Create feature collection layer (Portal item)

<UserControl x:Class="ArcGIS.WinUI.Samples.FeatureCollectionLayerFromPortal.FeatureCollectionLayerFromPortal"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:esriUI="using:Esri.ArcGISRuntime.UI.Controls">
    <Grid>
        <esriUI:MapView x:Name="MyMapView" />
        <Border Style="{StaticResource BorderStyle}">
            <Grid>
                <Grid.RowDefinitions>
                    <RowDefinition Height="Auto" />
                    <RowDefinition Height="Auto" />
                </Grid.RowDefinitions>
                <Grid.ColumnDefinitions>
                    <ColumnDefinition Width="Auto" />
                    <ColumnDefinition Width="*" />
                </Grid.ColumnDefinitions>
                <TextBlock Grid.Row="0"
                           Grid.Column="0"
                           VerticalAlignment="Center"
                           FontWeight="SemiBold"
                           Text="Item ID:" />
                <TextBox x:Name="CollectionItemIdTextBox"
                         Grid.Row="0"
                         Grid.Column="1"
                         Margin="5,0,0,0"
                         HorizontalAlignment="Stretch" />
                <Button Grid.Row="1"
                        Grid.Column="0"
                        Grid.ColumnSpan="2"
                        Margin="0,5,0,0"
                        HorizontalAlignment="Stretch"
                        Click="Open_Click"
                        Content="Open from portal item" />
            </Grid>
        </Border>
    </Grid>
</UserControl>

// Copyright 2018 Esri.
//
// Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License.
// You may obtain a copy of the License at: http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific
// language governing permissions and limitations under the License.

using Esri.ArcGISRuntime.Data;
using Esri.ArcGISRuntime.Mapping;
using Esri.ArcGISRuntime.Portal;
using Microsoft.UI.Xaml;
using System;
using System.Threading.Tasks;

namespace ArcGIS.WinUI.Samples.FeatureCollectionLayerFromPortal
{
    [ArcGIS.Samples.Shared.Attributes.Sample(
        name: "Create feature collection layer (Portal item)",
        category: "Layers",
        description: "Create a feature collection layer from a portal item.",
        instructions: "The feature collection is loaded from the Portal item when the sample starts.",
        tags: new[] { "collection", "feature collection", "feature collection layer", "id", "item", "map notes", "portal" })]
    public partial class FeatureCollectionLayerFromPortal
    {
        // Default portal item Id to load features from.
        private const string FeatureCollectionItemId = "32798dfad17942858d5eef82ee802f0b";

        public FeatureCollectionLayerFromPortal()
        {
            InitializeComponent();

            // Create the UI, setup the control references and execute initialization.
            Initialize();
        }

        private void Initialize()
        {
            // Add a default value for the portal item Id.
            CollectionItemIdTextBox.Text = FeatureCollectionItemId;

            // Create a new map with the oceans basemap and add it to the map view.
            Map myMap = new Map(BasemapStyle.ArcGISOceans);
            MyMapView.Map = myMap;
        }

        private async Task OpenFeaturesFromArcGISOnline(string itemId)
        {
            try
            {
                // Open a portal item containing a feature collection.
                ArcGISPortal portal = await ArcGISPortal.CreateAsync();
                PortalItem collectionItem = await PortalItem.CreateAsync(portal, itemId);

                // Verify that the item is a feature collection.
                if (collectionItem.Type == PortalItemType.FeatureCollection)
                {
                    // Create a new FeatureCollection from the item.
                    FeatureCollection featureCollection = new FeatureCollection(collectionItem);

                    // Create a layer to display the collection and add it to the map as an operational layer.
                    FeatureCollectionLayer featureCollectionLayer = new FeatureCollectionLayer(featureCollection)
                    {
                        Name = collectionItem.Title
                    };

                    MyMapView.Map.OperationalLayers.Add(featureCollectionLayer);
                }
                else
                {
                    var messageDlg = new MessageDialog2("Portal item with ID '" + itemId + "' is not a feature collection.", "Feature Collection");
                    await messageDlg.ShowAsync();
                }
            }
            catch (Exception ex)
            {
                var messageDlg = new MessageDialog2("Unable to open item with ID '" + itemId + "': " + ex.Message, "Error");
                await messageDlg.ShowAsync();
            }
        }

        private void Open_Click(object sender, RoutedEventArgs e)
        {
            // Get the portal item Id from the user.
            string collectionItemId = CollectionItemIdTextBox.Text.Trim();

            // Make sure an Id was entered.
            if (String.IsNullOrEmpty(collectionItemId))
            {
                var messageDlg = new MessageDialog2("Please enter a portal item ID", "Feature Collection ID");
                _ = messageDlg.ShowAsync();
                return;
            }

            // Call a function to add the feature collection from the specified portal item.
            _ = OpenFeaturesFromArcGISOnline(collectionItemId);
        }
    }
}