Я действительно хочу, чтобы ImageMapContentField имел розовый фон. Это работает для других моих элементов управления, где я привязываюсь напрямую к чему-либо, но я не могу заставить это работать для элементов управления, у которых есть ContentPresenter.

Я надеюсь, что мне просто не хватает чего-то, что позволило бы родителю зафиксировать проверку.

В соответствии с запросом здесь приведен минимальный пример проблемы:

MainWindow.xaml

<Window x:Class="WpfApp1.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:WpfApp1"
        mc:Ignorable="d"
        Title="MainWindow" Height="350" Width="525">


    <Window.Resources>
        <Style TargetType="local:CustomTextField">
            <Setter Property="Validation.ErrorTemplate">
                <Setter.Value>
                    <ControlTemplate>
                        <Border BorderBrush="Red" BorderThickness="2" CornerRadius="2">
                            <AdornedElementPlaceholder/>
                        </Border>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
            <Style.Triggers>
                <Trigger Property="Validation.HasError" Value="True">
                    <Setter Property="ToolTip" Value="{Binding RelativeSource={x:Static RelativeSource.Self}, Path=(Validation.Errors).CurrentItem.ErrorContent}"/>
                    <Setter Property="Background" Value="LightPink"/>
                </Trigger>
            </Style.Triggers>
        </Style>

        <Style TargetType="local:CustomContentControl">
            <Setter Property="Validation.ErrorTemplate">
                <Setter.Value>
                    <ControlTemplate>
                        <Border BorderBrush="Red" BorderThickness="2" CornerRadius="2">
                            <AdornedElementPlaceholder/>
                        </Border>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
            <Style.Triggers>
                <Trigger Property="Validation.HasError" Value="True">
                    <Setter Property="ToolTip" Value="{Binding RelativeSource={x:Static RelativeSource.Self}, Path=(Validation.Errors).CurrentItem.ErrorContent}"/>
                    <Setter Property="Background" Value="LightPink"/>
                </Trigger>
            </Style.Triggers>
        </Style>
    </Window.Resources>

    <Window.DataContext>
        <local:MyModel />
    </Window.DataContext>
    <StackPanel>
        <local:CustomTextField LabelText="Number 1" Value="{Binding Number1, Mode=TwoWay, NotifyOnValidationError=True, ValidatesOnDataErrors=True, ValidatesOnNotifyDataErrors=True}" />
        <local:CustomContentControl LabelText="Number 2">
            <local:CustomContentControl.DataEntryContent>
                <TextBox Text="{Binding Number2, Mode=TwoWay, NotifyOnValidationError=True, ValidatesOnDataErrors=True, ValidatesOnNotifyDataErrors=True}" />
            </local:CustomContentControl.DataEntryContent>    
        </local:CustomContentControl>
    </StackPanel>
</Window>

CustomTextField.xaml

<UserControl x:Class="WpfApp1.CustomTextField"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             xmlns:local="clr-namespace:WpfApp1"
             mc:Ignorable="d" 
             d:DesignHeight="300" d:DesignWidth="300"
             x:Name="Me">
        <StackPanel>
            <Label Content="{Binding ElementName=Me, Path=LabelText}" />
            <TextBox Text="{Binding ElementName=Me, Path=Value}" />
        </StackPanel>
</UserControl>

CustomTextField.cs

public partial class CustomTextField : UserControl
    {
        public static readonly DependencyProperty LabelTextProperty = DependencyProperty.Register(
                                                        "LabelText", typeof(string), typeof(CustomTextField), new PropertyMetadata(default(string)));

        public static readonly DependencyProperty ValueProperty = DependencyProperty.Register(
                                                        "Value", typeof(string), typeof(CustomTextField), new PropertyMetadata(default(string)));

        public string Value
        {
            get { return (string) GetValue(ValueProperty); }
            set { SetValue(ValueProperty, value); }
        }

        public string LabelText
        {
            get { return (string) GetValue(LabelTextProperty); }
            set { SetValue(LabelTextProperty, value); }
        }

        public CustomTextField()
        {
            InitializeComponent();
        }
    }

CustomContentControl.xaml

<UserControl x:Class="WpfApp1.CustomContentControl"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             xmlns:local="clr-namespace:WpfApp1"
             mc:Ignorable="d" 
             d:DesignHeight="300" d:DesignWidth="300"
             x:Name="Me">
        <Grid>
            <StackPanel>
                <Label Content="{Binding ElementName=Me, Path=LabelText}" />
                <ContentPresenter Content="{Binding DataEntryContent, ElementName=Me}" />
            </StackPanel>
        </Grid>
</UserControl>

CustomContentControl.cs

public partial class CustomContentControl : UserControl
    {
        public static readonly DependencyProperty LabelTextProperty = DependencyProperty.Register(
                                                        "LabelText", typeof(string), typeof(CustomContentControl), new PropertyMetadata(default(string)));

        public static readonly DependencyProperty DataEntryContentProperty = DependencyProperty.Register(
                                                        "DataEntryContent", typeof(object), typeof(CustomContentControl), new PropertyMetadata(default(object)));

        public object DataEntryContent
        {
            get { return (object) GetValue(DataEntryContentProperty); }
            set { SetValue(DataEntryContentProperty, value); }
        }

        public string LabelText
        {
            get { return (string) GetValue(LabelTextProperty); }
            set { SetValue(LabelTextProperty, value); }
        }

        public CustomContentControl()
        {
            InitializeComponent();
        }
    }

MyModel.cs

public class MyModel : INotifyPropertyChanged
    {
        int _number1;
        int _number2;

        public int Number1
        {
            get { return _number1; }
            set
            {
                _number1 = value;
                OnPropertyChanged();
            }
        }

        public int Number2
        {
            get { return _number2; }
            set
            {
                _number2 = value;
                OnPropertyChanged();
            }
        }

        public event PropertyChangedEventHandler PropertyChanged;

        protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
        {
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
        }
    }