Expander in listview issue - xaml

Question

I'm new here and I need help.
I have some problem regarding the display of screen that you will find in PJ. I would like to remove the blue when I fly the sub-menu trains lines by Mouse but I can not. Anyone could help me please?
Please find attached a screenshot about how he looks like and The XAML code belonging to it.
<UserControl.Resources>
<BooleanToVisibilityConverter x:Key="BooleanToVisibilityConverter" />
<Style x:Key="MenuMaterialDesignExpanderHeaderToggleButton" TargetType="{x:Type ToggleButton}">
<Setter Property="Background" Value="Transparent" />
<Setter Property="HorizontalAlignment" Value="Left" />
<Setter Property="VerticalAlignment" Value="Center" />
<Setter Property="Margin" Value="16,0,0,0" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type ToggleButton}">
<ContentPresenter VerticalAlignment="Center" Content="{TemplateBinding Content}" />
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<Style x:Key="MenuMaterialDesignExpander" TargetType="{x:Type Expander}">
<Setter Property="Background" Value="Transparent"/>
<Setter Property="BorderBrush" Value="Transparent" />
<Setter Property="Cursor" Value="Hand" />
<Setter Property="Foreground" Value="{DynamicResource PrimaryHueMidBrush}" />
<Setter Property="TextBlock.FontWeight" Value="DemiBold" />
<Setter Property="BorderThickness" Value="1" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type Expander}">
<Grid>
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="ExpansionStates">
<VisualStateGroup.Transitions>
<VisualTransition GeneratedDuration="0" To="Expanded">
<VisualTransition.GeneratedEasingFunction>
<CubicEase EasingMode="EaseOut" />
</VisualTransition.GeneratedEasingFunction>
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="PART_Content" Storyboard.TargetProperty="Visibility">
<DiscreteObjectKeyFrame KeyTime="0" Value="{x:Static Visibility.Visible}" />
</ObjectAnimationUsingKeyFrames>
<DoubleAnimationUsingKeyFrames Storyboard.TargetName="PART_Content" Storyboard.TargetProperty="Opacity">
<EasingDoubleKeyFrame KeyTime="0" Value="0" />
<EasingDoubleKeyFrame KeyTime="0:0:0.3" Value="1" />
</DoubleAnimationUsingKeyFrames>
<DoubleAnimationUsingKeyFrames Storyboard.TargetName="PART_Content" Storyboard.TargetProperty="(FrameworkElement.LayoutTransform).(TransformGroup.Children)[0].(ScaleTransform.ScaleX)">
<EasingDoubleKeyFrame KeyTime="0" Value=".5" />
<EasingDoubleKeyFrame KeyTime="0:0:0.2" Value="1" />
</DoubleAnimationUsingKeyFrames>
<DoubleAnimationUsingKeyFrames Storyboard.TargetName="PART_Content" Storyboard.TargetProperty="(FrameworkElement.LayoutTransform).(TransformGroup.Children)[0].(ScaleTransform.ScaleY)">
<EasingDoubleKeyFrame KeyTime="0" Value="0" />
<EasingDoubleKeyFrame KeyTime="0:0:0.2" Value="1" />
</DoubleAnimationUsingKeyFrames>
</Storyboard>
</VisualTransition>
<VisualTransition GeneratedDuration="0" To="Collapsed">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="PART_Content" Storyboard.TargetProperty="Visibility">
<DiscreteObjectKeyFrame KeyTime="0:0:0.5" Value="{x:Static Visibility.Collapsed}" />
</ObjectAnimationUsingKeyFrames>
<DoubleAnimationUsingKeyFrames Storyboard.TargetName="PART_Content" Storyboard.TargetProperty="Opacity">
<EasingDoubleKeyFrame KeyTime="0" Value="1" />
<EasingDoubleKeyFrame KeyTime="0:0:0.3" Value="0" />
</DoubleAnimationUsingKeyFrames>
<DoubleAnimationUsingKeyFrames Storyboard.TargetName="PART_Content" Storyboard.TargetProperty="(FrameworkElement.LayoutTransform).(TransformGroup.Children)[0].(ScaleTransform.ScaleX)">
<EasingDoubleKeyFrame KeyTime="0" Value="1" />
<EasingDoubleKeyFrame KeyTime="0:0:0.2" Value=".5" />
