Trigger for custom dependency properties in Style

Question

The problem

I defined a reusable control, MyControl, that extends a TextBox.

I want to set a Trigger to one of its dependency properties.
So I added a style to it, with Triggers.

But if I set the TargetType of the Style to MyControl, I get a XAML warning that 'MyControl' TargetType does not match type of element 'TextBlock'.
And if I set it to TextBlock, I get a compilation error that The member "MyDependencyProperty" is not recognized or is not accessible..

• How can I define this style with the triggers?

---

Sample

C# code-behind

namespace UserControls.Local
{
    public partial class MyControl : TextBlock
    {
        #region Trogdor

        public static readonly DependencyProperty TrogdorProperty = DependencyProperty.Register(
            "Trogdor", typeof (bool), typeof (MyControl), new PropertyMetadata(default(bool)));

        public bool Trogdor
        {
            get { return (bool) GetValue(TrogdorProperty); }
            set { SetValue(TrogdorProperty, value); }
        }

        #endregion


        public MyControl()
        {
            InitializeComponent();
        }
    }
}

XAML

<TextBlock
    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:UserControls.Local"
    mc:Ignorable="d"
    Text="BOOP!"
    x:Class="UserControls.Local.MyControl">
    <TextBlock.Style>
        <Style TargetType="{x:Type TextBlock}">
            <Setter Property="Foreground" Value="Blue"/>
            <Style.Triggers>
                <Trigger Property="Trogdor" Value="True">
                    <Setter Property="Foreground" Value="DeepPink"/>
                </Trigger>
            </Style.Triggers>
        </Style>
    </TextBlock.Style>
</TextBlock>

Answer 1

The solution I found was to "fully qualify" the dependency property on the binding:

<Trigger Property="local:MyControl.Trogdor" Value="True">

Answer 2

Not sure if you are still looking for a solution, but the answer in this thread worked for me, while yours didn't.

It uses a DataTrigger with a binding on the root element, instead of a Trigger:

<DataTrigger Binding="{Binding Path=Highlight, RelativeSource={RelativeSource AncestorType={x:Type Elements:DataElement}}}" Value="True">
    <Setter Property="Control.Background" Value="{DynamicResource EntryBoxHighlightBackground}"/>
</DataTrigger>

With your solution, I press the button and the value of the variable changes but the style trigger doesn't apply the changes, like it was not informed of the change in the variable.