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ArcGIS Runtime SDK for .NET

Perform valve isolation trace

This code sample is available for these platforms:
View Sample on GitHub

Run a filtered trace to locate operable features that will isolate an area from the flow of network resources.

Image of a utility network with an isolation trace applied to it

Use case

Determine the set of operable features required to stop a network's resource, effectively isolating an area of the network. For example, you can choose to return only accessible and operable valves: ones that are not paved over or rusted shut.

How to use the sample

Create and set the configuration's filter barriers by selecting a category. Check or uncheck 'Include Isolated Features'. Tap 'Trace' to run a subnetwork-based isolation trace.

How it works

  1. Create a MapView.
  2. Create and load a UtilityNetwork with a feature service URL.
  3. Create a Map that contains FeatureLayer(s) that are part of this utility network.
  4. Create a default starting location from a given asset type and global id.
  5. Add a GraphicsOverlay with a Graphic that represents this starting location.
  6. Populate the choice list for the 'Filter Barrier: Category exists' from UtilityNetworkDefinition.Categories.
  7. Get a default UtilityTraceConfiguration from a given tier in a domain network. Set it's Filter with a new UtilityTraceFilter.
  8. When 'Trace' is clicked,
    • Create a new UtilityCategoryComparison with the selected category and UtilityCategoryComparisonOperator.Exists.
    • Assign this condition to TraceFilter.Barriers from the default configuration from step 7. Update this configuration's IncludeIsolatedFeatures property.
    • Create a UtilityTraceParameters with UtilityTraceType.Isolation and default starting location from step 4.
    • Set its TraceConfiguration with this configuration and then, run a UtilityNetwork.TraceAsync.
  9. For every FeatureLayer in the map, select the features returned by GetFeaturesForElementsAsync from the elements matching their NetworkSource.Name with the layer's FeatureTable.Name.

Relevant API

  • UtilityCategory
  • UtilityCategoryComparison
  • UtilityCategoryComparisonOperator
  • UtilityDomainNetwork
  • UtilityElement
  • UtilityElementTraceResult
  • UtilityNetwork
  • UtilityNetworkDefinition
  • UtilityTier
  • UtilityTraceFilter
  • UtilityTraceParameters
  • UtilityTraceResult
  • UtilityTraceType

About the data

The Naperville gas network feature service, hosted on ArcGIS Online, contains a utility network used to run the isolation trace shown in this sample.

Tags

category comparison, condition barriers, isolated features, network analysis, subnetwork trace, trace configuration, trace filter, utility network

Sample Code

<ContentPage
    x:Class="ArcGISRuntimeXamarin.Samples.PerformValveIsolationTrace.PerformValveIsolationTrace"
    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:resources="clr-namespace:Forms.Resources;assembly=ArcGISRuntime">
    <RelativeLayout>
        <esriUI:MapView
            x:Name="MyMapView"
            BindingContext="{x:Reference Name=ResponsiveFormContainer}"
            Style="{StaticResource MapWithFormStyle}" />
        <resources:ResponsiveFormContainer x:Name="ResponsiveFormContainer">
            <StackLayout x:Name="FilterOptions" Orientation="Vertical">
                <Label
                    Margin="5"
                    FontAttributes="Bold"
                    Text="Choose Category for Filter Barrier:" />
                <Grid>
                    <Grid.ColumnDefinitions>
                        <ColumnDefinition Width="*" />
                        <ColumnDefinition Width="auto" />
                    </Grid.ColumnDefinitions>
                    <Picker
                        x:Name="CategoryPicker"
                        Grid.Column="0"
                        Margin="5"
                        ItemDisplayBinding="{Binding Name}"
                        TextColor="Black"
                        VerticalOptions="CenterAndExpand" />
                    <Button
                        Grid.Column="1"
                        Margin="5"
                        Clicked="OnTrace"
                        Text="Trace" />
                </Grid>
                <StackLayout Orientation="Horizontal">
                    <Switch
                        x:Name="IncludeIsolatedFeatures"
                        Margin="5"
                        IsToggled="False" />
                    <Label Text="Include Isolated Features" VerticalOptions="Center" />
                </StackLayout>
            </StackLayout>
        </resources:ResponsiveFormContainer>
        <ActivityIndicator
            x:Name="LoadingIndicator"
            HorizontalOptions="CenterAndExpand"
            IsRunning="True"
            IsVisible="True"
            RelativeLayout.HeightConstraint="{ConstraintExpression Type=RelativeToParent,
                                                                   Property=Height,
                                                                   Factor=1}"
            RelativeLayout.WidthConstraint="{ConstraintExpression Type=RelativeToParent,
                                                                  Property=Width,
                                                                  Factor=1}"
            VerticalOptions="CenterAndExpand" />
    </RelativeLayout>
</ContentPage>
// Copyright 2020 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.Geometry;
using Esri.ArcGISRuntime.Mapping;
using Esri.ArcGISRuntime.Symbology;
using Esri.ArcGISRuntime.UI;
using Esri.ArcGISRuntime.UtilityNetworks;
using System;
using System.Collections.Generic;
using System.Linq;
using Xamarin.Forms;

