WPF

<!-- ================================== TreeViewNode ================================== -->
<HierarchicalDataTemplate x:Key="TreeNodeTemplate" DataType="{x:Type vm:TreeNodeVM}" ItemsSource="{Binding Children}">
<StackPanel Orientation="Horizontal">
	<Image Width="16" Height="16" Margin="3,0"
			Source="{Binding ImageSource, Converter={StaticResource ImageFromAssetsConverter}}" /><<<< error here
		<TextBlock Text="{Binding NodeLabel}" Margin="3" />
</StackPanel>
</HierarchicalDataTemplate>

xmlns:code="clr-namespace:ClassBuilder.Code">

public MainWindowViewModel()
{
    try
    {
        Action<object> action = handleTask;

        var fb = new FacebookClient(FACEBOOK_ID, FACEBOK_SECRET);

        var task = fb.GetTaskAsync("4");

        task.ContinueWith(action);
    }
    catch (FacebookApiException ex)
    {
        throw ex;
    }
}

private void handleTask(object data)
{
}