public async Task initializeMap()
        {
            List <Pushpin> pushpins = new List <Pushpin>();

            foreach (var client in model.GetAllClients())
            {
                Pushpin pin = new Pushpin {
                    Location = client.location, Background = new SolidColorBrush(Colors.Yellow)
                };
                pushpins.Add(pin);
            }

            //on les rentre dans la carte
            foreach (var pin in pushpins)
            {
                myview.myMap.Children.Add(pin);
            }
        }