namespace ArcGISRuntimeXamarin.Samples.PerformValveIsolationTrace
{
    [ArcGISRuntime.Samples.Shared.Attributes.Sample(
        name: "Perform valve isolation trace",
        category: "Utility network",
        description: "Run a filtered trace to locate operable features that will isolate an area from the flow of network resources.",
        instructions: "Create and set the configuration's filter barriers by selecting a category. Check or uncheck 'Include Isolated Features'. Tap 'Trace' to run a subnetwork-based isolation trace.",
        tags: new[] { "category comparison", "condition barriers", "isolated features", "network analysis", "subnetwork trace", "trace configuration", "trace filter", "utility network" })]
    public partial class PerformValveIsolationTrace : ContentPage
    {
        // Feature service for an electric utility network in Naperville, Illinois.
        private const string FeatureServiceUrl = "https://sampleserver7.arcgisonline.com/arcgis/rest/services/UtilityNetwork/NapervilleGas/FeatureServer";
        private const int LineLayerId = 3;
        private const int DeviceLayerId = 0;
        private UtilityNetwork _utilityNetwork;

        // For creating the default trace configuration.
        private const string DomainNetworkName = "Pipeline";
        private const string TierName = "Pipe Distribution System";
        private UtilityTraceConfiguration _configuration;

        // For creating the default starting location.
        private const string NetworkSourceName = "Gas Device";
        private const string AssetGroupName = "Meter";
        private const string AssetTypeName = "Customer";
        private const string GlobalId = "{98A06E95-70BE-43E7-91B7-E34C9D3CB9FF}";
        private UtilityElement _startingLocation;

        public PerformValveIsolationTrace()
        {
            InitializeComponent();
            Initialize();
        }

        private async void Initialize()
        {
            try
            {
                // Disable the UI.
                FilterOptions.IsVisible = false;

                // Create and load the utility network.
                _utilityNetwork = await UtilityNetwork.CreateAsync(new Uri(FeatureServiceUrl));

                // Create a map with layers in this utility network.
                MyMapView.Map = new Map(new Basemap(new Uri("https://www.arcgis.com/home/item.html?id=1970c1995b8f44749f4b9b6e81b5ba45")));
                MyMapView.Map.OperationalLayers.Add(new FeatureLayer(new Uri($"{FeatureServiceUrl}/{LineLayerId}")));
                MyMapView.Map.OperationalLayers.Add(new FeatureLayer(new Uri($"{FeatureServiceUrl}/{DeviceLayerId}")));

                // Get a trace configuration from a tier.
                UtilityDomainNetwork domainNetwork = _utilityNetwork.Definition.GetDomainNetwork(DomainNetworkName) ?? throw new ArgumentException(DomainNetworkName);
                UtilityTier tier = domainNetwork.GetTier(TierName) ?? throw new ArgumentException(TierName);
                _configuration = tier.TraceConfiguration;

                // Create a trace filter.
                _configuration.Filter = new UtilityTraceFilter();

