When we query for features, by default, only the minimum required attributes required to render it are fetched. The feature is said to be in an "unloaded" state. This behavior is because a service could have any number of fields (hundreds if not thousands), and all these fields are not necessary for rendering the feature on the map or selecting it. So in order to get all the fields, we need to "load" the feature.
Option 1:
You can add the following to the sample code to load the features
self.featureLayer.selectFeatures(withQuery: queryParams, mode: AGSSelectionMode.new) { (queryResult:AGSFeatureQueryResult?, error:Error?) -> Void in
if let error = error {
print(error)
}
if let result = queryResult {
let featureEnumerator = result.featureEnumerator()
while featureEnumerator.hasNextObject() {
let feature = result.featureEnumerator().nextObject() as! AGSArcGISFeature
feature.load(completion: { (featureLoadError) in
print("feature attributes \(feature.attributes)")
})
}
}
}
Option 2:
Alternatively, there is a query method on the `AGSServiceFeatureTable` that can return loaded features (by specifying `queryFeatureFields` param to `.loadAll`. You can then select the features as below:
self.featureTable = self.featureLayer.featureTable as! AGSServiceFeatureTable
self.featureTable.queryFeatures(with: queryParams, queryFeatureFields: .loadAll) { (queryResult:AGSFeatureQueryResult?, error:Error?) in
if let result = queryResult {
print("\(result.featureEnumerator().allObjects.count) feature(s) selected")
print(result.featureEnumerator().nextObject()?.attributes)
self.featureLayer.select(result.featureEnumerator().allObjects)
}
}
More on "loadable" pattern can be found here
Thanks,
Suganya
