FeatureCollectionLayer class final
A layer that can visualize a feature collection.
A feature collection groups logically-related tables of features even though they may have different schema, geometry types, and symbology. A feature collection layer allows multiple tables with different schemas to be managed as a group.
Functional characteristics
Sketch information (called Map Notes in ArcGIS Online), may contain points, lines, polygons, and associated text to describe things in the map. Because they have different schema and geometry types, these features are stored in several distinct tables. A feature collection layer allows these tables to be rendered and managed as a group.
A feature collection can be saved in the map or as a stand-alone portal item. If you need to share the feature collection between several maps, it's best to store it as a separate portal item. If you need to make frequent (near real-time) edits to features in a collection, consider storing these in a feature service instead, because the feature collection is not refreshed until the map or portal item is reloaded. If features are used by a single map or are not subject to frequent updates, it might be best to store them directly in the map. Edits made to features stored in a map will be saved when the map is saved. Edits made to features stored in a portal item (and loaded into a map, for example) must be explicitly saved to the original portal item.
Performance characteristics
Feature collection layers are designed to display a moderate amount of feature data (hundreds or thousands of features). They are ideal for sharing data that is not subject to frequent updates among several clients.
As full feature information is cached locally in a geodatabase and features are drawn natively, this layer type offers excellent display performance when zooming and panning the map, within the extent of cached features.
Downloading features to the device may require extensive network usage and local device storage space. After the features are present on the client, the app no longer needs to make requests for the data. App memory usage increases with the number and complexity of the features in the collection.
Constructors
- FeatureCollectionLayer.withFeatureCollection(FeatureCollection featureCollection)
-
Creates a new feature collection layer object.
factory
Properties
- attribution → String
-
The attribution text for the layer.
no setterinherited
- canChangeVisibility → bool
-
A flag indicating whether the layer content's visibility can be changed.
no setterinherited
- description ↔ String
-
The description for the layer.
getter/setter pairinherited
- featureCollection → FeatureCollection
-
The feature collection associated with this layer.
no setter
- fullExtent → Envelope?
-
The full extent of this layer, which is the extent where all layer data is
contained.
no setterinherited
- hashCode → int
-
The hash code for this object.
no setterinherited
- id ↔ String
-
The unique identifying string for the layer, as specified in a map or
scene.
getter/setter pairinherited
- isIdentifyEnabled → bool
-
True if the layer supports identify, false otherwise.
no setterinherited
- isVisible ↔ bool
-
The layer content's visibility.
getter/setter pairinherited
- item → Item?
-
The item the layer has been created from.
no setterinherited
-
layers
→ List<
FeatureLayer> -
The feature layers associated with this layer.
no setter
- loadError → ArcGISException?
-
The load error.
no setterinherited
- loadStatus → LoadStatus
-
The load status.
no setterinherited
- maxScale ↔ double
-
The maximum scale for the layer.
getter/setter pairinherited
- minScale ↔ double
-
The minimum scale for the layer.
getter/setter pairinherited
- name ↔ String
-
The layer content's name.
getter/setter pairinherited
-
onLoadStatusChanged
→ Stream<
LoadStatus> -
A stream that reports changes to the
LoadStatus.no setterinherited -
onSubLayerContentChanged
→ Stream<
List< LayerContent> > -
Callback invoked when the sublayer content of the layer content have
changed.
no setterinherited
-
onVisibilityChanged
→ Stream<
bool> -
Callback invoked when the visibility of the layer changes.
no setterinherited
- opacity ↔ double
-
The opacity for the layer.
getter/setter pairinherited
- runtimeType → Type
-
A representation of the runtime type of the object.
no setterinherited
- showInLegend ↔ bool
-
A flag indicating whether the layer content participates in the legend.
getter/setter pairinherited
- spatialReference → SpatialReference?
-
The spatial reference of the layer.
no setterinherited
-
subLayerContents
→ List<
LayerContent> -
The sub layer contents of a layer content.
no setterinherited
Methods
-
cancelLoad(
) → void -
Cancels loading metadata for the object.
inherited
-
clone(
) → Layer -
Clones this instance of the layer and its members.
inherited
-
fetchLegendInfos(
) → Future< List< LegendInfo> > -
Fetches the list of legend info.
inherited
-
isVisibleAtScale(
double scale) → bool -
Returns the layer content's effective visibility at the specified scale.
inherited
-
load(
) → Future< void> -
Loads the metadata for the object asynchronously.
inherited
-
noSuchMethod(
Invocation invocation) → dynamic -
Invoked when a nonexistent method or property is accessed.
inherited
-
retryLoad(
) → Future< void> -
Loads or retries loading metadata for the object asynchronously.
inherited
-
toString(
) → String -
A string representation of this object.
inherited
Operators
-
operator ==(
Object other) → bool -
The equality operator.
inherited