started with implementation of start menu,

not yet fully working, buttons need to be binded

MultiTerm.Core/ViewModel/ShellViewModel.cs

@@ -73,7 +73,7 @@ public partial class ShellViewModel : ObservableObject, IRecipient<IUserInterfac
         this.messenger.Register(this);
 
         // TEMP Init
-        this.AppendTerminalWithSelectedViewType(ProtocolType.Serial);
+        //this.AppendTerminalWithSelectedViewType(ProtocolType.Serial);
     }
 
     /// <summary>

MultiTerm.Wpf/Helpers/InvertedExtension.cs

@@ -0,0 +1,25 @@
+using MultiTerm.Wpf.ValueConverters;
+using System;
+using System.Windows.Data;
+using System.Windows.Markup;
+
+namespace MultiTerm.Wpf.Helpers;
+
+/// <summary>
+/// Extension that uses an <see cref="InverterConverter"/>.
+/// Inspired by: https://stackoverflow.com/questions/58519440/is-there-some-way-to-invert-a-converter
+/// </summary>
+public class InvertedExtension : MarkupExtension
+{
+    public IValueConverter Converter { get; set; }
+
+    public InvertedExtension(IValueConverter converter)
+    {
+        Converter = new InverterConverter() { Converter = converter };
+    }
+
+    public override object ProvideValue(IServiceProvider serviceProvider)
+    {
+        return Converter;
+    }
+}

MultiTerm.Wpf/ValueConverters/InverterConverter.cs

@@ -0,0 +1,23 @@
+using System;
+using System.Globalization;
+using System.Windows.Data;
+
+namespace MultiTerm.Wpf.ValueConverters;
+
+/// <summary>
+/// Reverses <see cref="IValueConverter"/>s.
+/// </summary>
+public class InverterConverter : IValueConverter
+{
+    public IValueConverter? Converter { get; set; }
+
+    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
+    {
+        return Converter.ConvertBack(value, targetType, parameter, culture);
+    }
+
+    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
+    {
+        return Converter.Convert(value, targetType, parameter, culture);
+    }
+}

MultiTerm.Wpf/View/ShellView.xaml

@@ -18,7 +18,8 @@
              d:DesignHeight="600" d:DesignWidth="1200">
     <UserControl.Resources>
         <!-- Value Converters -->
-        <conv:EnumDescriptionToMenuItemConverter x:Key="EnumDescriptionConverter"/>
+        <conv:EnumDescriptionToMenuItemConverter x:Key="EnumDescriptionToMenuItemConverter"/>
+        <conv:EnumValueToEnumDescriptionConverter x:Key="EnumValToDescConv"/>
         <conv:MessageImportanceToBrushConverter x:Key="MsgImportanceBrushConverter"/>
         <conv:MessageImportanceToFontWeightConverter x:Key="MsgImportanceFontWeightConverter"/>
         <conv:ProtocolTypeToIconConverter x:Key="ProtocolTypeIconConverter"/>
@@ -66,11 +67,11 @@
             <MenuItem Header="_Settings">
                 <controls:SingleSelectSubMenu Title="Default Data Display Newline Separator" HorizontalContentAlignment="Left" VerticalContentAlignment="Top"
                           OptionsSource="{Binding Source={StaticResource NewlineSeparatorTypeValues}}"
-                          SelectedMenuItem="{Binding DefaultReceiveNewlineSeparator, Mode=TwoWay, Converter={StaticResource EnumDescriptionConverter}}">
+                          SelectedMenuItem="{Binding DefaultReceiveNewlineSeparator, Mode=TwoWay, Converter={StaticResource EnumDescriptionToMenuItemConverter}}">
                 </controls:SingleSelectSubMenu>
                 <controls:SingleSelectSubMenu Title="Default Newline Separator on Send"
                           OptionsSource="{Binding Source={StaticResource NewlineSeparatorTypeValues}}"
-                          SelectedMenuItem="{Binding DefaultSendNewlineSeparator, Mode=TwoWay, Converter={StaticResource EnumDescriptionConverter}}">
+                          SelectedMenuItem="{Binding DefaultSendNewlineSeparator, Mode=TwoWay, Converter={StaticResource EnumDescriptionToMenuItemConverter}}">
                 </controls:SingleSelectSubMenu>
             </MenuItem>
             <!--<MenuItem Header="_View"/>-->
@@ -121,7 +122,7 @@
                         <controls:SingleSelectSubMenu Title="View type"
                             OptionsSource="{Binding Source={StaticResource TerminalViewTypeValues}}"
                             SelectedMenuItem="{Binding Data.SelectedTerminalViewType, Mode=TwoWay, Source={StaticResource proxy},
-                                               Converter={StaticResource EnumDescriptionConverter}}">
+                                               Converter={StaticResource EnumDescriptionToMenuItemConverter}}">
                         </controls:SingleSelectSubMenu>
                         
