels:AboutViewModel}">
                        <views:AboutView/>
                    </DataTemplate>
                </ContentControl.Resources>
            </ContentControl>
        </Grid>
    </DockPanel>
</Window>