added MergedDictionaries in Generic.xaml to split custom controls in seperate xaml files,

implemented add button visually in ExtendedTabControl

MultiTerm.Wpf.CustomControl/ExtendedTabControl/ExtendedTabControl.xaml

@@ -4,7 +4,7 @@
 
     <SolidColorBrush x:Key="TabItem.Selected.Background" Color="#FFFFFF"/>
     <SolidColorBrush x:Key="TabItem.Selected.Border" Color="#ACACAC"/>
-    <Style x:Key="TabControlStyle1" TargetType="{x:Type local:ExtendedTabControl}">
+    <Style TargetType="{x:Type local:ExtendedTabControl}">
         <Setter Property="Padding" Value="2"/>
         <Setter Property="HorizontalContentAlignment" Value="Center"/>
         <Setter Property="VerticalContentAlignment" Value="Center"/>
@@ -24,7 +24,10 @@
                             <RowDefinition x:Name="RowDefinition0" Height="Auto"/>
                             <RowDefinition x:Name="RowDefinition1" Height="*"/>
                         </Grid.RowDefinitions>
-                        <TabPanel x:Name="headerPanel" Background="Transparent" Grid.Column="0" IsItemsHost="true" Margin="2,2,2,0" Grid.Row="0" KeyboardNavigation.TabIndex="1" Panel.ZIndex="1"/>
+                        <StackPanel Orientation="Horizontal" Grid.Row="0" Grid.Column="0">
+                            <TabPanel x:Name="headerPanel" Background="Transparent" IsItemsHost="true" Margin="2,2,2,0" KeyboardNavigation.TabIndex="1" Panel.ZIndex="1"/>
+                            <Button Margin="2,2,2,2" Height="{TemplateBinding Height}" Width="{TemplateBinding Height}">+</Button>
+                        </StackPanel>
                         <Border x:Name="contentPanel" Background="{TemplateBinding Background}" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Grid.Column="0" KeyboardNavigation.DirectionalNavigation="Contained" Grid.Row="1" KeyboardNavigation.TabIndex="2" KeyboardNavigation.TabNavigation="Local">
                             <ContentPresenter x:Name="PART_SelectedContentHost" ContentSource="SelectedContent" Margin="{TemplateBinding Padding}" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/>
                         </Border>

MultiTerm.Wpf.CustomControl/Themes/Generic.xaml

@@ -0,0 +1,12 @@
+<ResourceDictionary
+    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+    xmlns:local="clr-namespace:MultiTerm.Wpf.CustomControl">
+
+    <!-- below all xaml files for custom controls shall be added -->
+    <ResourceDictionary.MergedDictionaries>
+        <ResourceDictionary Source="/MultiTerm.Wpf.CustomControl;component/ExtendedTabControl/ExtendedTabControl.xaml"/>
+
+    </ResourceDictionary.MergedDictionaries>
+
+</ResourceDictionary>

MultiTerm.Wpf/MultiTerm.Wpf.csproj

@@ -15,6 +15,7 @@
   <ItemGroup>
     <ProjectReference Include="..\Common\Common.csproj" />
     <ProjectReference Include="..\MultiTerm.Core\MultiTerm.Core.csproj" />
+    <ProjectReference Include="..\MultiTerm.Wpf.CustomControl\MultiTerm.Wpf.CustomControl.csproj" />
   </ItemGroup>
 
 </Project>

MultiTerm.Wpf/View/ShellView.xaml

@@ -6,6 +6,7 @@
              xmlns:sys="clr-namespace:System;assembly=mscorlib" 
              xmlns:conv="clr-namespace:MultiTerm.Wpf.ValueConverters"
              xmlns:controls="clr-namespace:MultiTerm.Wpf.Controls"
+             xmlns:custom_controls="clr-namespace:MultiTerm.Wpf.CustomControl;assembly=MultiTerm.Wpf.CustomControl"
              xmlns:vm="clr-namespace:MultiTerm.Core.ViewModel;assembly=MultiTerm.Core"
              xmlns:v="clr-namespace:MultiTerm.Wpf.View"
              xmlns:core_common="clr-namespace:MultiTerm.Core.Common;assembly=MultiTerm.Core"
@@ -125,13 +126,13 @@
                 <RibbonSeparator/>
             </RibbonMenuButton>-->
         </StackPanel>
-        <TabControl DockPanel.Dock="Right"
+        <custom_controls:ExtendedTabControl DockPanel.Dock="Right"
             x:Name="terminalTabControl"
             ItemsSource="{Binding TerminalViewModels}"
             SelectedItem="{Binding SelectedTerminalViewModel}">
 
             <!-- Tab Template -->
-            <TabControl.ItemTemplate>
+            <custom_controls:ExtendedTabControl.ItemTemplate>
                 <DataTemplate>
                     <StackPanel Orientation="Horizontal">
                         <TextBlock Text="{Binding Title, Mode=OneWay}" />
@@ -146,14 +147,14 @@
                         </Button>
                     </StackPanel>
                 </DataTemplate>
-            </TabControl.ItemTemplate>
+            </custom_controls:ExtendedTabControl.ItemTemplate>
 
             <!-- Register additional Tab ViewModels here -->
-            <TabControl.Resources>
+            <custom_controls:ExtendedTabControl.Resources>
                 <DataTemplate DataType="{x:Type vm:SendReceiveViewModel}">
                     <v:SendReceiveView/>
                 </DataTemplate>
-            </TabControl.Resources>
-        </TabControl>
+            </custom_controls:ExtendedTabControl.Resources>
+        </custom_controls:ExtendedTabControl>
     </DockPanel>
 </UserControl>