                         <Separator/>
@@ -140,7 +141,8 @@
             <DockPanel Grid.Row="0" Grid.RowSpan="2" Grid.Column="0" Width="Auto">
                 <GroupBox Header="Send History" DockPanel.Dock="Top">
                     <!-- History -->
-                    <ListView x:Name="historyListView" Height="{Binding Path=ActualHeight, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type StackPanel}}}"
+                    <ListView x:Name="historyListView" 
+                              Height="{Binding Path=ActualHeight, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type StackPanel}}}"
                               ItemsSource="{Binding Path=SelectedTerminalViewModel.SentMessagesHistory}"
                               VerticalContentAlignment="Top" 
                               ScrollViewer.HorizontalScrollBarVisibility="Disabled"
@@ -188,7 +190,7 @@
             <GridSplitter Grid.Column="0" Grid.RowSpan="2" Width="2.5" Background="LightGray"/>
 
             <!-- Tab control -->
-            <custom_controls:ExtendedTabControl Grid.Row="1" Grid.Column="1"
+            <custom_controls:ExtendedTabControl Grid.Row="1" Grid.Column="1" Panel.ZIndex="0"
                 x:Name="terminalTabControl"
                 IsSynchronizedWithCurrentItem="True"
                 behaviours:TabContent.IsCached="True"
@@ -219,11 +221,11 @@
                             <Ellipse Width="16" Height="16" Margin="0 0 8 0" 
                                    Stroke="Black" StrokeThickness="0.7"
                                    Fill="{Binding Path=CommunicationProtocolConnectionState, Converter={StaticResource PrtclConnectionStateBrushConverter}}"
-                                   ToolTip="{Binding Path=CommunicationProtocolConnectionState, Converter={StaticResource EnumDescriptionConverter}}"
+                                   ToolTip="{Binding Path=CommunicationProtocolConnectionState, Converter={StaticResource EnumValToDescConv}}"
                                    ToolTipService.InitialShowDelay="200"/>
                             <Image Height="17" Stretch="Fill" Margin="0 0 8 0" 
                                    Source="{Binding Path=ProtocolType, Converter={StaticResource ProtocolTypeIconConverter}}"
-                                   ToolTip="{Binding Path=ProtocolType,Converter={StaticResource EnumDescriptionConverter}}"
+                                   ToolTip="{Binding Path=ProtocolType,Converter={StaticResource EnumValToDescConv}}"
                                    ToolTipService.InitialShowDelay="200"/>
                             <TextBlock Text="{Binding Title, Mode=OneWay}" 
                                    ToolTip="{Binding Path=CommunicationProtocolLongIdentifier}"
@@ -258,6 +260,85 @@
                     </EventTrigger>
                 </custom_controls:ExtendedTabControl.Triggers>
             </custom_controls:ExtendedTabControl>
+            
+            <!-- Start Menu -->
+            <Border Grid.Row="1" Grid.Column="1" Width="400" Height="300" 
+                    BorderThickness="1" BorderBrush="Black" CornerRadius="10" 
+                    Panel.ZIndex="1">
+                <Border.Style>
+                    <Style TargetType="{x:Type Border}">
+                        <Setter Property="Visibility" Value="Collapsed"/>
+                        <Style.Triggers>
+                            <!-- Visible only when no tabs are available (0 items, fallback 0, to hide it on error) -->
+                            <DataTrigger Binding="{Binding Path=TerminalViewModels.Count, FallbackValue=0, TargetNullValue=0}" Value="0">
+                                <Setter Property="Visibility" Value="Visible"/>
+                            </DataTrigger>
+                        </Style.Triggers>
+                    </Style>
+                </Border.Style>
+                <!-- Content -->
+                <DockPanel LastChildFill="False">
+                    <!-- Intro -->
+                    <StackPanel  DockPanel.Dock="Top" Margin="10"
+                                 Orientation="Vertical">
