RasterLayer class final
A layer that can visualize raster data (from a raster data source).
In its simplest form, raster data consists of a matrix of cells (or pixels) organized into rows and columns (or a grid) where each cell contains a value representing information. Raster layer can support these main types of raster data sources:
- Raster files - path to a file on the device
- Remote ArcGIS Image services, see ImageServiceRaster
- Raster files within GeoPackages, see GeoPackageRaster
- Mosaic datasets, see MosaicDatasetRaster
You can change how a raster layer is visualized by creating a RasterRenderer and applying it to the layer. Each raster layer supports identify on its individual cells when it is displayed in an ArcGISMapViewController or SceneView. The raster layer adopts the loadable pattern; many of its properties are initialized asynchronously. See Loadable for more information.
If a raster dataset has just one value associated with each cell it is called a single-band raster. For example, in a digital elevation model (DEM) each cell contains one value representing the elevation at that location.
A satellite image, however, commonly has multiple bands representing different wavelengths of the electromagnetic spectrum. Landsat imagery, for example, contains seven bands that represent data from the visible and infrared parts of the spectrum. Rasters are particularly useful for remote sensing tasks, such as monitoring vegetation and seeing through smoke to analyze an active fire.
Raster datasets can be quite large. The size of the dataset depends on the following:
- The geographic extent of the data
- The size of the cells used (resolution)
- The number of bands
As with any data consumed locally, file size can be an issue for storage as well as for transferring datasets over the network.
- Inheritance
-
- Object
- Layer
- ImageAdjustmentLayer
- RasterLayer
- Implemented types
Constructors
- RasterLayer.withItem(Item item)
-
Creates a raster layer from the specified image service portal item.
factory
- RasterLayer.withRaster(Raster raster)
-
Creates a raster layer from the specified raster data source.
factory
Properties
- attribution → String
-
The attribution text for the layer.
no setterinherited
- brightness ↔ double
-
The brightness of the layer.
getter/setter pairinherited
- canChangeVisibility → bool
-
A flag indicating whether the layer content's visibility can be changed.
no setterinherited
- contrast ↔ double
-
The contrast of the layer.
getter/setter pairinherited
- description ↔ String
-
The description for the layer.
getter/setter pairinherited
- fullExtent → Envelope?
-
The full extent of this layer, which is the extent where all layer data is
contained.
no setterinherited
- fullTimeExtent → TimeExtent?
-
The full time extent of the layer.
no setteroverride
- gamma ↔ double
-
The gamma of the layer.
getter/setter pairinherited
- 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
- isTimeFilteringEnabled ↔ bool
-
True if the layer filters data based on its
GeoViewController.timeExtent, false otherwise.
getter/setter pairoverride
- isVisible ↔ bool
-
The layer content's visibility.
getter/setter pairinherited
- item → Item?
-
The item the layer has been created from.
no setterinherited
- 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
-
onFullTimeExtentChanged
→ Stream<
TimeExtent?> -
Sets the callback invoked when the full time extent of the object has
changed.
no setteroverride
-
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
- raster → Raster?
-
The raster data source for this layer.
no setter
- renderer ↔ RasterRenderer?
-
The raster renderer used for this layer.
getter/setter pair
- 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
- supportsTimeFiltering → bool
-
True if the layer supports filtering data based on its time values, false
otherwise.
no setteroverride
- timeInterval → TimeValue?
-
The suggested time slider step size for this time aware layer.
no setteroverride
- timeOffset ↔ TimeValue?
-
The amount of time by which the temporal values of this layer's data
points are offset when displaying it in a GeoViewController.
getter/setter pairoverride
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