Property Overview

Property Details

compressionQualityNumber

The compression quality value. This controls how much loss the image will be subjected to. Only valid when using jpg image format.

compressionToleranceNumber

The output image compression tolerance value.

Default Value:0.01

copyrightString

The copyright text as defined by the image service.

declaredClassStringreadonly inherited

Since: ArcGIS API for JavaScript 4.7

The name of the class. The declared class name is formatted as esri.folder.className.

definitionExpressionString

The SQL where clause used to filter rasters on the client. Only the rasters that satisfy the definition expression are displayed in the View.

domainFieldsField[]

An array of fields in the layer for which a Domain has been defined.

fieldsField[]

An array of fields in the layer. Each field represents an attribute that may contain a value for each raster in the layer.

formatString

The output image type. The default value is lerc if a pixelFilter is set on the layer.

Possible Values: png | png8 | png24 | png32 | jpg | bmp | gif | jpgpng | lerc

Default Value:jpgpng

fullExtentExtent

The full extent of the layer.

hasMultidimensionsBoolean

Indicates if the Image Service has multidimensionalInfo.

hasRasterAttributeTableBoolean

Indicates if the Image Service has a raster attribute table. If true, the raster attribute table can be accessed with the rasterAttributeTable property after the layer has loaded.

idString inherited

The unique ID assigned to the layer. If not set by the developer, it is automatically generated when the layer is loaded.

imageMaxHeightNumber

Since: ArcGIS API for JavaScript 4.4

Indicates the maximum height of the image exported by the service.

Default Value:4100

imageMaxWidthNumber

Since: ArcGIS API for JavaScript 4.4

Indicates the maximum width of the image exported by the service.

Default Value:15000

listModeString inherited

Indicates how the layer should display in the LayerList widget. The possible values are listed below.

Value	Description
show	The layer is visible in the table of contents.
hide	The layer is hidden in the table of contents.
hide-children	If the layer is a GroupLayer, hide the children layers from the table of contents.

Default Value:show

loadedBooleanreadonly inherited

Indicates whether the layer's resources have loaded. When true, all the properties of the object can be accessed.

Default Value:false

loadErrorErrorreadonly inherited

The Error object returned if an error occurred while loading.

Default Value:null

loadStatusStringreadonly inherited

Represents the status of a load operation.

Value	Description
not-loaded	The object's resources have not loaded.
loading	The object's resources are currently loading.
loaded	The object's resources have loaded without errors.
failed	The object's resources failed to load. See loadError for more details.

Default Value:not-loaded

loadWarningsObject[]readonly inherited

A list of warnings which occurred while loading.

maxScaleNumber

The maximum scale (most zoomed in) at which the layer is visible in the view. If the map is zoomed in beyond this scale, the layer will not be visible. A value of 0 means the layer does not have a maximum scale. The maxScale value should always be smaller than the minScale value.

Default Value:0

Examples:

// The layer will not be visible when the view is zoomed in beyond a scale of 1:1,000
layer.maxScale = 1000;

// The layer's visibility is not restricted to a maximum scale.
layer.maxScale = 0;

minScaleNumber

The minimum scale (most zoomed out) at which the layer is visible in the view. If the map is zoomed out beyond this scale, the layer will not be visible. A value of 0 means the layer does not have a minimum scale. The minScale value should always be larger than the maxScale value.

Default Value:0

Examples:

// The layer will not be visible when the view is zoomed out beyond a scale of 1:3,000,000
layer.minScale = 3000000;

// The layer's visibility is not restricted to a minimum scale.
layer.minScale = 0;

mosaicRuleMosaicRule

Defines how overlapping images should be mosaicked.

multidimensionalInfoObject

The multidimensional information associated with the service. This will have a value if serviceInfo has hasMultidimensionalInfo = true.

If defined, multidimensional information contains various "dimensions" of data for a particular value, such as time, depth, altitude, etc. Defining slices of particular dimensions in the layer is handled with the multidimensionalDefinition property of the mosaicRule.

opacityNumber inherited

The opacity of the layer. This value can range between 1 and 0, where 0 is 100 percent transparent and 1 is completely opaque.

Default Value:1

Example:

// Makes the layer 50% transparent
layer.opacity = 0.5;

pixelFilterFunction

A function that processes pixelData. The pixelData object contains a pixelBlock property that gives you access to all of the pixels in the raster on the client.

Inside the pixelFilter you may loop through all the pixels found in the pixelBlock property of the pixelData object and process them. This function may be used to hide some pixels from the view, alter their values, and change their color.

