Adding a Behavior to a MapView in Xamarin.Forms issue

Question

I'm developing a Xamarin.Forms app with ArcGIS Runtime SDK for .NET. I don't want write code at the Code-Behind of my MapPage.xaml Form, then I wrote a Behavior to capture de ViewpointChanged event and then store the value to a property in the ViewModel class. using Esri.ArcGISRuntime.Xamarin.Forms; using System; using System.Windows.Input; using Xamarin.Forms; namespace TrabajarMapasPortal.Behaviors { public class MapViewViewpointChangedBehavior : BehaviorBase<MapView> { ///

/// ///

public static readonly BindableProperty CommandProperty = BindableProperty.Create("Command", typeof(ICommand), typeof(MapViewViewpointChangedBehavior)); ///

/// ///

public ICommand Command { get { return (ICommand)GetValue(CommandProperty); } set { SetValue(CommandProperty, value); } } ///

/// ///

protected override void OnAttachedTo(MapView bindable) { base.OnAttachedTo(bindable); bindable.ViewpointChanged += this.MapViewViewpointChanged; } ///

/// ///

/// protected override void OnDetachingFrom(MapView bindable) { base.OnDetachingFrom(bindable); bindable.ViewpointChanged -= this.MapViewViewpointChanged; } ///

/// ///

/// /// private void MapViewViewpointChanged(object sender, EventArgs e) { if (this.Command != null) { MapView mapView = (MapView)sender; if(mapView != null) { var viewpoint= mapView.GetCurrentViewpoint(Esri.ArcGISRuntime.Mapping.ViewpointType.BoundingGeometry); if (this.Command.CanExecute(viewpoint)) { this.Command.Execute(viewpoint); } } } } } } ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍ Then I try to attach the behavior to the MapView in the xaml Form: <ContentPage xmlns="http://xamarin.com/schemas/2014/forms" xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml" xmlns:esriUI="clr-namespace:Esri.ArcGISRuntime.Xamarin.Forms;assembly=Esri.ArcGISRuntime.Xamarin.Forms" xmlns:local="clr-namespace:TrabajarMapasPortal.Shared;assembly=TrabajarMapasPortal" xmlns:vm="clr-namespace:TrabajarMapasPortal.ViewModels;assembly=TrabajarMapasPortal" xmlns:prism="clr-namespace:Prism.Mvvm;assembly=Prism.Forms" prism:ViewModelLocator.AutowireViewModel="True" xmlns:bh="clr-namespace:TrabajarMapasPortal.Behaviors;assembly=TrabajarMapasPortal" x:Class="TrabajarMapasPortal.Views.MapPage"> <Grid> <RowDefinition/> <RowDefinition Height="70"/> <esriUI:MapView x:Name="MapView" Map="{Binding Path=Map}"> <bh:MapViewViewporChangedBehavior Command="{Binding Path=UpdateViewpointCommand}" /> esriUI:MapView> <ListView x:Name="BasemapListBox" ItemsSource="{Binding Path=BasemapChoices}" Grid.Row="0" IsVisible="{Binding Path=IsBasemapListVisible}"> <bh:ListViewItemTappedBehavior Command="{Binding Path=ChangeBasemapCommand}"/> <OnPlatform x:TypeArguments="Color" Android="Black" WinPhone="#6FFFFFFF" /> <OnPlatform x:TypeArguments="Thickness" WinPhone="25" /> ListView> <Grid Grid.Row="1" Margin="5,2"> <ColumnDefinition/> <ColumnDefinition/> <ColumnDefinition/> <Button x:Name="BasemapsButton" Grid.Column="0" Text="Mapa Base" Command="{Binding Path=BaseMapsCommand}" /> <Button x:Name="NewMapButton" Grid.Column="1" Text="Nuevo"/> <Button x:Name="SaveMapButton" Grid.Column="2" Text="Guardar ..." Command="{Binding Path=ShowSaveMapPageCommand}"/> Grid> Grid> ContentPage>‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍ But I get the next error message at compile time: TrabajarMapasPortal.Views.MapPage.xaml(19,10): error : Position 19:10. Type Mapview not found in xmlns clr-namespace:Esri.ArcGISRuntime.Xamarin.Forms; assembly=Esri.ArcGISRuntime.Xamarin.Forms ‍‍‍‍‍‍‍‍‍ This is the ViewModel file: using System; using System.Windows.Input; using System.Threading.Tasks; using Esri.ArcGISRuntime.Mapping; using Esri.ArcGISRuntime.Portal; using Esri.ArcGISRuntime.Security; using Prism.Navigation; using Prism.Events; using Prism.Commands; ///

/// ///

namespace TrabajarMapasPortal.ViewModels { using Events; using Prism.Services; ///

/// ///

public class MapPageViewModel : ViewModelBase { private Map _map; private bool _isBasemapListVisible; private const string ArcGISOnlineUrl = "https://www.arcgis.com/sharing/rest"; public const string AppClientId = "fqCCjw5dkUpIuZba"; private const string OAuthRedirectUrl = "https://developers.arcgis.com"; ///

/// ///

public Map Map { get { return this._map; } set { SetProperty<Map>(ref this._map, value); } } ///

/// ///

private Viewpoint CurrentViewpoint { get; set; } ///

/// ///

public bool IsMapSaved { get { return (this.Map != null && this.Map.Item != null); } } ///

