RelativeSource-Binding for UserControl

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I've created a UserControl for displaying a Hyperlink in my application.

The markup of this UserControl looks like:

<UserControl x:Class="MVVMExample.View.UserControls.ActionLink"
             xmlns="http://ift.tt/o66D3f"
             xmlns:x="http://ift.tt/mPTqtT"
             xmlns:mc="http://ift.tt/pzd6Lm" 
             xmlns:d="http://ift.tt/pHvyf2" 
             mc:Ignorable="d" d:DesignHeight="300" d:DesignWidth="300"
             DataContext="{Binding RelativeSource={RelativeSource Self}}">
    <Grid>
        <TextBlock Margin="5">
                <Hyperlink Command="{Binding LinkCommand}" CommandParameter="{Binding LinkCommandParameter}">
                    <TextBlock Text="{Binding LinkText, UpdateSourceTrigger=PropertyChanged}"/>
                </Hyperlink>
        </TextBlock>
    </Grid>
</UserControl>

The DataContext of this UserControl is in the CodeBehind which looks like:

public partial class ActionLink : UserControl, INotifyPropertyChanged
{
    public static readonly DependencyProperty LinkTextProperty = DependencyProperty.Register(
        "LinkText", typeof (string), typeof (ActionLink), new PropertyMetadata(LinkTextChanged));

    public static readonly DependencyProperty LinkCommandParameterProperty = DependencyProperty.Register(
        "LinkCommandParameter", typeof (object), typeof (ActionLink),
        new PropertyMetadata(LinkCommandParameterChanged));

    public static readonly DependencyProperty LinkCommandProperty = DependencyProperty.Register(
        "LinkCommand", typeof (ICommand), typeof (ActionLink), new PropertyMetadata(LinkCommandChanged));

    public ActionLink()
    {
        InitializeComponent();
    }

    public object LinkCommandParameter
    {
        get { return GetValue(LinkCommandParameterProperty); }
        set { SetValue(LinkCommandParameterProperty, value); }
    }

    public string LinkText
    {
        get { return (string) GetValue(LinkTextProperty); }
        set
        {
            SetValue(LinkTextProperty, value);
            OnPropertyChanged();
        }
    }

    public ICommand LinkCommand
    {
        get { return (ICommand) GetValue(LinkCommandProperty); }
        set { SetValue(LinkCommandProperty, value); }
    }

    public event PropertyChangedEventHandler PropertyChanged;

    private static void LinkTextChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {
        ((ActionLink) d).LinkText = (string) e.NewValue;
    }

    private static void LinkCommandParameterChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {
        ((ActionLink) d).LinkCommandParameter = e.NewValue;
    }

    private static void LinkCommandChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {
        ((ActionLink) d).LinkCommand = (ICommand) e.NewValue;
    }

    protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
    {
        PropertyChangedEventHandler handler = PropertyChanged;
        if (handler != null)
        {
            handler(this, new PropertyChangedEventArgs(propertyName));
        }
    }
}

Everything just works fine.

Now if I want to use this UserControl with the Command-Binding I have to do the following:

<userControls:ActionLink LinkText="View customers" LinkCommand="{Binding DataContext.ViewCustomersCommand, RelativeSource={RelativeSource FindAncestor, AncestorType=Window}}"/>

If I use a Button instead I don't have to provide that RelativeSource. Is there a opportunity that I also don't have to provide a RelativeSource on binding properties of custom created UserControls?

asked 1 min ago

Tomtom

3,706

RelativeSource-Binding for UserControl