Agfdhyk

I'm trying to achieve quite a specific thing in WPF. I need to create a verifiable control, which will be binded to object of generic class like this

public interface IVerifiable

{

    bool Verified { get; set; }

}



public class VerifiableProperty<T> : INotifyPropertyChanged, IVerifiable

{

    private T _value;

    private bool _verified;



    public T Value

    {

        get => _value;

        set

        {

            if (Equals(value, _value)) return;

            _value = value;

            OnPropertyChanged();

        }

    }



    public bool Verified

    {

        get => _verified;

        set

        {

            if (value == _verified) return;

            _verified = value;

            OnPropertyChanged();

        }

    }

}

I bind controls this way

<TextBox Text="{Binding Path=Number.Value}" att:VerifiableControl.Verified="{Binding Path=Number.Verified}"

                                                 BorderBrush="{Binding Path=(att:VerifiableControl.Verified), Mode=OneWay,

                                                               Converter={StaticResource BackColorVerifiedConverter}}">

                                            <inter:Interaction.Triggers>

                                                <inter:EventTrigger EventName="LostFocus">

                                                    <inter:InvokeCommandAction Command="{Binding Path=DataContext.VerifyCurrentFieldCommand, ElementName=Root}"

                                                                               CommandParameter="{Binding Path=Number}"/>

                                                </inter:EventTrigger>

                                            </inter:Interaction.Triggers>

                                        </TextBox>

Generic value of Verifiable property object binds to text (or SelectedDate in case of DatePicker, etc.), border color binds to flag "Verified" via converter and also I bind interaction trigger for "FocusLost" event to ViewModel command that just set "Verified" flag of corresponding property object to true.

I really don't like the idea I have to copypaste this block many times with little changes. I know, I cannot put intercation trigger in style and I also couldn't find another way to make some kind of short pattern for that.
So, is there a way to create some kind of short pattern for this xaml code where I could customize name of property to bind? Or maybe you could suggest another approach for what I want ot achieve?

Use some attached properties and attach in there to the LostFocus event.

public static class VerifiableBehaviour

{

    public static bool GetVerified(UIElement obj) => (bool)obj.GetValue(VerifiedProperty);

    public static void SetVerified(DependencyObject obj, bool value) => obj.SetValue(VerifiedProperty, value);



    public static readonly DependencyProperty VerifiedProperty = DependencyProperty.RegisterAttached(

        "Verified", typeof(bool), typeof(VerifiableBehaviour),

        new FrameworkPropertyMetadata(false)

        {

            BindsTwoWayByDefault = true,

            DefaultUpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged,

        });



    public static bool GetTracking(UIElement obj) => (bool)obj.GetValue(TrackingProperty);

    public static void SetTracking(UIElement obj, bool value) => obj.SetValue(TrackingProperty, value);



    public static readonly DependencyProperty TrackingProperty = DependencyProperty.RegisterAttached(

        "Tracking", typeof(bool), typeof(VerifiableBehaviour),

        new PropertyMetadata(false, Tracking_PropertyChanged));



    private static void Tracking_PropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)

    {

        UIElement element = d as UIElement;



        if ((bool)e.NewValue)

            element.LostFocus += Element_LostFocus;

        else

            element.LostFocus -= Element_LostFocus;

    }



    private static void Element_LostFocus(object sender, RoutedEventArgs e)

    {

        UIElement element = sender as UIElement;

        SetVerified(element, true);

    }

}

and bind it to your controls

<StackPanel>

    <StackPanel.Resources>

        <DataTemplate x:Key="VerifiableText">

            <StackPanel>

                <TextBox b:VerifiableBehaviour.Tracking="True" 

                         b:VerifiableBehaviour.Verified="{Binding Verified}" 

                         Text="{Binding Value}"/>

                <TextBlock>(Verified: <Run Text="{Binding Verified}"/>)</TextBlock>

            </StackPanel>

        </DataTemplate>

    </StackPanel.Resources>



    <TextBlock Text="MyProperty1"/>

    <ContentControl ContentTemplate="{StaticResource VerifiableText}" 

                    Content="{Binding MyProperty1}" IsTabStop="False"/>

    <Separator/>

    <TextBlock Text="MyProperty2"/>

    <ContentControl ContentTemplate="{StaticResource VerifiableText}" 

                    Content="{Binding MyProperty2}" IsTabStop="False"/>

    <Separator/>

    <TextBlock Text="MyProperty3"/>

    <ContentControl ContentTemplate="{StaticResource VerifiableText}" 

                    Content="{Binding MyProperty3}" IsTabStop="False"/>

    <Separator/>

    <TextBlock Text="MyProperty4"/>

    <ContentControl ContentTemplate="{StaticResource VerifiableText}" 

                    Content="{Binding MyProperty4}" IsTabStop="False"/>

    <Separator/>

</StackPanel>