CreateLinkChart(String,KnowledgeGraph,KnowledgeGraphLayerIDSet,String) Method

In This Topic

Creates a link chart map (a map of type MapType.LinkChart) with a specified knowledge graph datastore. This method must be called on the MCT. Use QueuedTask.Run.

Syntax

C#
Visual Basic (Declaration)

public Map CreateLinkChart( 
   string name,
   KnowledgeGraph knowledgeGraph,
   KnowledgeGraphLayerIDSet idSet,
   string templateLinkChartPath
)

Public Overloads Function CreateLinkChart( _
   ByVal name As String, _
   ByVal knowledgeGraph As KnowledgeGraph, _
   ByVal idSet As KnowledgeGraphLayerIDSet, _
   ByVal templateLinkChartPath As String _
) As Map

Parameters

name: The name of the map.
knowledgeGraph: A knowledge graph datastore.
idSet: A set of Named Object types and record ids that sets the content of the Knowledge Graph layer. See KnowledgeGraphLayerIDSet.
templateLinkChartPath: The path to a link chart to use as a template for layout and styling. Use null or an empty string to create the link chart with the default layout and styling. If specified, the template link chart must use the same knowledge graph service as knowledgeGraph.

Return Value

A map of type MapType.LinkChart.

Exceptions

Exception	Description
ArcGIS.Core.CalledOnWrongThreadException	This method or property must be called within the lambda passed to QueuedTask.Run.
System.ArgumentNullException	knowledgeGraph cannot be null.
System.ArgumentException	templateLinkChartPath either does not exist in the current project, is not a Link Chart, does not contain a Knowledge Graph layer or does not contain the same Knowledge Graph datastore as knowledgeGraph.
ArcGIS.Desktop.KnowledgeGraph.KnowledgeGraphLayerException	idSet contains invalid Name Object types..

Remarks

The KnowledgeGraph layer created in the Link Chart contains sub layers for each Named Object type. To set the output content of the KnowledgeGraph composite layer, add an entry to the for each Named Object type to be included in the output along with a list of their relevant record ids. Specify a null or empty list for a given entry to include all the records for that particular type at the time of creation.
Note: Named Object names in a ID set entry are case-sensitive.
If there are Named Object type names specified in the ID set that do not match a Named Object type name in the KnowledgeGraph then a KnowledgeGraphLayerException will be thrown when the layer is created. The exception will contain the list of invalid Named Object types.

If you specify a null or empty IDSet, then the KnowledgeGraph layer will contain all the sub layers for the Named Object types but the sub layers will contain no content.

See KnowledgeGraphLayerIDSet

Example

Create a LinkChart from a subset of an existing LinkChart IDSet

var map = MapView.Active.Map;
if (map.MapType != MapType.LinkChart)
  return;

// find the KG layer
var kgLayer = map.GetLayersAsFlattenedList().OfType<KnowledgeGraphLayer>().FirstOrDefault();
if (kgLayer == null)
  return;

// find the first LinkChartFeatureLayer in the KG layer
var lcFeatureLayer = kgLayer.GetLayersAsFlattenedList().OfType<LinkChartFeatureLayer>().FirstOrDefault();
if (lcFeatureLayer != null)
  return;

QueuedTask.Run(() =>
{
  // get the KG
  var kg = kgLayer.GetDatastore();

  // get the ID set of the KG layer
  var idSet = kgLayer.GetIDSet();

  // get the named object type in the KG that the LinkChartFeatureLayer represents
  var typeName = lcFeatureLayer.GetTypeName();
  // if there are items in the ID Set for this type
  if (idSet.Contains(typeName))
  {
    // build a new ID set containing only these records
    var dict = idSet.ToOIDDictionary();
    var oids = dict[typeName];

    var newDict = new Dictionary<string, List<long>>();
    newDict.Add(typeName, oids);

    var newIDSet = KnowledgeGraphLayerIDSet.FromDictionary(kg, newDict);

    // now create a new link chart using just this subset of records
    MapFactory.Instance.CreateLinkChart("subset LinkChart", kg, newIDSet);
  }
});

Create a link chart based on a template link chart

// note that the template link chart MUST use the same KG server

string url =
        @"https://acme.server.com/server/rest/services/Hosted/AcmeKnowledgeGraph/KnowledgeGraphServer";

QueuedTask.Run(() =>
{
  // find the existing link chart by name
  var projectItem = Project.Current.GetItems<MapProjectItem>()
  .FirstOrDefault(pi => pi.Name == "Acme Link Chart");
  var linkChartMap = projectItem?.GetMap();
  if (linkChartMap == null)
    return;

  //Create a connection properties
  var kg_props =
      new KnowledgeGraphConnectionProperties(new Uri(url));
  try
  {
    //Open a connection
    using (var kg = new KnowledgeGraph(kg_props))
    {
      //Add all entities to the link chart
      var idSet = KnowledgeGraphLayerIDSet.FromKnowledgeGraph(
            kg, KnowledgeGraphFilterType.AllEntities);
      //Create the new link chart and show it
      var newLinkChart = MapFactory.Instance.CreateLinkChart(
                        "KG from Template", kg, idSet, linkChartMap.URI);
      FrameworkApplication.Panes.CreateMapPaneAsync(newLinkChart);
    }
  }
  catch (Exception ex)
  {
    System.Diagnostics.Debug.WriteLine(ex.ToString());
  }
});

Checking KnowledgeGraphLayerException

// running on QueuedTask

var dict = new Dictionary<string, List<long>>();
dict.Add("person", new List<long>());  //Empty list means all records
dict.Add("made_call", null);  //null list means all records

// or specific records - however the ids are obtained
dict.Add("phone_call", new List<long>() { 1, 5, 18, 36, 78 });

// make the id set
var idSet = KnowledgeGraphLayerIDSet.FromDictionary(kg, dict);

try
{
  //Create the link chart and show it
  var linkChart = MapFactory.Instance.CreateLinkChart(
                    "KG With ID Set", kg, idSet);
  FrameworkApplication.Panes.CreateMapPaneAsync(linkChart);
}
catch (KnowledgeGraphLayerException e)
{
  // get the invalid named types
  //   remember that the named types are case-sensitive
  var invalidNamedTypes = e.InvalidNamedTypes;

  // do something with the invalid named types 
  // for example - log or return to caller to show message to user
}

Requirements

Target Platforms: Windows 11, Windows 10

ArcGIS Pro version: 3.3 or higher.

Reference

MapFactory Class
MapFactory Members
Overload List

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