                // Get a default starting location.
                UtilityNetworkSource networkSource = _utilityNetwork.Definition.GetNetworkSource(NetworkSourceName) ?? throw new ArgumentException(NetworkSourceName);
                UtilityAssetGroup assetGroup = networkSource.GetAssetGroup(AssetGroupName) ?? throw new ArgumentException(AssetGroupName);
                UtilityAssetType assetType = assetGroup.GetAssetType(AssetTypeName) ?? throw new ArgumentException(AssetTypeName);
                Guid globalId = Guid.Parse(GlobalId);
                _startingLocation = _utilityNetwork.CreateElement(assetType, globalId);

                // Create a graphics overlay.
                GraphicsOverlay overlay = new GraphicsOverlay();
                MyMapView.GraphicsOverlays.Add(overlay);

                // Display starting location.
                IEnumerable<ArcGISFeature> elementFeatures = await _utilityNetwork.GetFeaturesForElementsAsync(new List<UtilityElement> { _startingLocation });
                MapPoint startingLocationGeometry = elementFeatures.FirstOrDefault().Geometry as MapPoint;
                Symbol symbol = new SimpleMarkerSymbol(SimpleMarkerSymbolStyle.Cross, System.Drawing.Color.LimeGreen, 25d);
                Graphic graphic = new Graphic(startingLocationGeometry, symbol);
                overlay.Graphics.Add(graphic);

                // Set the starting viewpoint.
                await MyMapView.SetViewpointAsync(new Viewpoint(startingLocationGeometry, 3000));

                // Build the choice list for categories populated with the `Name` property of each `UtilityCategory` in the `UtilityNetworkDefinition`.
                CategoryPicker.ItemsSource = _utilityNetwork.Definition.Categories.ToList();
                CategoryPicker.SelectedItem = _utilityNetwork.Definition.Categories.First();

                // Enable the UI.
                FilterOptions.IsVisible = true;
            }
            catch (Exception ex)
            {
                await Application.Current.MainPage.DisplayAlert(ex.GetType().Name, ex.Message, "OK");
            }
            finally
            {
                LoadingIndicator.IsVisible = false;
            }
        }

        private async void OnTrace(object sender, EventArgs e)
        {
            try
            {
                LoadingIndicator.IsVisible = true;

                // Clear previous selection from the layers.
                MyMapView.Map.OperationalLayers.OfType<FeatureLayer>().ToList().ForEach(layer => layer.ClearSelection());

                if (CategoryPicker.SelectedItem is UtilityCategory category)
                {
                    // NOTE: UtilityNetworkAttributeComparison or UtilityCategoryComparison with Operator.DoesNotExists
                    // can also be used. These conditions can be joined with either UtilityTraceOrCondition or UtilityTraceAndCondition.
                    UtilityCategoryComparison categoryComparison = new UtilityCategoryComparison(category, UtilityCategoryComparisonOperator.Exists);

                    // Add the filter barrier.
                    _configuration.Filter.Barriers = categoryComparison;
                }

                // Set the include isolated features property.
                _configuration.IncludeIsolatedFeatures = IncludeIsolatedFeatures.IsToggled;

                // Build parameters for isolation trace.
                UtilityTraceParameters parameters = new UtilityTraceParameters(UtilityTraceType.Isolation, new[] { _startingLocation });
                parameters.TraceConfiguration = _configuration;

                // Get the trace result from trace.
                IEnumerable<UtilityTraceResult> traceResult = await _utilityNetwork.TraceAsync(parameters);
                UtilityElementTraceResult elementTraceResult = traceResult?.FirstOrDefault() as UtilityElementTraceResult;

                // Select all the features from the result.
                if (elementTraceResult?.Elements?.Count > 0)
                {
                    foreach (FeatureLayer layer in MyMapView.Map.OperationalLayers.OfType<FeatureLayer>())
                    {
                        IEnumerable<UtilityElement> elements = elementTraceResult.Elements.Where(element => element.NetworkSource.Name == layer.FeatureTable.TableName);
                        IEnumerable<Feature> features = await _utilityNetwork.GetFeaturesForElementsAsync(elements);
                        layer.SelectFeatures(features);
                    }
                }
            }
            catch (Exception ex)
            {
                await Application.Current.MainPage.DisplayAlert(ex.GetType().Name, ex.Message, "OK");
            }
            finally
            {
                LoadingIndicator.IsVisible = false;
            }
        }
    }
}