RetroFE/Configuration/Configuration/MainWindow.xaml

<Window x:Class="Configuration.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:v="clr-namespace:Configuration.View"
        xmlns:vm="clr-namespace:Configuration.ViewModel"
        xmlns:c="clr-namespace:Configuration.Converter"
        Title="RetroFE Configuration" Height="550" Width="600"
        Closing="Window_Closing"
        >
    
    <Window.Resources>
        <vm:LauncherListVM x:Key="LauncherConfig"/>
        <vm:CollectionListVM x:Key="CollectionConfig"/>
        <vm:MainVM x:Key="MainConfig"/>
        <vm:ControllerVM x:Key="ControllerConfig"/>
        <c:NullToVisibilityConverter x:Key="NullVisibilityConverter"/>
    </Window.Resources>

    <TabControl Name="ConfigurationTabControl" SelectionChanged="TabControl_SelectionChanged" FocusableChanged="TabControl_FocusableChanged">
        <TabItem Header="General">
            <v:MainSettings 
                Data="{Binding Mode=TwoWay, Source={StaticResource MainConfig}, Path=.}"
                Launchers="{Binding LauncherCollection, Source={StaticResource LauncherConfig}}" 
                Collections="{Binding CollectionList, Source={StaticResource CollectionConfig}}" 
                />
        </TabItem>
        <TabItem Header="Controller">
            <v:ControlInput Data="{Binding Mode=TwoWay, Source={StaticResource ControllerConfig}, Path=.}" />
        </TabItem>

        <TabItem Header="Launchers">
     
        <Grid>
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="Auto" MinWidth="100" />
                <ColumnDefinition Width="*" />
            </Grid.ColumnDefinitions>
        
                <v:AddRemoveList Grid.Column="0" 
                                 SelectedItem="{Binding SelectedLauncher, Mode=TwoWay, Source={StaticResource LauncherConfig}}" 
                                 ListDisplayMemberPath="Name"
                                 ListItemsSource="{Binding LauncherCollection, Source={StaticResource LauncherConfig}}" 
                                 AddListItemCommand="{Binding AddListItemCommand, Source={StaticResource LauncherConfig}}" 
                                 RemoveListItemCommand="{Binding RemoveListItemCommand, Source={StaticResource LauncherConfig}}"/>
                <StackPanel Grid.Column="1" Orientation="Vertical" Visibility="{Binding SelectedLauncher, Mode=TwoWay, Source={StaticResource LauncherConfig}, Converter={StaticResource NullVisibilityConverter}}">
                    <v:Launcher Data="{Binding SelectedLauncher, Mode=TwoWay, Source={StaticResource LauncherConfig}}"/>
                </StackPanel>
        </Grid>
        </TabItem>
        <TabItem Header="Collections">
            <Grid>
                <Grid.ColumnDefinitions>
                    <ColumnDefinition Width="Auto" MinWidth="100" />
                    <ColumnDefinition Width="*" />
                </Grid.ColumnDefinitions>
                <v:AddRemoveList Grid.Column="0" 
                                     SelectedItem="{Binding SelectedCollection, Mode=TwoWay, Source={StaticResource CollectionConfig}}" 
                                     ListDisplayMemberPath="Name"
                                     ListItemsSource="{Binding CollectionList, Source={StaticResource CollectionConfig}}" 
                                     AddListItemCommand="{Binding AddListItemCommand, Source={StaticResource CollectionConfig}}" 
                                     RemoveListItemCommand="{Binding RemoveListItemCommand, Source={StaticResource CollectionConfig}}"/>
                <StackPanel Grid.Column="1" Orientation="Vertical" Visibility="{Binding SelectedCollection, Mode=TwoWay, Source={StaticResource CollectionConfig}, Converter={StaticResource NullVisibilityConverter}}">
                    <v:Collection 
                        Data="{Binding SelectedCollection, Mode=TwoWay, Source={StaticResource CollectionConfig}}"
                        Layouts="{Binding Mode=TwoWay, Source={StaticResource MainConfig}, Path=Layouts}"
                        Collections="{Binding CollectionList, Source={StaticResource CollectionConfig}}" 
                        LauncherCollection="{Binding LauncherCollection, Source={StaticResource LauncherConfig}, Mode=TwoWay}" />
                </StackPanel>
            </Grid>
        </TabItem>
    </TabControl>

    
</Window>