I would like to slide the text (marquee text) of the selected item in a combobox, if it's lenght is bigger than the width of the combobox. It can be either automatical or when the user put the mouse over the combobox. The problem is that i have absolutely no idea on how to do that. It's maybe possible to do that with a render transform (previous definition of a textblock inside it)? or with a storyboard?
Here is the xaml that i need to modify
<DataGrid.ColumnHeaderStyle>
<Style TargetType="{x:Type DataGridColumnHeader}">
<Setter Property="ContentTemplate" >
<Setter.Value>
<DataTemplate DataType="DataGridColumnHeader" >
<ComboBox ItemContainerStyle="{StaticResource SingleSelectionComboBoxItem}" DisplayMemberPath="Oggetto" Width="100" Height="20" ItemsSource="{Binding RelativeSource={RelativeSource AncestorType={x:Type DataGrid}},Path=DataContext.Selezione, UpdateSourceTrigger=LostFocus}" SelectionChanged="SingleSelectionComboBox_SelectionChanged"/>
</DataTemplate>
</Setter.Value>
</Setter>
</Style>
</DataGrid.ColumnHeaderStyle>
EDIT: the problem is that i don't know which properties should i target in the storyboard
EDIT2: i took the template of the combobox and modified the text box section like this :
<Style x:Key="ComboBoxEditableTextBox" TargetType="{x:Type TextBox}">
<Style.Triggers>
<EventTrigger RoutedEvent="MouseEnter">
<EventTrigger.Actions>
<BeginStoryboard>
<Storyboard>
<DoubleAnimation From="0" To="100" Duration="00:00:10" Storyboard.TargetProperty="X" Storyboard.TargetName="transferCurreny" RepeatBehavior="Forever" />
</Storyboard>
</BeginStoryboard>
</EventTrigger.Actions>
</EventTrigger>
</Style.Triggers>
<Setter Property="RenderTransform">
<Setter.Value>
<TranslateTransform x:Name="transferCurreny" X="0"/>
</Setter.Value>
</Setter>
The problem is that this seems to have no effect
EDIT 3: i realized that i had to use the template that use the style i mentioned above
<ControlTemplate x:Key="ComboBoxEditableTemplate" TargetType="{x:Type ComboBox}">
<Grid x:Name="Placement" SnapsToDevicePixels="true">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
<ColumnDefinition Width="Auto" />
</Grid.ColumnDefinitions>
<Popup x:Name="PART_Popup" AllowsTransparency="true" Grid.ColumnSpan="2"
IsOpen="{Binding IsDropDownOpen, RelativeSource={RelativeSource TemplatedParent}}"
PopupAnimation="{DynamicResource {x:Static SystemParameters.ComboBoxPopupAnimationKey}}"
Placement="Bottom">
<Themes:SystemDropShadowChrome x:Name="Shdw" Color="Transparent"
MaxHeight="{TemplateBinding MaxDropDownHeight}"
MinWidth="{Binding ActualWidth, ElementName=Placement}">
<Border x:Name="DropDownBorder"
BorderBrush="{DynamicResource {x:Static SystemColors.WindowFrameBrushKey}}"
BorderThickness="1" Background="{DynamicResource {x:Static SystemColors.WindowBrushKey}}">
<ScrollViewer x:Name="DropDownScrollViewer">
<Grid RenderOptions.ClearTypeHint="Enabled">
<Canvas HorizontalAlignment="Left" Height="0" VerticalAlignment="Top" Width="0">
<Rectangle x:Name="OpaqueRect"
Fill="{Binding Background, ElementName=DropDownBorder}"
Height="{Binding ActualHeight, ElementName=DropDownBorder}"
Width="{Binding ActualWidth, ElementName=DropDownBorder}" />
</Canvas>
<ItemsPresenter x:Name="ItemsPresenter"
KeyboardNavigation.DirectionalNavigation="Contained"
SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" />
</Grid>
</ScrollViewer>
</Border>
</Themes:SystemDropShadowChrome>
</Popup>
<Themes:ListBoxChrome x:Name="Border" BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}"
Background="{TemplateBinding Background}" Grid.ColumnSpan="2"
RenderMouseOver="{TemplateBinding IsMouseOver}"
RenderFocused="{TemplateBinding IsKeyboardFocusWithin}" />
<TextBox x:Name="PART_EditableTextBox"
HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}"
IsReadOnly="{Binding IsReadOnly, RelativeSource={RelativeSource TemplatedParent}}"
Margin="{TemplateBinding Padding}" Style="{StaticResource ComboBoxEditableTextBox}"
VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" >
</TextBox>
<ToggleButton Grid.Column="1"
IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}"
Style="{StaticResource ComboBoxToggleButton}" />
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsKeyboardFocusWithin" Value="true">
<Setter Property="Foreground" Value="Black" />
</Trigger>
<Trigger Property="IsDropDownOpen" Value="true">
<Setter Property="RenderFocused" TargetName="Border" Value="true" />
</Trigger>
<Trigger Property="HasItems" Value="false">
<Setter Property="Height" TargetName="DropDownBorder" Value="95" />
</Trigger>
<Trigger Property="IsEnabled" Value="false">
<Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.GrayTextBrushKey}}" />
<Setter Property="Background" Value="#FFF4F4F4" />
</Trigger>
<MultiTrigger>
<MultiTrigger.Conditions>
<Condition Property="IsGrouping" Value="true" />
<Condition Property="VirtualizingPanel.IsVirtualizingWhenGrouping" Value="false" />
</MultiTrigger.Conditions>
<Setter Property="ScrollViewer.CanContentScroll" Value="false" />
</MultiTrigger>
<Trigger Property="HasDropShadow" SourceName="PART_Popup" Value="true">
<Setter Property="Margin" TargetName="Shdw" Value="0,0,5,5" />
<Setter Property="Color" TargetName="Shdw" Value="#71000000" />
</Trigger>
<Trigger Property="ScrollViewer.CanContentScroll" SourceName="DropDownScrollViewer" Value="false">
<Setter Property="Canvas.Top" TargetName="OpaqueRect"
Value="{Binding VerticalOffset, ElementName=DropDownScrollViewer}" />
<Setter Property="Canvas.Left" TargetName="OpaqueRect"
Value="{Binding HorizontalOffset, ElementName=DropDownScrollViewer}" />
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
the textbox section is the one that use the style. However when i do Template="{StaticResource ComboBoxEditableTemplate}" in the combobox, i cannot see the selected item anymore, even if it's not null