ArcGISRuntimeXamarin.Samples.ChangeViewpoint.ChangeViewpoint.OnViewpointsButtonTouch C# (CSharp) Метод

        private void OnViewpointsButtonTouch(object sender, EventArgs e)
        {
            // Initialize an UIAlertController
            UIAlertController viewpointAlert = UIAlertController.Create(
                "Select viewpoint", "", UIAlertControllerStyle.Alert);

            // Add actions to alert. Selecting an option set the new viewpoint
            viewpointAlert.AddAction(UIAlertAction.Create(titles[0], UIAlertActionStyle.Default, 
                async (action) =>
                {
                    // Set Viewpoint using Redlands envelope defined above and a padding of 20
                    await _myMapView.SetViewpointGeometryAsync(RedlandsEnvelope, 20);
                }));
            viewpointAlert.AddAction(UIAlertAction.Create(titles[1], UIAlertActionStyle.Default, 
                async (action) =>
                {
                    // Set Viewpoint so that it is centered on the London coordinates defined above
                    await _myMapView.SetViewpointCenterAsync(LondonCoords);
            
                    // Set the Viewpoint scale to match the specified scale 
                    await _myMapView.SetViewpointScaleAsync(LondonScale);
                }));
            viewpointAlert.AddAction(UIAlertAction.Create(titles[2], UIAlertActionStyle.Default, 
                async (action) =>
                {
                    // Navigate to full extent of the first baselayer before animating to specified geometry
                    await _myMapView.SetViewpointAsync(
                        new Viewpoint(_myMapView.Map.Basemap.BaseLayers.First().FullExtent));
                    
                    // Create a new Viewpoint using the specified geometry
                    var viewpoint = new Viewpoint(EdinburghEnvelope);
                    
                    // Set Viewpoint of MapView to the Viewpoint created above and animate to it using a timespan of 5 seconds
                    await _myMapView.SetViewpointAsync(viewpoint, TimeSpan.FromSeconds(5));
                }));
            PresentViewController(viewpointAlert, true, null);
        }