绑定到userControl的WPF C＃命令不会触发

Question

So, I have created a UserControl which really is an "advanced button". I have implemented Dependency Properties, one of which is ICommand , that is supposed to be bindable further when control is used in an actual Window.

However, for some reason the Command doesn't work.

When I tried an exact same approach on a regular button, everything worked fine (thus it's not the fault of my DelegateCommand implementation or my ViewModel).

I tried to followup on why the bound command doesn't fire, but I couldn't find a reliable reason for it not to.

Here is my UserControl XAML:

<Window x:Class="NoContact.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:NoContact"
    mc:Ignorable="d"
    xmlns:userControls="clr-namespace:NoContact.UserControls"
    Title="MainWindow" Height="800" Width="960" Background="#22282a">
<Border BorderThickness="1" BorderBrush="#ffcd22" Margin="10,10,10,10">
<Grid>
    <Button HorizontalContentAlignment="Stretch" Foreground="{Binding ElementName=ImageButtonUC, Path=Foreground}"
            Background="{Binding ElementName=ImageButtonUC, Path=Background}">
        <DockPanel Width="{Binding ElementName=ImageButtonUC, Path=ActualWidth}">
            <Image Source="{Binding ElementName=ImageButtonUC, Path=Image}" DockPanel.Dock="Left"
                   Height="{Binding ElementName=ImageButtonUC, Path=ActualHeight, Converter={StaticResource HeightConverter}}" 
                   Width="{Binding ElementName=ImageButtonUC, Path=ActualWidth, Converter={StaticResource HeightConverter}}" VerticalAlignment="Center"/>
            <TextBlock Text="{Binding ElementName=ImageButtonUC, Path=Text}" FontSize="17" VerticalAlignment="Center" />
        </DockPanel>
    </Button>
</Grid>
<UserControl.Resources>
    <Style TargetType="{x:Type Button}">
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type Button}">
                    <Border Background="{TemplateBinding Background}">
                        <ContentPresenter Content="{TemplateBinding Content}" HorizontalAlignment="Center" VerticalAlignment="Center" />
                    </Border>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>
</UserControl.Resources>

And here is my UserControl code-behind:

public partial class ImageButton : UserControl
{

    // OTHER IRRELEVANT CLASS PARAMETERS ARE HERE

    public ICommand ClickCommand
    {
        get { return (ICommand)GetValue(ClickCommandProperty); }
        set { SetValue(ClickCommandProperty, value); }
    }

    // OTHER IRRELEVANT DEPENDENCY PROPERTIES ARE HERE

    public static DependencyProperty ClickCommandProperty =
        DependencyProperty.Register("ClickCommand", typeof(ICommand), typeof(ImageButton));

    public ImageButton()
    {
        InitializeComponent();
    }
}

Finally, this is how I use my control:

 <userControls:ImageButton x:Name="phoneButton" ClickCommand="{Binding Path=MyButtonClickCommand}" Style="{StaticResource phoneImageButtonUCStyle}" Text="Telefon" Width="200" Height="100" VerticalAlignment="Top" />

The DataContext of the control is set on a stackpanel, that is wrapped around my control. I have also tried setting it directly on the control, no effect.

Again, doing the same on a regular button works just fine.

Answer 1

I have finally solved the problem - and it was pretty trivial.

I had ommited the most important binding - UserControl's button Command to UserControl's Dependency property.

Changing it like this made it work:

<Button HorizontalContentAlignment="Stretch" Foreground="{Binding ElementName=ImageButtonUC, Path=Foreground}"
        Background="{Binding ElementName=ImageButtonUC, Path=Background}"
        Command="{Binding ElementName=ImageButtonUC, Path=ClickCommand}">