See also:

• Sample - Pixel Filter

Example:

var layer = new ImageryLayer({
  url: // url to the image service
  pixelFilter: colorize  // see the colorize() function below
});

// This function is applied to the pixelFilter property of the layer.
// It takes the original value of each pixel and converts it to an RGB
// representation to color the layer on a blue - red ramp. Blue pixels
// represent low values and red pixels represent high values. View the sample
// referenced above to see how this function works
function colorize(pixelData) {
  // If there isn't pixelData, a pixelBlock, nor pixels, exit the function
  if (pixelData === null || pixelData.pixelBlock === null || pixelData.pixelBlock.pixels === null) {
    return;
  }

  // The pixelBlock stores the values of all pixels visible in the view
  var pixelBlock = pixelData.pixelBlock;

  // Get the min and max values of the data in the current view
  var minValue = pixelBlock.statistics[0].minValue;
  var maxValue = pixelBlock.statistics[0].maxValue;

  // The mask is an array that determines which pixels are visible to the client
  var mask = pixelBlock.mask;

  // The pixels visible in the view
  var pixels = pixelBlock.pixels;

  // The number of pixels in the pixelBlock
  var numPixels = pixelBlock.width * pixelBlock.height;

  // Calculate the factor by which to determine the red and blue
  // values in the colorized version of the layer
  var factor = 255.0 / (maxValue - minValue);

  // Get the pixels containing temperature values in the only band of the data
  var band1 = pixels[0];

  // Create empty arrays for each of the RGB bands to set on the pixelBlock
  var rBand = [];
  var gBand = [];
  var bBand = [];

  // Loop through all the pixels in the view
  for (i = 0; i < numPixels; i++) {
    // Get the pixel value recorded at the pixel location
    var tempValue = band1[i];
    // Calculate the red value based on the factor
    var red = (tempValue - minValue) * factor;

    // Sets a color between blue (lowest) and red (highest) in each band
    rBand[i] = red;
    gBand[i] = 0;
    bBand[i] = 255 - red;
  }

  // Set the new pixel values on the pixelBlock (now three bands)
  pixelData.pixelBlock.pixels = [rBand, gBand, bBand];
  pixelData.pixelBlock.pixelType = "u8"; // u8 is used for color
}

pixelTypeString

The pixel type.

Possible Values: s8 | s16 | s32 | u8 | u16 | u32 | f32 | f64

popupEnabledBoolean

Indicates whether to display popups when the layer is clicked.

Default Value:true

popupTemplatePopupTemplateautocast

The popup template for the layer. When set on the layer, the popupTemplate allows users to access attributes and display their values using text and/or charts in the view's popup when a pixel is clicked. See this sample for an example of how PopupTemplate interacts with an ImageryLayer.

Example:

// displays the temperature stored in the clicked pixel
layer.popupTemplate: {
  title: "Sea Surface Temperature",
  content: "{Raster.ServicePixelValue}° Celsius"
}

portalItemPortalItem

The portal item from which the layer is loaded.

Example:

// loads an ImageryLayer with and ArcGIS Online portal ID
var lyr = new ImageryLayer({
  portalItem: {  // autocasts as new PortalItem()
    id: "28e2f171c1de44de9d6360c11e1c1bae"
  }
});

rasterAttributeTableObject

The raster attribute table associated with the service. To access the raster attribute table, the layer must be loaded.

See also:

• Sample - Raster attribute table

Example:

layer.when(function() {
  if (layer.hasRasterAttributeTable){
    // accesses the raster attribute table of the layer
    var rasterAttributes = layer.rasterAttributeTable.features;
  }
});

rasterAttributeTableFieldPrefixString

Prefix used to define the fields from the raster attribute table. It's primarily used for popups

Default Value:Raster.

rasterFieldsField[]

A complete list of fields that consists of fields from the layer, pixel value fields and the attribute table fields.

refreshIntervalNumber

Since: ArcGIS API for JavaScript 4.6

Refresh interval of the layer in minutes. Minimum refresh interval is 0.1 minute (6 seconds). Value of 0 indicates no refresh.

Default Value:0

Example:

// the layer will be refreshed every 6 seconds.
layer.refreshInterval = 0.1;

renderingRuleRasterFunction

Specifies the rule for how the requested image should be rendered.

See also:

• Raster functions - ArcGIS REST API

Example:

var remapRF = new RasterFunction({
  functionName: "Remap",
  functionArguments: {
    InputRanges: [-3,10,11,37], // remap pixels with values -3 to 10 to now have value of 1
    OutputValues: [1,2],        // remap pixel values from 11 to 37 to have a value of 2
    Raster: "$$"  // Apply Remap to the image service
  },
  outputPixelType: "u8"
});

imageLayer.renderingRule = remapRF; // Set rendering rule to the raster function

spatialReferenceSpatialReferencereadonly

The spatial reference of the image service.

titleString

The title of the layer used to identify it in places such as the Legend and LayerList widgets.

When loading a layer by service url, the title is derived from the service name. If the service has several layers, then the title of each layer will be the concatenation of the service name and the layer name. When the layer is loaded from a portal item, the title of the portal item will be used instead. Finally, if a layer is loaded as part of a webmap or a webscene, then the title of the layer as stored in the webmap/webscene will be used.

tokenStringreadonly

Deprecated

• since version 4.8. Will be removed at version 4.10.

Token generated by the token service using the specified userId and password. The recommended approach to pass a token on a layer is to use IdentityManager.registerToken().

typeStringreadonly

For ImageryLayer the type is imagery.

urlString

The URL to the REST endpoint of the layer. The URL may either point to a resource on ArcGIS Enterprise or ArcGIS Online.

