ArcGISRuntimeXamarin.Samples.ManageBookmarks.ManageBookmarks.OnAddBookmarksButtonClicked C# (CSharp) Метод

        private void OnAddBookmarksButtonClicked(object sender, EventArgs e)
        {
            //Create Alert for bookmark name
            var textInputAlertController = UIAlertController.Create("Provide the bookmark name", 
                string.Empty, UIAlertControllerStyle.Alert);
            
            //Add Text Input
            textInputAlertController.AddTextField(textField => { });

            //Add Actions
            var cancelAction = UIAlertAction.Create("Cancel", UIAlertActionStyle.Cancel, null);
            var okayAction = UIAlertAction.Create("Done", UIAlertActionStyle.Default, alertAction =>{
                // Get the name from the text field
                var name = textInputAlertController.TextFields[0].Text;

                // Exit if the name is empty
                if (string.IsNullOrEmpty(name))
                    return;

                // Check to see if there is a bookmark with same name
                bool doesNameExist = _myMapView.Map.Bookmarks.Any(b => b.Name == name);
                if (doesNameExist)
                    return;

                // Create a new bookmark
                Bookmark myBookmark = new Bookmark();
                myBookmark.Name = name;
                // Get the current viewpoint from map and assign it to bookmark 
                myBookmark.Viewpoint = _myMapView.GetCurrentViewpoint(ViewpointType.BoundingGeometry);
                // Add the bookmark to bookmark collection of the map
                _myMapView.Map.Bookmarks.Add(myBookmark);

            });

            textInputAlertController.AddAction(cancelAction);
            textInputAlertController.AddAction(okayAction);

            //Present Alert
            PresentViewController(textInputAlertController, true, null);
        }