</DoubleAnimationUsingKeyFrames>
<DoubleAnimationUsingKeyFrames Storyboard.TargetName="PART_Content" Storyboard.TargetProperty="(FrameworkElement.LayoutTransform).(TransformGroup.Children)[0].(ScaleTransform.ScaleY)">
<EasingDoubleKeyFrame KeyTime="0" Value="1" />
<EasingDoubleKeyFrame KeyTime="0:0:0.2" Value="0" />
</DoubleAnimationUsingKeyFrames>
</Storyboard>
</VisualTransition>
</VisualStateGroup.Transitions>
<VisualState x:Name="Expanded">
<Storyboard>
<DoubleAnimationUsingKeyFrames Storyboard.TargetName="PART_Content" Storyboard.TargetProperty="Opacity">
<EasingDoubleKeyFrame KeyTime="0" Value="1" />
</DoubleAnimationUsingKeyFrames>
<DoubleAnimationUsingKeyFrames Storyboard.TargetName="PART_Content" Storyboard.TargetProperty="(FrameworkElement.LayoutTransform).(TransformGroup.Children)[0].(ScaleTransform.ScaleX)">
<EasingDoubleKeyFrame KeyTime="0:0:0" Value="1" />
</DoubleAnimationUsingKeyFrames>
<DoubleAnimationUsingKeyFrames Storyboard.TargetName="PART_Content" Storyboard.TargetProperty="(FrameworkElement.LayoutTransform).(TransformGroup.Children)[0].(ScaleTransform.ScaleY)">
<EasingDoubleKeyFrame KeyTime="0:0:0" Value="1" />
</DoubleAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="PART_Content" Storyboard.TargetProperty="Visibility">
<DiscreteObjectKeyFrame KeyTime="0" Value="{x:Static Visibility.Visible}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="Collapsed">
<Storyboard>
<DoubleAnimationUsingKeyFrames Storyboard.TargetName="PART_Content" Storyboard.TargetProperty="Opacity">
<EasingDoubleKeyFrame KeyTime="0" Value="0" />
</DoubleAnimationUsingKeyFrames>
<DoubleAnimationUsingKeyFrames Storyboard.TargetName="PART_Content" Storyboard.TargetProperty="(FrameworkElement.LayoutTransform).(TransformGroup.Children)[0].(ScaleTransform.ScaleX)">
<EasingDoubleKeyFrame KeyTime="0:0:0" Value=".5" />
</DoubleAnimationUsingKeyFrames>
<DoubleAnimationUsingKeyFrames Storyboard.TargetName="PART_Content" Storyboard.TargetProperty="(FrameworkElement.LayoutTransform).(TransformGroup.Children)[0].(ScaleTransform.ScaleY)">
<EasingDoubleKeyFrame KeyTime="0:0:0" Value="0" />
</DoubleAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="PART_Content" Storyboard.TargetProperty="Visibility">
<DiscreteObjectKeyFrame KeyTime="0" Value="{x:Static Visibility.Collapsed}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
</VisualStateGroup>
<VisualStateGroup x:Name="CommonStates">
<VisualState x:Name="Normal" />
<VisualState x:Name="Disabled">
<Storyboard>
<DoubleAnimation Duration="0"
Storyboard.TargetName="NormalToggleButton"
Storyboard.TargetProperty="Opacity"
To=".25" />
</Storyboard>
</VisualState>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<Grid.RowDefinitions>
<RowDefinition MinHeight="25" />
<RowDefinition />
</Grid.RowDefinitions>
<Border BorderThickness="0">
<Grid>
<ToggleButton x:Name="NormalToggleButton"
Grid.Column="1"
IsChecked="{Binding Path=IsExpanded,
Mode=TwoWay,
RelativeSource={RelativeSource TemplatedParent}}"
Style="{StaticResource MenuMaterialDesignExpanderHeaderToggleButton}">
<ContentPresenter HorizontalAlignment="Stretch"
VerticalAlignment="Center"
ContentSource="Header"
RecognizesAccessKey="True" />
</ToggleButton>
</Grid>
</Border>
<Border Grid.Row="1">
<ContentPresenter Name="PART_Content" RenderTransformOrigin="0,0">
<ContentPresenter.LayoutTransform>
<TransformGroup>
<ScaleTransform ScaleX="0.5" ScaleY="0" />
<SkewTransform />
<RotateTransform />
<TranslateTransform />
</TransformGroup>
</ContentPresenter.LayoutTransform>
</ContentPresenter>
</Border>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</UserControl.Resources>
