XAML Binding issue, Parent-Child, with two ListBoxes - wpf

Question

Pretty fresh in XAML, so need help. I am little lost with bindings. Because I think that is some issue over "Parent-Child" relationship, I make also short version of code. Maybe helps someone somewhere:)
PROBLEM: Until now I use only one ListBox in code, now I need two listbox.
Until now I bind so:
<DataTrigger Binding="{Binding IsSelected, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ListBoxItem}}}" Value="True">
How to bind selected with name? Because now I have two different ListBox. One have name "LstBox" another "SldBox".
My SHORT Code:
<Grid>
<Grid.Resources>
<DataTemplate>
<Canvas>
<Thumb>
<Thumb.Template>
<ControlTemplate>
<Canvas>
</Canvas>
<ControlTemplate.Triggers>
<DataTrigger Binding="{Binding IsSelected, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ListBoxItem}}}" Value="True">
<Setter TargetName="Ellipse" Property="Fill" Value="Red"/>
</DataTrigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Thumb.Template>
</Thumb>
</Canvas>
</DataTemplate>
</Grid.Resources>
<Grid>
<ListBox x:Name=LstBox>
<ListBox.Template>
<ControlTemplate>
<Border>
<Border.Background>
</Border.Background>
<ScrollViewer>
</ScrollViewer>
</Border>
</ControlTemplate>
</ListBox.Template>
<ListBox.ItemsSource>
<StaticResource ResourceKey="DiagramCol"/>
</ListBox.ItemsSource>
<ListBox.ItemsPanel>
<ItemsPanelTemplate>
<Canvas>
</Canvas>
</ItemsPanelTemplate>
</ListBox.ItemsPanel>
<ListBox.ItemContainerStyle>
<Style>
<Setter>
<Setter.Value>
<ControlTemplate>
<ControlTemplate.Triggers>
<Triggers>
</Triggers>
<DataTrigger>
</DataTrigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</ListBox.ItemContainerStyle>
<ListBox>
<ListBox x:Name=SldBox>
<ListBox.Template>
<ControlTemplate>
<Border>
<Border.Background>
</Border.Background>
<ScrollViewer>
</ScrollViewer>
</Border>
</ControlTemplate>
</ListBox.Template>
<ListBox.ItemsSource>
<StaticResource ResourceKey="DiagramCol"/>
</ListBox.ItemsSource>
<ListBox.ItemsPanel>
<ItemsPanelTemplate>
<Canvas>
</Canvas>
</ItemsPanelTemplate>
</ListBox.ItemsPanel>
<ListBox.ItemContainerStyle>
<Style>
<Setter>
<Setter.Value>
<ControlTemplate>
<ControlTemplate.Triggers>
<Triggers>
</Triggers>
<DataTrigger>
</DataTrigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</ListBox.ItemContainerStyle>
<ListBox>
</Grid>
My LONG Code:
<Grid>
<Grid.Resources>
<BooleanToVisibilityConverter x:Key="BoolToVisibilityConverter"/>
<CompositeCollection x:Key="DiagramCol">
<CollectionContainer Collection="{Binding DataContext.DiagramConnectors, Source={x:Reference diagramview}}"/>
<CollectionContainer Collection="{Binding DataContext.DiagramNodes, Source={x:Reference diagramview}}"/>
</CompositeCollection>
<CompositeCollection x:Key="SliderCol">
<CollectionContainer Collection="{Binding DataContext.SliderNodes, Source={x:Reference diagramview}}"/>
</CompositeCollection>
<!--NODES-->
<DataTemplate DataType="{x:Type local:DiagramNode}">
<Canvas Name="dragTarget">
<Thumb DragDelta="Thumb_Drag" DragStarted="Thumb_DragStarted" DragCompleted="Thumb_DragCompleted">
<Thumb.Template>
<ControlTemplate TargetType="Thumb">
<Canvas Margin="-10,-10,10,10">
<Ellipse Height="17" Width="17" Stroke="Black" StrokeThickness="1" Fill="Yellow"
x:Name="Ellipse"/>
<TextBlock Canvas.Top="-20" Canvas.Left="-40" Width="100"
TextAlignment="Center" Text="{Binding Name}" FontWeight="Bold"
IsHitTestVisible="False"
Visibility="{Binding DataContext.ShowNames,
RelativeSource={RelativeSource FindAncestor, AncestorType=Window},
Converter={StaticResource BoolToVisibilityConverter}}"/>
<TextBlock Canvas.Left="30" Canvas.Top="10"
Text="{Binding X, StringFormat='{}X = {0}'}"