+                        <TextBlock Text="Start menu" 
+                                   FontSize="20" FontWeight="SemiBold"/>
+                        <TextBlock Text="Welcome to MultiTerm. To open a Terminal, please select View type and Protocol below."
+                                   TextWrapping="Wrap"/>
+                    </StackPanel>
+
+                    <!-- Left side-->
+                    <StackPanel Orientation="Vertical" DockPanel.Dock="Left" VerticalAlignment="Center" Margin="40 10">
+                        <Label Content="View type:"/>
+                        <!-- Terminal View Types as ListBox, styled as RadioButton -->
+                        <ListBox BorderBrush="Transparent"
+                             ItemsSource="{Binding Source={StaticResource TerminalViewTypeValues}, Converter={StaticResource EnumValToDescConv}}" 
+                             SelectedItem="{Binding SelectedTerminalViewType, Mode=TwoWay, Converter={StaticResource EnumValToDescConv}}">
+                            <ListBox.Resources>
+                                <Style TargetType="{x:Type ListBoxItem}">
+                                    <Setter Property="Template">
+                                        <Setter.Value>
+                                            <ControlTemplate>
+                                                <RadioButton
+                                                Content="{TemplateBinding ContentPresenter.Content}"
+                                                IsChecked="{Binding Path=IsSelected,
+                                                RelativeSource={RelativeSource TemplatedParent},
+                                                Mode=TwoWay}"/>
+                                            </ControlTemplate>
+                                        </Setter.Value>
+                                    </Setter>
+                                </Style>
+                            </ListBox.Resources>
+                        </ListBox>
+                    </StackPanel>
+
+                    <!-- Right side-->
+                    <StackPanel Orientation="Vertical" DockPanel.Dock="Right" VerticalAlignment="Center" Margin="40 10">
+                        <Label Content="Protocol type:"/>
+                        <!-- ListBox with Protocol types-->
+                        <ListBox BorderBrush="Transparent"
+                                 ItemsSource="{Binding Source={StaticResource ProtocolTypeValues}, Converter={StaticResource EnumValToDescConv}}"
+                                 x:Name="listBoxStartMenuProtocols">
+                            <ListBox.Resources>
+                                <Style TargetType="{x:Type ListBoxItem}">
+                                    <Setter Property="Template">
+                                        <Setter.Value>
+                                            <ControlTemplate>
+                                                <!-- Button Command binds with DataContext of parent ListBox, CommandParameter binds with the item -->
+                                                <Button Margin="0 2"
+                                                    Content="{TemplateBinding ContentPresenter.Content}">
+                                                    <!--Command="{Binding Path=DataContext.AppendTerminalWithSelectedViewTypeTestCommand, ElementName=listBoxStartMenuProtocols}"
+                                                    CommandParameter="{Binding Path=., Converter={helpers:Inverted {StaticResource EnumValToDescConv}}}">-->
+                                                </Button>
+                                            </ControlTemplate>
+                                        </Setter.Value>
+                                    </Setter>
+                                </Style>
+                            </ListBox.Resources>
+                        </ListBox>
+                    </StackPanel>
+                </DockPanel>
+            </Border>
         </Grid>
     </DockPanel>
 </UserControl>