Example:

// This url must point to an Image Service
var layer = new ImageryLayer({
  url: "http://sampleserver6.arcgisonline.com/arcgis/rest/services/CharlotteLAS/ImageServer"
});

versionNumberreadonly

The version of ArcGIS Server in which the image service is published.

Example:

// Prints the version number to the console, e.g. 10.2, 10.3, 10.41
console.log(layer.version);

visibleBoolean inherited

Indicates if the layer is visible in the View. When false, the layer may still be added to a Map instance that is referenced in a view, but its features will not be visible in the view.

Default Value:true

Example:

// The layer is no longer visible in the view
layer.visible = false;

Method Overview

Method Details

cancelLoad()inherited

Cancels a load() operation if it is already in progress.

emit(type, event)inherited

Since: ArcGIS API for JavaScript 4.5

Emits an event on the instance. This method should only be used when creating subclasses of this class.

Parameters:

type String The name of the event.

event Object The event payload.

fetchAttributionData(){Promise<Object>}inherited

Fetches custom attribution data for the layer when it becomes available.

Returns:

Type	Description
Promise<Object>	Resolves to an object containing custom attribution data for the layer.

fetchImage(extent, width, height){Promise<Object>}

Returns an image using the export REST operation that displays data from an ImageryLayer.

Parameters:

extent Extent The extent of the image to export.

width Number The width of the image in pixels.

height Number The height of the image in pixels.

Returns:

Type	Description
Promise<Object>	Resolves to an object containing the parameters of the exported image including the PixelBlock. The pixelBlock contains the value of each pixel in the image. Use this object to call the export REST operation.

hasEventListener(type){Boolean}inherited

Indicates whether there is an event listener on the instance that matches the provided event name.

Parameter:

type String The name of the event.

Returns:

Type	Description
Boolean	Returns true if the class supports the input event.

isFulfilled(){Boolean}inherited

isFulfilled() may be used to verify if creating an instance of the class is fulfilled (either resolved or rejected). If it is fulfilled, true will be returned.

Returns:

Type	Description
Boolean	Indicates whether creating an instance of the class has been fulfilled (either resolved or rejected).

isRejected(){Boolean}inherited

isRejected() may be used to verify if creating an instance of the class is rejected. If it is rejected, true will be returned.

Returns:

Type	Description
Boolean	Indicates whether creating an instance of the class has been rejected.

isResolved(){Boolean}inherited

isResolved() may be used to verify if creating an instance of the class is resolved. If it is resolved, true will be returned.

Returns:

Type	Description
Boolean	Indicates whether creating an instance of the class has been resolved.

load(){Promise}inherited

Loads the resources referenced by this class. This method automatically executes for a View and all of the resources it references in Map if the view is constructed with a map instance.

This method must be called by the developer when accessing a resource that will not be loaded in a View.

Returns:

Type	Description
Promise	Resolves when the resources have loaded.

on(type, listener){Object}inherited

Registers an event handler on the instance. Call this method to hook an event with a listener.

Parameters:

type String The name of event to listen for.

listener Function The function to call when the event is fired.

Returns:

Type	Description
Object	Returns an event handler with a remove() method that can be called to stop listening for the event. Property Type Description remove Function When called, removes the listener from the event.

See also:

• dojo/on

Example:

view.on("click", function(event){
  // event is the event handle returned after the event fires.
  console.log(event.mapPoint);
});

redraw()

Executes the pixelFilter function and redraws the layer.

Example:

// function defined in layer.pixelFilter is re-executed
layer.redraw();

refresh()

Since: ArcGIS API for JavaScript 4.6

Fetches all the data for the layer.

when(callback, errback){Promise}inherited

Since: ArcGIS API for JavaScript 4.6

when() may be leveraged once an instance of the class is created. This method takes two input parameters: a callback function and an errback function. The callback executes when the instance of the class loads. The errback executes if the instance of the class fails to load.

Parameters:

callback Function optional The function to call when the promise resolves.

errback Function optional The function to execute when the promise fails.

Returns:

Type	Description
Promise	Returns a new promise for the result of callback that may be used to chain additional functions.

Example:

// Although this example uses MapView, any class instance that is a promise may use then() in the same way
var view = new MapView();
view.when(function(){
  // This function will execute once the promise is resolved
}, function(error){
  // This function will execute if the promise is rejected due to an error
});

Event Overview

{view: View,layerView: LayerView}

{view: View,layerView: LayerView}

Event Details

layerview-createinherited

Fires after the layer's LayerView is created and rendered in a view.

Properties:

view View The view in which the layerView was created.

layerView LayerView The LayerView rendered in the view representing the layer in layer.

See also:

• View.whenLayerView()

Example:

// This function will fire each time a layer view is created for this
// particular view.
layer.on("layerview-create", function(event){
  // The LayerView for the layer that emitted this event
  event.layerView;
});

layerview-destroyinherited

Fires after the layer's LayerView is destroyed and no longer renders in a view.

Properties:

view View The view in which the layerView was destroyed.

layerView LayerView The destroyed LayerView representing the layer.