IsHitTestVisible="False"
Visibility="Visible" x:Name="XText"/>
<TextBlock Canvas.Left="30" Canvas.Top="25"
Text="{Binding Xmeaning}"
IsHitTestVisible="False"
Visibility="Visible" x:Name="timeText"/>
<TextBlock Canvas.Left="30" Canvas.Top="40"
Text="{Binding Y, StringFormat='{}Y = {0}'}"
IsHitTestVisible="False"
Visibility="Visible" x:Name="YText"/>
</Canvas>
<ControlTemplate.Triggers>
<DataTrigger Binding="{Binding IsSelected, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ListBoxItem}}}" Value="True">
<Setter TargetName="Ellipse" Property="Fill" Value="Red"/>
</DataTrigger>
<Trigger Property="IsDragging" Value="True">
<Setter TargetName="Ellipse" Property="Fill" Value="Green"/>
</Trigger>
<DataTrigger Binding="{Binding DataContext.ShowAllCoordinates, RelativeSource={RelativeSource FindAncestor, AncestorType=Window}}" Value="True">
<Setter TargetName="XText" Property="Visibility" Value="Visible"/>
<Setter TargetName="YText" Property="Visibility" Value="Visible"/>
</DataTrigger>
<DataTrigger Binding="{Binding }" Value="True">
<Setter TargetName="Ellipse" Property="StrokeThickness" Value="2"/>
<Setter TargetName="Ellipse" Property="Stroke" Value="Red"/>
<Setter TargetName="Ellipse" Property="Fill" Value="White"/>
</DataTrigger>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding IsSelected, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ListBoxItem}}}" Value="True"/>
<Condition Binding="{Binding DataContext.ShowCurrentCoordinates, RelativeSource={RelativeSource FindAncestor, AncestorType=Window}}" Value="True"/>
</MultiDataTrigger.Conditions>
<Setter TargetName="XText" Property="Visibility" Value="Visible"/>
<Setter TargetName="YText" Property="Visibility" Value="Visible"/>
</MultiDataTrigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Thumb.Template>
</Thumb>
</Canvas>
</DataTemplate>
<!--Sliders-->
<DataTemplate DataType="{x:Type local:SliderNode}">
<Canvas Name="dragSlider">
<Thumb DragDelta="Thumb_Drag" DragStarted="Thumb_DragStarted" DragCompleted="Thumb_DragCompleted">
<Thumb.Template>
<ControlTemplate TargetType="Thumb">
<Canvas Margin="-10,-10,10,10">
<Rectangle Height="22" Width="5" Stroke="Black" StrokeThickness="1" Fill="Yellow" x:Name="Rectangle"/>
<!--<Ellipse Height="17" Width="17" Stroke="Black" StrokeThickness="1" Fill="Yellow"
x:Name="Ellipse"/>-->
<TextBlock Canvas.Top="-20" Canvas.Left="-40" Width="100"
TextAlignment="Center" Text="{Binding Name}" FontWeight="Bold"
IsHitTestVisible="False"
Visibility="{Binding DataContext.ShowNames,
RelativeSource={RelativeSource FindAncestor, AncestorType=Window},
Converter={StaticResource BoolToVisibilityConverter}}"/>
<TextBlock Canvas.Left="30" Canvas.Top="10"
Text="{Binding X, StringFormat='{}X = {0}'}"
IsHitTestVisible="False"
Visibility="Visible" x:Name="XText"/>
<TextBlock Canvas.Left="30" Canvas.Top="25"
Text="{Binding Xmeaning}"
IsHitTestVisible="False"
Visibility="Visible" x:Name="timeText"/>
<TextBlock Canvas.Left="30" Canvas.Top="40"
Text="{Binding Y, StringFormat='{}Y = {0}'}"
IsHitTestVisible="False"
Visibility="Visible" x:Name="YText"/>
</Canvas>
<ControlTemplate.Triggers>
<DataTrigger Binding="{Binding IsSelected, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ListBoxItem}}}" Value="True">
<Setter TargetName="Rectangle" Property="Fill" Value="Red"/>
</DataTrigger>
<Trigger Property="IsDragging" Value="True">
<Setter TargetName="Rectangle" Property="Fill" Value="Green"/>
</Trigger>
<DataTrigger Binding="{Binding DataContext.ShowAllCoordinates, RelativeSource={RelativeSource FindAncestor, AncestorType=Window}}" Value="True">
<Setter TargetName="XText" Property="Visibility" Value="Visible"/>
<Setter TargetName="YText" Property="Visibility" Value="Visible"/>