/// ///

public string[] BasemapChoices { get; private set; } ///

/// ///

public bool IsBasemapListVisible { get { return this._isBasemapListVisible; } set { SetProperty<bool>(ref this._isBasemapListVisible, value); } } ///

/// ///

public ICommand BaseMapsCommand { get; private set; } ///

/// ///

public ICommand ChangeBasemapCommand { get; private set; } ///

/// ///

public ICommand ShowSaveMapPageCommand { get; private set; } ///

/// ///

public ICommand UpdateViewpointCommand { get; private set; } ///

/// ///

public MapPageViewModel(INavigationService navigationService, IEventAggregator eventAgreggator, IPageDialogService dialogService) { this.DialogService = dialogService; this.EventAggregator = eventAgreggator; this.NavigationService = navigationService; this.EventAggregator .GetEvent<SaveMapEvent>() .Subscribe(SaveMapAction); this.Map = new Map(Basemap.CreateStreetsVector()); this.BaseMapsCommand = new DelegateCommand(BaseMapsAction); this.ChangeBasemapCommand = new DelegateCommand<string>(ChangeBasemapAction); this.ShowSaveMapPageCommand = new DelegateCommand(this.ShowSaveMapPageAction); this.UpdateViewpointCommand = new DelegateCommand<Viewpoint>(this.UpdateCurrentViewPointAction); this.BasemapChoices = new string [] { "Topográfico", "Topográfico Vector", "Calles", "Calles Vector", "Imágenes", "Océanos"}; this.UpdateAuthenticationManager(); } ///

/// ///

/// private void UpdateCurrentViewPointAction(Viewpoint vp) { this.CurrentViewpoint = vp; } ///

/// ///

/// private async void SaveMapAction(SaveMapInfo saveMapInfo) { try { var currentViewpoint = this.Map.InitialViewpoint; if (!this.IsMapSaved) { await SaveNewMapAsync(currentViewpoint, saveMapInfo.Title, saveMapInfo.Description, saveMapInfo.Tags); await this.DialogService.DisplayAlertAsync("Mapa Guardado", "Guardado", string.Format("Se guardó {0} en AGOL", saveMapInfo.Title), "OK"); } else { // TODO: update existing portal item } } catch (Exception ex) { await this.DialogService.DisplayAlertAsync("No se pudo guardar el mapa", ex.Message, "OK"); } } ///

/// ///

private void BaseMapsAction() { this.IsBasemapListVisible = true; } ///

/// ///

/// private void ChangeBasemapAction(string basemap) { switch (basemap) { case "Topográfico": this.Map.Basemap = Basemap.CreateTopographic(); break; case "Topográfico Vector": this.Map.Basemap = Basemap.CreateTopographicVector(); break; case "Calles": this.Map.Basemap = Basemap.CreateStreets(); break; case "Calles Vector": this.Map.Basemap = Basemap.CreateStreetsVector(); break; case "Imágenes": this.Map.Basemap = Basemap.CreateImagery(); break; case "Océanos": this.Map.Basemap = Basemap.CreateOceans(); break; } this.IsBasemapListVisible = false; } private async void ShowSaveMapPageAction() { await this.NavigationService.NavigateAsync("SaveMapPage"); var info = new CredentialRequestInfo { AuthenticationType = AuthenticationType.Token, ServiceUri = new Uri(ArcGISOnlineUrl) }; Credential cred = await AuthenticationManager.Current.GetCredentialAsync(info, false); AuthenticationManager.Current.AddCredential(cred); } public override void OnNavigatedFrom(NavigationParameters parameters) { base.OnNavigatedFrom(parameters); } ///

/// ///

/// /// /// /// /// public async Task SaveNewMapAsync(Viewpoint initialViewpoint, string title, string description, string[] tags) { ArcGISPortal agsOnline = await ArcGISPortal.CreateAsync(new Uri("https://www.arcgis.com/sharing/rest")); this.Map.InitialViewpoint = initialViewpoint; await this.Map.SaveAsAsync(agsOnline, null, title, description, tags, null); } ///

/// ///

/// /// public async Task<Credential> CreateCredentialAsync(CredentialRequestInfo info) { Credential credential = null; try { credential = await AuthenticationManager.Current.GenerateCredentialAsync(info.ServiceUri); } catch (Exception ex) { throw (ex); } return credential; } ///

/// ///

private void UpdateAuthenticationManager() { ServerInfo portalServerInfo = new ServerInfo(); portalServerInfo.ServerUri = new Uri(ArcGISOnlineUrl); portalServerInfo.TokenAuthenticationType = TokenAuthenticationType.OAuthImplicit; OAuthClientInfo oAuthInfo = new OAuthClientInfo { ClientId = AppClientId, RedirectUri = new Uri(OAuthRedirectUrl) }; portalServerInfo.OAuthClientInfo = oAuthInfo; AuthenticationManager thisAuthenticationManager = AuthenticationManager.Current; thisAuthenticationManager.RegisterServer(portalServerInfo); thisAuthenticationManager.ChallengeHandler = new ChallengeHandler(CreateCredentialAsync); } } }‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍ Appreciate any help!! Marcelo.

marceloctorres · Accepted Answer

I find the answer after drink a hot cup of coffe! The tag was bad written the right way is like that: ‍‍‍‍