QueryRelatedFeaturesAsync returns zero results

Question

I've been trying to call QueryRelatedFeaturesAsync to get related features from a feature service, but it's returning zero results. If I call queryRelatedRecords using Rest with the same ObjectID, I correctly get 38 results. I was actually getting related features returned at some point last week, but it looks like I'm missing something now. I've tried a few things: IdentifyLayerResult results = await esriMap.IdentifyLayerAsync(_myFeatureLayer, e.Position, 10, false); //correct feature is loaded ArcGISFeature myFeature; = (ArcGISFeature)results.GeoElements[0]; //returns zero results IReadOnlyList relatedFeaturesResult = await myFeatureTable.QueryRelatedFeaturesAsync(myFeature); I tried adding query parameters: ArcGISFeatureTable myFeatureTable = ArcGISFeatureTable)myFeature.FeatureTable; //returns the correct relationship info RelationshipInfo commentsRelationshipInfo = myFeatureTable.LayerInfo.RelationshipInfos.FirstOrDefault(); RelatedQueryParameters relatedQueryParams = new RelatedQueryParameters(commentsRelationshipInfo) { ReturnGeometry = true }; //returns zero results IReadOnlyList relatedFeaturesResult = await myFeatureTable.QueryRelatedFeaturesAsync(myFeature, relatedQueryParams); I also tried force loading the feature table: await myFeature.LoadAsync(); await myFeature.FeatureTable.LoadAsync(); ArcGISFeatureTable myFeatureTable = ArcGISFeatureTable)myFeature.FeatureTable; //returns the correct relationship info RelationshipInfo commentsRelationshipInfo = myFeatureTable.LayerInfo.RelationshipInfos.FirstOrDefault(); RelatedQueryParameters relatedQueryParams = new RelatedQueryParameters(commentsRelationshipInfo) { ReturnGeometry = true }; //returns zero results IReadOnlyList relatedFeaturesResult = await myFeatureTable.QueryRelatedFeaturesAsync(myFeature, relatedQueryParams);

MattH · Answer

Thank you.

That didn't work directly, but it got me to look in the right place.

At some point, I removed my reference to the related feature layer from the map. I didn't realize that the feature table had to be explicitly added to the map to be found by .QueryRelatedFeaturesAsync()

JoeHershman · Answer

I've only ever done with offline tables, but you could try to explicitly load the related tables and see if that helps

var relatedTables = myFeatureTable .GetRelatedTables();
foreach (var relatedTable in relatedTables)
{
	await relatedTable.LoadAsync();
}

var relatedFeaturesResult = await myFeatureTable.QueryRelatedFeaturesAsync(myFeature);