</DataTrigger>
<DataTrigger Binding="{Binding }" Value="True">
<Setter TargetName="Rectangle" Property="StrokeThickness" Value="2"/>
<Setter TargetName="Rectangle" Property="Stroke" Value="Red"/>
<Setter TargetName="Rectangle" Property="Fill" Value="White"/>
</DataTrigger>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding IsSelected, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ListBoxItem}}}" Value="True"/>
<Condition Binding="{Binding DataContext.ShowCurrentCoordinates, RelativeSource={RelativeSource FindAncestor, AncestorType=Window}}" Value="True"/>
</MultiDataTrigger.Conditions>
<Setter TargetName="XText" Property="Visibility" Value="Visible"/>
<Setter TargetName="YText" Property="Visibility" Value="Visible"/>
</MultiDataTrigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Thumb.Template>
</Thumb>
</Canvas>
</DataTemplate>
<!--CONNECTORS-->
<DataTemplate DataType="{x:Type local:DiagramConnector}">
<Line Stroke="OrangeRed" StrokeThickness="3"
X1="{Binding Start.X}" Y1="{Binding Start.Y}"
X2="{Binding End.X}" Y2="{Binding End.Y}" x:Name="Line"/>
<DataTemplate.Triggers>
<DataTrigger Binding="{Binding Start}" Value="{x:Null}">
<Setter TargetName="Line" Property="Visibility" Value="Collapsed"/>
</DataTrigger>
</DataTemplate.Triggers>
</DataTemplate>
</Grid.Resources>
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Name="column1" Width="*"/>
<ColumnDefinition Width="auto"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition Name="row1" Height="*"/>
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
</Grid.RowDefinitions>
<TextBlock Margin="2" x:Name="tbTitle" Grid.Column="1" Grid.Row="0" RenderTransformOrigin="0.5,0.5" FontSize="14" FontWeight="Bold" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" TextAlignment="Center" Text="{Binding GraphAddress}"/>
<TextBlock Margin="2" x:Name="tbXlabel" Grid.Column="1" Grid.Row="3" RenderTransformOrigin="0.5,0.5" TextAlignment="Center" Text="{Binding Xlabellabel}" />
<TextBlock Margin="2" x:Name="tbYlabelLeft" Grid.Column="0" Grid.Row="1" RenderTransformOrigin="0.5,0.5" TextAlignment="Center" Text="{Binding Ylabelleftlabel}">
<TextBlock.LayoutTransform>
<RotateTransform Angle="-90"/>
</TextBlock.LayoutTransform>
</TextBlock>
<TextBlock Margin="2" x:Name="tbYlabelRight" Grid.Column="2" Grid.Row="1" RenderTransformOrigin="0.5,0.5" TextAlignment="Center" Text="{Binding Ylabelrightlabel}">
<TextBlock.LayoutTransform>
<RotateTransform Angle="-90"/>
</TextBlock.LayoutTransform>
</TextBlock>
<ListBox SelectedItem="{Binding SelectedObject}"
PreviewMouseMove="ListBox_PreviewMouseMove"
PreviewMouseDown="ListBox_PreviewMouseDown"
PreviewMouseRightButtonDown="ListBox_PreviewMouseRightButtonDown"
PreviewMouseLeftButtonDown="ListBox_PreviewLeftMouseDown"
Margin="10,10,10,10"
Grid.Column="1"
Grid.Row="1"
x:Name="LstBox">
<ListBox.Template>
<ControlTemplate>
<Border>
<Border.Background>
<LinearGradientBrush StartPoint="0,0" EndPoint="1,1" Opacity=".3">
<GradientStop Color="Black" Offset="0"/>
<GradientStop Color="LightGray" Offset="1"/>
</LinearGradientBrush>
</Border.Background>
<ScrollViewer VerticalScrollBarVisibility="Auto" HorizontalScrollBarVisibility="Auto">
<Border>
<Border.Background>
<VisualBrush TileMode="Tile"
Viewport="0,0,36,36" ViewportUnits="Absolute"
Viewbox="0,0,20,20" ViewboxUnits="Absolute">
<VisualBrush.Visual>
<Rectangle Stroke="Darkgray" StrokeThickness="0.5" Height="24" Width="24"
StrokeDashArray="5 3"/>
</VisualBrush.Visual>
</VisualBrush>
</Border.Background>
<ItemsPresenter/>
</Border>
</ScrollViewer>
</Border>
</ControlTemplate>
</ListBox.Template>
<ListBox.ItemsSource>
<StaticResource ResourceKey="DiagramCol"/>
</ListBox.ItemsSource>