<Grid Width="300">
<StackPanel Grid.Row="0"
Margin="5"
Orientation="Vertical">
<!-- DatabaseSelection -->
<Button Margin="2"
HorizontalContentAlignment="Stretch"
Command="{Binding AddDatabaseSelectionTabItemCommand}"
ToolTip="{Binding ActivatedDatabaseTitleTooltip}">
<Button.CommandParameter>
<params:TabItemInfo Title="{lex:Loc DatabaseSelection}"
PackIcon="Database"
RegionName="DatabaseSelectionRegion"
Type="Unique" />
</Button.CommandParameter>
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto" />
<ColumnDefinition Width="Auto" />
<ColumnDefinition Width="Auto" />
<ColumnDefinition Width="*" />
</Grid.ColumnDefinitions>
<materialDesign:PackIcon Grid.Column="0"
Width="22"
Height="22"
Margin="0,0,5,0"
Kind="Database" />
<TextBlock Grid.Column="1"
VerticalAlignment="Center"
FontSize="14"
FontWeight="Bold"
Text="{Binding ActivatedDatabaseType}" />
<TextBlock Grid.Column="2"
VerticalAlignment="Center"
FontSize="14"
Text=" - " />
<TextBlock Grid.Column="3"
VerticalAlignment="Center"
FontSize="14"
Text="{Binding ActivatedDatabaseTitle}" />
</Grid>
</Button>
<!-- Explorateur d'éléments -->
<Button Margin="2"
HorizontalContentAlignment="Left"
Command="{Binding AddTabItemCommand}"
Style="{StaticResource MaterialDesignFlatButton}">
<Button.CommandParameter>
<params:TabItemInfo Title="{lex:Loc ItemsExplorer}"
RegionName="ItemsExplorerRegion"
PackIcon="Sitemap"
Type="Unique" />
</Button.CommandParameter>
<StackPanel Orientation="Horizontal">
<materialDesign:PackIcon Width="22"
Height="22"
Margin="0,0,5,0"
Kind="Sitemap" />
<TextBlock VerticalAlignment="Center"
FontSize="14"
Text="{lex:Loc ItemsExplorer}" />
</StackPanel>
</Button>
<!-- Schéma principe -->
<ListView Margin="10,0,0,4"
Background="Transparent"
BorderThickness="0"
ItemsSource="{Binding RelecturesCollection}"
ScrollViewer.HorizontalScrollBarVisibility="Hidden">
<ListView.ItemTemplate>
<DataTemplate>
<Button HorizontalContentAlignment="Left"
Command="{Binding RelativeSource={RelativeSource FindAncestor,
AncestorType={x:Type local:MenuView}},
Path=DataContext.AddTabItemCommand,
Mode=OneTime}"
CommandParameter="{Binding TabItemInfo}"
Style="{StaticResource MaterialDesignFlatButton}">
<Grid Width="250">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto" />
<ColumnDefinition Width="Auto" />
<ColumnDefinition Width="*" />
<ColumnDefinition Width="Auto" />
</Grid.ColumnDefinitions>
<TextBlock Grid.Column="0"
VerticalAlignment="Center"
FontSize="14"
FontWeight="Bold"
Foreground="{Binding TypeSchematique.Color}"
Text="{Binding TypeSchematique.Nom}" />
<TextBlock Grid.Column="1"
Margin="3,0"
VerticalAlignment="Center"
FontSize="14"
FontWeight="Normal"
Text="-" />
<TextBlock Grid.Column="2"
VerticalAlignment="Center"
FontSize="14"
FontWeight="Normal"
Text="{Binding Nom}"
TextTrimming="CharacterEllipsis"
ToolTip="{Binding Nom}" />
<TextBlock Grid.Column="3"
Margin="3,0,0,0"
VerticalAlignment="Center"
FontSize="14"
FontStyle="Italic"
FontWeight="Normal"
Text="{Binding Version}" />
</Grid>
</Button>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
<!-- Outils -->
<Expander Margin="0,4"
HorizontalAlignment="Stretch"
IsEnabled="{Binding IsDatabaseActivated}"
IsExpanded="True"
Style="{StaticResource MenuMaterialDesignExpander}">
<Expander.Header>
<StackPanel Cursor="Hand" Orientation="Horizontal">
<materialDesign:PackIcon Width="22"
Height="22"
Margin="0,0,5,0"
Kind="Wrench" />
<TextBlock VerticalAlignment="Center"
FontSize="14"
Text="{lex:Loc Tools}" />
</StackPanel>
</Expander.Header>
<ListView Margin="10,0,0,0"
Background="Transparent"
BorderThickness="0">
<ListViewItem>
<Button HorizontalContentAlignment="Left"
