public override void ViewDidLoad()
{
base.ViewDidLoad();
ImageView.Layer.BorderColor = UIColor.Green.CGColor;
ImageView.Layer.BorderWidth = 0.0f;
View.Layer.BorderColor = UIColor.Red.CGColor;
// 'UserInteractionEnabled' is needed for drag and drop.
ImageView.UserInteractionEnabled = true;
// Allow dragging.
var dragInteraction = new UIDragInteraction(this);
ImageView.AddInteraction(dragInteraction);
// Allow dropping.
var dropInteraction = new UIDropInteraction(this);
View.AddInteraction(dropInteraction);
}