WPF Validation.Errors Contains Nothing - wpf

Question

I am having problems displaying the Validation.Errors in my ItemsControl. The Validation.Errors does not contain anything. I am NOT using BindingGroup but I use my own custom TextBoxes. Here is the ItemsControl code:
<ItemsControl x:Name="errorList" ItemsSource="{Binding Path = (Validation.Errors), ElementName=gvAddCustomer}" >
<ItemsControl.ItemTemplate>
<DataTemplate>
<TextBlock FontSize="18" Text="{Binding Path=ErrorContent}" />
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
My TextBox uses the ErrorTemplate to display the errors beside the TextBox control and it displays correctly with the error message. Here is the style:
<Style x:Key="TextBoxStyle" TargetType="TextBox">
<Setter Property="Validation.ErrorTemplate">
<Setter.Value>
<ControlTemplate>
<DockPanel LastChildFill="True">
<TextBlock DockPanel.Dock="Right"
Foreground="Orange"
FontSize="12pt"
Text="{Binding ElementName=MyAdorner, Path=AdornedElement.(Validation.Errors)[0].ErrorContent}">
</TextBlock>
<Border BorderBrush="Red" BorderThickness="2">
<AdornedElementPlaceholder Name="MyAdorner" />
</Border>
</DockPanel>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
Can anyone explain why the Validation.Errors contains nothing when I bind to the ItemsControl?

Answer 1

I did my validation very similarly:
<TextBox
Style="{StaticResource TextBoxValidationError}"
Name="PatientFirstName" TabIndex="0">
<TextBox.Text>
<Binding Path="Patient.PatientFirstName" UpdateSourceTrigger="PropertyChanged">
<Binding.ValidationRules>
<bs:NameRequiredRule />
</Binding.ValidationRules>
</Binding>
</TextBox.Text>
</TextBox>
The only drawback is that it does not fire the validation until you enter the first character. You can force it do it in the constructor like this:
System.Windows.Data.BindingExpression be;
DependencyProperty txtProp = System.Windows.Controls.TextBox.TextProperty;
be = PatientFirstName.GetBindingExpression(txtProp);
be.UpdateSource();