Run valve isolation trace

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

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

Tap on one or more features to use as filter barriers or create and set the configuration’s filter barriers by selecting a utility category. Toggle “Isolated Features” to update trace configuration. Tap “Trace” to run a subnetwork-based isolation trace. Tap “Reset” to clear filter barriers and trace results.

How it works

1. Create a MapView instance.

2. Create and load a Map with a web map portal item that contains a UtilityNetwork.

3. Create a Map object that contains FeatureLayer(s) created from the service geodatabase’s tables.

4. Create and load a UtilityNetwork with the same feature service URL and map. Use the onSingleTapGesture modifier to listen for tap events on the map view.

5. Create UtilityTraceParameters with isolation trace type and a default starting location from a given asset type and global ID.

6. Get a default UtilityTraceConfiguration from a given tier in a domain network. Set its filter property with an UtilityTraceFilter object.

7. Add a GraphicsOverlay for showing starting location and filter barriers.

8. Populate the choice list for the filter barriers from the categories property of UtilityNetworkDefinition.

9. When the map view is tapped, identify which feature is at the tap location, and add a Graphic to represent a filter barrier.

10. Create a UtilityElement for the identified feature and add this element to the trace parameters’ filterBarriers property.

    • If the element is a junction with more than one terminal, display a terminal picker. Then set the junction’s terminal property with the selected terminal.
    • If it is an edge, set its fractionAlongEdge property using GeometryEngine.polyline(_:fractionalLengthClosestTo:tolerance:) method.

11. If “Trace” is tapped without filter barriers:

    • Create a new UtilityCategoryComparison with the selected category and UtilityCategoryComparison.Operator.exists.
    • Assign this condition to UtilityTraceFilter.barriers from the default configuration from step 6.
    • Update the configuration’s includesIsolatedFeatures property.
    • Set this configuration to the parameters’ traceConfiguration property.
    • Run UtilityNetwork.trace(parameters:) with the specified parameters.

    If “Trace” is tapped with filter barriers:

    • Update includesIsolatedFeatures property of the default configuration from step 6.
    • Run UtilityNetwork.trace(parameters:) with the specified parameters.

12. For every FeatureLayer in this map with trace result elements, select features by converting UtilityElement(s) to ArcGISFeature(s) using UtilityNetwork.features(for:).

Relevant API

• GeometryEngine.polyline(_:fractionalLengthClosestTo:tolerance:)
• ServiceGeodatabase
• UtilityCategory
• UtilityCategoryComparison
• UtilityCategoryComparison.Operator
• UtilityDomainNetwork
• UtilityElement
• UtilityElementTraceResult
• UtilityNetwork
• UtilityNetworkDefinition
• UtilityTerminal
• UtilityTier
• UtilityTraceFilter
• UtilityTraceParameters
• UtilityTraceParameters.TraceType
• UtilityTraceResult

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.

Additional information

Using utility network on ArcGIS Enterprise 10.8 requires an ArcGIS Enterprise member account licensed with the Utility Network user type extension. Please refer to the utility network services documentation.

Tags

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