Issue with bindings on attached properties in Xamarin.Forms - xaml

Question

EDIT: Please, do not post answers on how to implement gestures in Xamarin.Forms - read the entire post first.
I'm creating a swipe gesture handlers as effects using the attached properties (as described in Xamarin guides). Skipping the approach discussion I have a strange issue with attached properties implementation.
Long story short (code below) - XAML bindings to attached properties are not working. The Set\Get...Command methods in my static class are not executed at all. I don't see any Debug.WriteLine() result in app output. The debugger doesn't hit the breakpoints set there as well. The same with ...CommandPropertyChanged() handler.
This is my class for the properties handling:
namespace Core.Effects
{
public static class Gesture
{
public static readonly BindableProperty SwipeLeftCommandProperty =
BindableProperty.CreateAttached("SwipeLeftCommand", typeof(ICommand), typeof(Gesture), null, propertyChanged: SwipeLeftCommandPropertyChanged);
public static readonly BindableProperty SwipeRightCommandProperty =
BindableProperty.CreateAttached("SwipeRightCommand", typeof(ICommand), typeof(Gesture), null, propertyChanged: SwipeRightCommandPropertyChanged);
public static ICommand GetSwipeLeftCommand(BindableObject view)
{
Debug.WriteLine("GetSwipeLeftCommand");
return (ICommand) view.GetValue(SwipeLeftCommandProperty);
}
public static void SetSwipeLeftCommand(BindableObject view, ICommand value)
{
Debug.WriteLine("SetSwipeLeftCommand");
view.SetValue(SwipeLeftCommandProperty, value);
}
public static ICommand GetSwipeRightCommand(BindableObject view)
{
Debug.WriteLine("GetSwipeRightCommand");
return (ICommand) view.GetValue(SwipeRightCommandProperty);
}
public static void SetSwipeRightCommand(BindableObject view, ICommand value)
{
Debug.WriteLine("SetSwipeRightCommand");
view.SetValue(SwipeRightCommandProperty, value);
}
private static void SwipeLeftCommandPropertyChanged(BindableObject bindable, object oldValue, object newValue)
{
Debug.WriteLine("SwipeLeftCommandPropertyChanged");
// ...
}
private static void SwipeRightCommandPropertyChanged(BindableObject bindable, object oldValue, object newValue)
{
Debug.WriteLine("SwipeRightCommandPropertyChanged");
// ...
}
// ...
}
}
and here is how I use it in XAML:
<?xml version="1.0" encoding="UTF-8"?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
xmlns:effects="clr-namespace:Core.Effects"
x:Class="Core.Pages.RequestDetailsPage">
<ContentPage.Content>
<StackLayout Spacing="0"
Padding="0"
VerticalOptions="FillAndExpand"
effects:Gesture.SwipeLeftCommand="{Binding NavigateToPreviousRequestCommand}"
effects:Gesture.SwipeRightCommand="{Binding NavigateToNextRequestCommand}">
I have corresponding commands in my view model (MVVM implemented with FreshMvvm framework):
namespace Core.PageModels
{
public class RequestDetailsPageModel : FreshBasePageModel
{
public IRelayCommand NavigateToNextRequestCommand;
public IRelayCommand NavigateToPreviousRequestCommand;
IRelayCommand is my type deriving from ICommand. The BindingContext is properly set by FreshMvvm (works well in other places on this view).
Any clue what might be wrong?

Answer 1

I have done sample repo on GitHub, Check Below Link.
https://github.com/softlion/XamarinFormsGesture
https://github.com/tkowalczyk/SimpleCustomGestureFrame
http://arteksoftware.com/gesture-recognizers-with-xamarin-forms/

Answer 2

My mistake was pretty simple (and pretty hard to track either). Bindings do not operate on fields but on properties:
namespace Core.PageModels
{
public class RequestDetailsPageModel : FreshBasePageModel
{
public IRelayCommand NavigateToNextRequestCommand {get; set;}
public IRelayCommand NavigateToPreviousRequestCommand {get; set;}