WPF Binding error on creating an element in C# code

Question

Upon dynamically making a TreeViewItem in code, I get binding errors relating to content alignment, even though the associated style specifies this.

TreeViewItem tvi = new TreeViewItem() 
{
    Header = "aString", 
    Style = wpfElement.FindResource("tviRoot") as Style 
};

The error I get is

System.Windows.Data Information: 10 : Cannot retrieve value using the binding and no valid fallback value exists; using default instead. BindingExpression:Path=HorizontalContentAlignment; DataItem=null; target element is 'TreeViewItem' (Name=''); target property is 'HorizontalContentAlignment' (type 'HorizontalAlignment')

(and a similar one for the vertical alignment)

I don't really understand why I get this error and I can't figure it out (I'm not that well-versed in WPF). The weird thing is that everything seems to work as expected, but is still massively slowed down by these errors. Can somebody help?

Edit: I had given the style property a stub name, as I didn't think it mattered, I've renamed it and included its definition below: tviRoot, based on tviBaseStyle

<Style TargetType="TreeViewItem" x:Key="tviBaseStyle">

    <Setter Property="HorizontalContentAlignment" Value="Center" />
    <Setter Property="VerticalContentAlignment" Value="Top" />
    <Setter Property="HorizontalAlignment" Value="Stretch" />
    <Setter Property="VerticalAlignment" Value="Top" />

    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="TreeViewItem">
                <Grid Margin="0">
                    <Grid.RowDefinitions>
                        <!--The top row contains the item's content.-->
                        <RowDefinition Height="{StaticResource rowHeight}" />
                        <!--The bottom row contains the item's children.-->
                        <RowDefinition Height="*" />
                    </Grid.RowDefinitions>
                    <!-- This Border and ContentPresenter displays the content of the TreeViewItem. -->
                    <Border Name="Bd" Margin="0" Padding="0"
                            Background="White" BorderBrush="Gray" BorderThickness="1" CornerRadius="2"
                            TextElement.FontSize="{StaticResource fontSize}"
                            TextElement.FontFamily="{StaticResource fontFamily}">
                        <ContentPresenter ContentSource="Header" HorizontalAlignment="Center" VerticalAlignment="Center" />
                    </Border>
                    <!-- The ItemsPresenter displays the item's children. -->
                    <ItemsPresenter Grid.Row="1"/>
                </Grid>
                <ControlTemplate.Triggers>
                    <Trigger Property="IsSelected" Value="True">
                        <Setter TargetName="Bd" Property="Border.BorderBrush" Value="Red" />
                        <Setter TargetName="Bd" Property="Border.BorderThickness" Value="1"/>
                    </Trigger>
                </ControlTemplate.Triggers>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
    <!-- Make each TreeViewItem show its children in a horizontal StackPanel. -->
    <Setter Property="ItemsPanel">
        <Setter.Value>
            <ItemsPanelTemplate>
                <StackPanel HorizontalAlignment="Center" IsItemsHost="True" Margin="0" Orientation="Horizontal"  />
            </ItemsPanelTemplate>
        </Setter.Value>
    </Setter>
</Style>
<Style x:Key="tviRoot" TargetType="TreeViewItem" BasedOn="{StaticResource tviBaseStyle}">
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="TreeViewItem">
                <Grid Margin="10">
                    <Grid.RowDefinitions>
                        <!--The top row contains the item's content.-->
                        <RowDefinition Height="{StaticResource rowHeight}" />
                        <!--The bottom row contains the item's children.-->
                        <RowDefinition Height="*" />
                    </Grid.RowDefinitions>
                    <!-- This Border and ContentPresenter displays the content of the TreeViewItem. -->
                    <Border Name="Bd" Margin="0" Padding="0"
                            Background="{StaticResource rootGradient}" BorderBrush="Black" BorderThickness="2" CornerRadius="2"
                            TextElement.FontSize="{StaticResource fontSize}"
                            TextElement.FontWeight="Bold"
                            TextElement.FontFamily="{StaticResource fontFamily}">
                        <ContentPresenter ContentSource="Header" HorizontalAlignment="Center" VerticalAlignment="Center"/>
                    </Border>
                    <!-- The ItemsPresenter displays the item's children. -->
                    <ItemsPresenter Grid.Row="1"/>
                </Grid>
                <ControlTemplate.Triggers>
                    <Trigger Property="IsSelected" Value="True">
                        <Setter TargetName="Bd" Property="Border.BorderBrush" Value="Red" />
                        <Setter TargetName="Bd" Property="Border.Background" Value="{StaticResource rootGradientSelected}"/>
                        <Setter TargetName="Bd" Property="TextElement.Foreground" Value="Yellow"/>
                    </Trigger>
                </ControlTemplate.Triggers>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
    <!-- Make each TreeViewItem show its children in a horizontal StackPanel. -->
    <Setter Property="ItemsPanel">
        <Setter.Value>
            <ItemsPanelTemplate>
                <StackPanel HorizontalAlignment="Center" IsItemsHost="True" Margin="0" Orientation="Horizontal"  />
            </ItemsPanelTemplate>
        </Setter.Value>
    </Setter>
</Style>

Answer 1

Okay, changing the order of the creation arguments got rid of the error. (I guess it set the TreeViewItem's Header attribute before associating a Style, and that's what was causing the problem..?) I got a lot more of these errors in my application, so I can't see yet if some new ones didn't pop up somewhere else.