Command="{Binding AddTabItemCommand}"
Style="{StaticResource MaterialDesignFlatButton}">
<Button.CommandParameter>
<params:TabItemInfo Title="{lex:Loc Components}"
RegionName="ComponentLibraryImportRegion"
PackIcon="Import"
Type="Unique" />
</Button.CommandParameter>
<StackPanel Orientation="Horizontal">
<materialDesign:PackIcon Width="22"
Height="22"
Margin="0,0,5,0"
Kind="Import" />
<TextBlock VerticalAlignment="Center"
FontSize="14"
Text="{lex:Loc Components}" />
</StackPanel>
</Button>
</ListViewItem>
<ListViewItem>
<Button HorizontalContentAlignment="Left"
Command="{Binding AddTabItemCommand}"
Style="{StaticResource MaterialDesignFlatButton}">
<Button.CommandParameter>
<params:TabItemInfo Title="{lex:Loc Associations}"
RegionName="ComponentLibraryAssociationRegion"
PackIcon="AutoFix"
Type="Unique" />
</Button.CommandParameter>
<StackPanel Orientation="Horizontal">
<materialDesign:PackIcon Width="22"
Height="22"
Margin="0,0,5,0"
Kind="AutoFix" />
<TextBlock VerticalAlignment="Center"
FontSize="14"
Text="{lex:Loc Associations}" />
</StackPanel>
</Button>
</ListViewItem>
<!--Creer un sous menu dans la View "Trains Vues"-->
<Expander Margin="0,4"
HorizontalAlignment="Stretch"
IsExpanded="True"
Style="{StaticResource MenuMaterialDesignExpander}">
<Expander.Header>
<StackPanel Cursor="Hand" Orientation="Horizontal" >
<materialDesign:PackIcon Width="22"
Height="22"
Margin="0,0,5,0"
Kind="Eye" />
<TextBlock VerticalAlignment="Center"
FontSize="14"
Text="{lex:Loc TrainsViews}" />
</StackPanel>
</Expander.Header>
<ListView Margin="10,0,0,0"
Background="Transparent"
BorderThickness="0">
<!--Sous Sous Menu Lignes Trains-->
<ListViewItem>
<Button HorizontalContentAlignment="Left"
Command="{Binding AddTabItemCommand}"
Style="{StaticResource MaterialDesignFlatButton}">
<Button.CommandParameter>
<params:TabItemInfo Title="{lex:Loc TrainsLines}"
RegionName="ComponentLibraryTrainLinesRegion"
PackIcon="Train"
Type="Unique" />
</Button.CommandParameter>
<StackPanel Orientation="Horizontal">
<materialDesign:PackIcon Width="22"
Height="22"
Margin="0,0,5,0"
Kind="Train" />
<TextBlock VerticalAlignment="Center"
FontSize="14"
Text="{lex:Loc Trainslines}" />
</StackPanel>
</Button>
</ListViewItem>
<!--Sous Sous Menu Options/Variantes-->
<ListViewItem>
<Button HorizontalContentAlignment="Left"
Command="{Binding AddTabItemCommand}"
Style="{StaticResource MaterialDesignFlatButton}">
<Button.CommandParameter>
<params:TabItemInfo Title="{lex:Loc OptionsVersions}"
RegionName="OptionsVersionsRegion"
PackIcon="Check"
Type="Unique" />
</Button.CommandParameter>
<StackPanel Orientation="Horizontal">
<materialDesign:PackIcon Width="22"
Height="22"
Margin="0,0,5,0"
Kind="Check" />
<TextBlock VerticalAlignment="Center"
FontSize="14"
Text="{lex:Loc OptionsVersions}" />
</StackPanel>
</Button>
</ListViewItem>
</ListView>
</Expander>
</ListView>
</Expander>
<ListView Margin="10,0,0,4"
Background="Transparent"
BorderThickness="0"
ItemsSource="{Binding CoherenceCollection}"
ScrollViewer.HorizontalScrollBarVisibility="Hidden">
<ListView.ItemTemplate>
<DataTemplate>
<Button HorizontalContentAlignment="Left"
Command="{Binding RelativeSource={RelativeSource FindAncestor,
AncestorType={x:Type local:MenuView}},
Path=DataContext.AddTabItemCommand,
Mode=OneTime}"
CommandParameter="{Binding TabItemInfo}"
Style="{StaticResource MaterialDesignFlatButton}">
<Grid Width="250">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
</Grid.ColumnDefinitions>
<TextBlock Grid.Column="0"
VerticalAlignment="Center"
FontSize="14"
FontWeight="Bold"
Text="{Binding Nom}" />
</Grid>
</Button>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</StackPanel>
</Grid>