<ListBox.ItemsPanel>
<ItemsPanelTemplate>
<Canvas IsItemsHost="True" Background="#01FFFFFF"
Height="{Binding AreaHeight}" Width="{Binding AreaWidth}"
VerticalAlignment="Bottom" HorizontalAlignment="Left"/>
</ItemsPanelTemplate>
</ListBox.ItemsPanel>
<ListBox.ItemContainerStyle>
<Style TargetType="ListBoxItem">
<Setter Property="Canvas.Left" Value="{Binding X}"/>
<Setter Property="Canvas.Top" Value="{Binding Y}"/>
<Setter Property="FocusVisualStyle" Value="{StaticResource EmptyFocusVisualStyle}"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="ListBoxItem">
<ContentPresenter x:Name="Content"/>
<ControlTemplate.Triggers>
<Trigger Property="IsSelected" Value="True">
<Setter TargetName="Content" Property="Effect">
<Setter.Value>
<DropShadowEffect Color="Gray" ShadowDepth="4" BlurRadius="10"/>
</Setter.Value>
</Setter>
</Trigger>
<DataTrigger Binding="{Binding IsNew}" Value="True">
<Setter Property="Opacity" Value=".5"/>
</DataTrigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</ListBox.ItemContainerStyle>
</ListBox>
<ListBox SelectedItem="{Binding SelectedObject}"
PreviewMouseMove="ListBox_PreviewMouseMove"
PreviewMouseDown="ListBox_PreviewMouseDown"
PreviewMouseRightButtonDown="ListBox_PreviewMouseRightButtonDown"
PreviewMouseLeftButtonDown="ListBox_PreviewLeftMouseDown"
Margin="10,10,10,10"
Grid.Column="1"
Grid.Row="4"
x:Name="SldBox">
<ListBox.Template>
<ControlTemplate>
<Border>
<Border.Background>
<LinearGradientBrush StartPoint="0,0" EndPoint="1,1" Opacity=".3">
<GradientStop Color="Transparent" Offset="0"/>
</LinearGradientBrush>
</Border.Background>
<ScrollViewer VerticalScrollBarVisibility="Auto" HorizontalScrollBarVisibility="Auto">
<Border>
<Border.Background>
<VisualBrush TileMode="Tile"
Viewport="0,0,0,11" ViewportUnits="Absolute"
Viewbox="0,0,20,20" ViewboxUnits="Absolute">
<VisualBrush.Visual>
<Rectangle Stroke="Darkgray" StrokeThickness="0.5" Height="24" Width="24"
StrokeDashArray="5 3"/>
</VisualBrush.Visual>
</VisualBrush>
</Border.Background>
<ItemsPresenter/>
</Border>
</ScrollViewer>
</Border>
</ControlTemplate>
</ListBox.Template>
<ListBox.ItemsSource>
<StaticResource ResourceKey="SliderCol"/>
</ListBox.ItemsSource>
<ListBox.ItemsPanel>
<ItemsPanelTemplate>
<Canvas IsItemsHost="True" Background="#01FFFFFF"
Height="50" Width="{Binding AreaWidth}"
VerticalAlignment="Bottom" HorizontalAlignment="Left"/>
</ItemsPanelTemplate>
</ListBox.ItemsPanel>
<ListBox.ItemContainerStyle>
<Style TargetType="ListBoxItem">
<Setter Property="Canvas.Left" Value="{Binding X}"/>
<Setter Property="Canvas.Top" Value="10"/>
<Setter Property="FocusVisualStyle" Value="{StaticResource EmptyFocusVisualStyle}"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="ListBoxItem">
<ContentPresenter x:Name="Content"/>
<ControlTemplate.Triggers>
<Trigger Property="IsSelected" Value="True">
<Setter TargetName="Content" Property="Effect">
<Setter.Value>
<DropShadowEffect Color="Gray" ShadowDepth="4" BlurRadius="10"/>
</Setter.Value>
</Setter>
</Trigger>
<DataTrigger Binding="{Binding IsNew}" Value="True">
<Setter Property="Opacity" Value=".5"/>
</DataTrigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</ListBox.ItemContainerStyle>
</ListBox>
</Grid>
</Grid>
Please for help. If any question or misunderstanding, please ask:)

Answer 1

You can try
"{Binding ElementName=LstBox, Path=ItemsSource.Count, Converter={StaticResource ItemsSourceCountConverter}}"
And then, change the ElementName to the other ListBox named SldBox. I've provided a path, it's very possible you need another property. To follow your example, you would add the IsSelected one.
Of course you can get rid of that converter, I've added it just as an example.