Xamarin - adding swipe to a UIVIEW - xamarin

Question

I'm new using Xamarin and I'm trying to learn it by converting an App I built using Titanium in the past. Actually I'm stucked trying to add swipe on my UIView. I checked the documentation and also I found a similar code here in Stack Overflow, but it's not working anyway. Can someone point me what's wrong ? ty !
public partial class ViewController : UIViewController
{
UISwipeGestureRecognizer swipe;
...
}
private void addSwipe()
{
nfloat vpHeight = View.Bounds.Height;
nfloat vpWidth = View.Bounds.Width;
var mainContainer = new UIView()
{
Frame = new CoreGraphics.CGRect(0, 0, vpWidth, vpHeight),
BackgroundColor = UIColor.Red
};
swipe = new UISwipeGestureRecognizer();
mainContainer.AddGestureRecognizer(swipe);
if (swipe.Direction == UISwipeGestureRecognizerDirection.Up)
{
Console.WriteLine("up");
}
}

Answer 1

You need to specify a handler when you create your recognizer:
swipe = new UISwipeGestureRecognizer( (s) =>
{
if (s.Direction == UISwipeGestureRecognizerDirection.Up)
{
Console.WriteLine("up");
}
});

Answer 2

I found the solution on my own...
public partial class ViewController : UIViewController
{
UISwipeGestureRecognizer swipe;
...
}
private void addSwipe()
{
nfloat vpHeight = View.Bounds.Height;
nfloat vpWidth = View.Bounds.Width;
var mainContainer = new UIView()
{
Frame = new CoreGraphics.CGRect(0, 0, vpWidth, vpHeight),
BackgroundColor = UIColor.Red
};
UISwipeGestureRecognizer swipeUp = new UISwipeGestureRecognizer(OnSwipeUp);
swipeUp.Direction = UISwipeGestureRecognizerDirection.Up;
mainContainer.AddGestureRecognizer(swipeUp);
}
private void OnSwipeUp() {
Console.Writeline("Up");
}