Как создать перетаскиваемую булавку в Windows 10, чтобы обеспечить возможность выбора местоположения?

Перейдите по этой ссылке. Они указали точки отображения с помощью XAML. Вместо границы вы можете иметь сетку с фоновым изображением канцелярской кнопки, слушать события манипуляции для этой сетки.

вот код для достижения того, что я сказал выше.

    private void MainPage_Loaded(object sender, RoutedEventArgs e)
        {
            BasicGeoposition snPosition = new BasicGeoposition() { Latitude = 47.7356039173901, Longitude = -122.310697222129

            };
            Geopoint snPoint = new Geopoint(snPosition);

            // Create a XAML border.
            Grid grid = new Grid
            {
                Width=100,
                Height=100,
                Background = new ImageBrush() {ImageSource= new BitmapImage(new Uri("ms-appx:///Assets/icon.png", UriKind.RelativeOrAbsolute)), Stretch = Stretch.UniformToFill}
            };
              grid.ManipulationMode = ManipulationModes.TranslateX|ManipulationModes.TranslateY;
 grid.ManipulationCompleted += Grid_ManipulationCompleted;
            grid.ManipulationDelta +=Grid_ManipulationDelta;
            // Center the map over the POI.
            MapControl1.Center = snPoint;
            MapControl1.ZoomLevel = 14;
            CompositeTransform tran = new CompositeTransform();
            grid.RenderTransform = tran;
            // Add XAML to the map.
            MapControl1.Children.Add(grid);
            MapControl.SetLocation(grid, snPoint);
            MapControl.SetNormalizedAnchorPoint(grid, new Point(0.5, 0.5));
        }  

        private void Grid_ManipulationDelta(object sender, ManipulationDeltaRoutedEventArgs e)
        {
            Grid grid = sender as Grid;
            CompositeTransform xform = grid.RenderTransform as CompositeTransform;


            xform.TranslateX += e.Delta.Translation.X;
            xform.TranslateY += e.Delta.Translation.Y;
         //   Rect point = grid.TransformToVisual(MapControl1).TransformBounds(new Rect(0,0, grid.Width, grid.Height));

            e.Handled = true;
          //  Geopoint gPoint;
           // MapControl1.GetLocationFromOffset(new Point(point.X, point.Y), out gPoint);
           // Debug.WriteLine(gPoint.Position.Latitude);
           // Debug.WriteLine(gPoint.Position.Longitude);
        }

  private void Grid_ManipulationCompleted(object sender, ManipulationCompletedRoutedEventArgs e)
        {
            Grid grid = sender as Grid;
            Rect point = grid.TransformToVisual(MapControl1).TransformBounds(new Rect(0, 0, grid.Width, grid.Height);
            Geopoint gPoint;
            MapControl1.GetLocationFromOffset(new Point(point.X, point.Y), out gPoint);
            Debug.WriteLine(gPoint.Position.Latitude);
            Debug.WriteLine(gPoint.Position.Longitude);
        }

Местоположение, полученное после перетаскивания, не совсем точное. Вы можете провести небольшие исследования и разработки о том, как получить точную точку относительно MapControl

Я не смог получить принятый ответ на работу. После долгих исследований и помощи из этот ответ я наконец заработало. Вот рабочий образец:

    public sealed partial class MainPage : Page
    {
        public MainPage()
        {
            InitializeComponent();

            var position = new Geopoint(new BasicGeoposition
            {
                Latitude = 30.3618,
                Longitude = -91.1067
            });
            var grid = new Grid
            {
                Width = 32,
                Height = 50
            };
            var pushpin = new Image()
            {
                Source = new BitmapImage(new Uri("ms-appx:///Assets/Pushpin.png")),
                Stretch = Stretch.Uniform,
                ManipulationMode = ManipulationModes.TranslateX | ManipulationModes.TranslateY,
                RenderTransform = new TranslateTransform()
            };
            pushpin.ManipulationStarted += Pushpin_ManipulationStarted;
            pushpin.ManipulationDelta += Pushpin_ManipulationDelta;
            pushpin.ManipulationCompleted += Pushpin_ManipulationCompleted;
            grid.Children.Add(pushpin);

            Map.Center = position;
            Map.Children.Add(grid);
            MapControl.SetLocation(grid, position);
            MapControl.SetNormalizedAnchorPoint(grid, new Point(0.5, 1));
        }

        private Geopoint GetPosition(Image pushpin)
        {
            var grid = pushpin.Parent as Grid;
            var anchor = MapControl.GetNormalizedAnchorPoint(grid);
            var offset = pushpin.TransformToVisual(Map).TransformPoint(new Point(grid.Width * anchor.X, grid.Height * anchor.Y));
            Map.GetLocationFromOffset(offset, out Geopoint position);
            return position;
        }

        private void Pushpin_ManipulationCompleted(object sender, ManipulationCompletedRoutedEventArgs e)
        {
            Map.PanInteractionMode = MapPanInteractionMode.Auto;

            var pushpin = sender as Image;
            var grid = pushpin.Parent as Grid;
            var position = GetPosition(pushpin);
            MapControl.SetLocation(grid, position);
            var transform = pushpin.RenderTransform as TranslateTransform;
            transform.X = 0;
            transform.Y = 0;
        }

        private void Pushpin_ManipulationDelta(object sender, ManipulationDeltaRoutedEventArgs e)
        {
            var pushpin = sender as Image;
            var transform = pushpin.RenderTransform as TranslateTransform;
            transform.X += e.Delta.Translation.X;
            transform.Y += e.Delta.Translation.Y;
        }

        private void Pushpin_ManipulationStarted(object sender, ManipulationStartedRoutedEventArgs e)
        {
            Map.PanInteractionMode = MapPanInteractionMode.Disabled;
        }
    }