ArcGIS API for JavaScript Samples

Find nearest features using Arcade expressions in a popup

2021-11-12T19:29:25Z

This sample demonstrates how to access other features from a layer using the FeatureSet capabilities available in Arcade expressions. When the user clicks a hotel feature in this sample, the Arcade expression executes and finds all restaurants within 500 meters of the hotel. The hotel's distance to each restaurant is then measured. Information for the closest restaurant is then displayed in the hotel's popup.

ReportPlayer - Geoenrichment

2021-11-12T19:27:50Z

The ReportPlayer widget runs infographic report templates for a provided analysis area. This sample allows users to click on one of 4 locations and show one of the Esri provided Infographics for the location. TheReportPlayeruses the GeoEnrichment service to request and create the Infographic.GeoEnrichmentis a subscription based service available through ArcGIS Online. Log-in credentials are always required when executing a GeoEnrichment task.

For demo purposes, this sample requires a user to have ArcGIS Online credentials with access to GeoEnrichment to run successfully.

Relationship Renderer

2021-11-12T19:30:29Z

This sample demonstrates how to generate a relationship renderer to explore the potential relationship between two numeric attributes. This is done by calling the smartMapping.createRelationshipRenderer() method. This sample also demonstrates how you can change the labels, rotation, and colors of the associated legend depending on the information you're trying to convey.

This visualization is commonly known as a bivariate choropleth visualization, which classifies each variable in either 2, 3, or 4 classes along separate color ramps. One of those ramps is rotated 90 degrees and overlaid on the other to create a 2x2, 3x3, or 4x4 square grid. The x-axis indicates the range of values for one variable, and the y-axis indicates the range for the second variable. The squares running diagonal from the lower left corner to the upper right corner indicate features where the two variables may be related or in agreement with one another.

The lower right and upper left corners indicate features where one field has high values and the other field low values and vice versa.

Keep in mind that even if you observe a positive relationship between the two variables of interest, it doesn't mean they are statistically correlated. It also doesn't imply the presence of one variable influences the other. Therefore, this renderer should be used judiciously with some prior knowledge that two variables may likely be related.

Client-side projection

2021-11-12T19:26:26Z

This sample shows how to project features to the spatialReference of the map on the client side.

The all-week-earthquakes geojson is loaded from the USGS site. A point with WGS84 spatial reference is created from each geoJSON feature representing earthquake location. Then each point is projected from WGS84 to Winkel III spatial reference. The final geometries are added to the map as graphics.

The sample also displays the position of the user's cursor as it moves across the map using the coordinateformatter's toLatitudeLongitude() method.

Display more data with FeatureLayer

2021-11-12T19:27:42Z

This sample demonstrates how to enable WebGL rendering on a FeatureLayer. WebGL allows you to display more features in the view and update the renderer of the layer more rapidly.

Create a Geofence with Arcade

2021-11-12T19:31:02Z

This sample demonstrates how to leverage geometry operations within Arcade expressions. A StreamLayer is loaded representing fictional locations for city buses in Los Angeles. The renderer of the layer indicates whether a bus is located within a 3-mile buffer of the LA Convention Center. This is computed using the BufferGeodetic() function included in the Arcade language. Arcade is also used in the popup to compute the distance of each bus from the convention center in miles.

Filter features with clustering enabled

2021-11-12T19:27:27Z

This sample demonstrates how a layer with a UniqueValueRenderer is visualized when featureReduction (e.g. clustering) is enabled. It also shows how the clustering visualization is impacted when filters, or definitionExpressions are set on the layer. Filtering features with clustering enabled can help reveal patterns not easily discernible without any applied aggregation method.

Support for feature reduction is limited to the following scenarios:

The map must have a spatial reference of Web Mercator or WGS84.
FeatureLayer or CSVLayer with point geometries fewer than 50,000 features.
FeatureLayer created from a service URL must point to a service that supports pagination.
When editing is initiated with the Editor widget, then feature reduction is disabled until the Editor widget is destroyed.

Basic clustering

2021-11-12T19:27:23Z

This sample demonstrates how to enable featureReduction (e.g. clustering) on a FeatureLayer. This is handled via the featureReduction constructor option, or the setFeatureReduction() method.

Support for feature reduction is limited to the following scenarios:

The map must have a spatial reference of Web Mercator or WGS84.
FeatureLayer or CSVLayer with point geometries fewer than 50,000 features.
FeatureLayer created from a service URL must point to a service that supports pagination.
When editing is initiated with the Editor widget, then feature reduction is disabled until the Editor widget is destroyed.

Toggle point clustering

2021-11-12T19:27:25Z

This sample highlights the separation between featureReduction (e.g. clustering) and the renderer of a FeatureLayer. While clustering is used for visualization purposes, it is not a property of the renderer; it is a property of the layer. Therefore, when featureReduction is enabled, the renderer is still applied to the layer. If a renderer is driven by a numeric attribute, then each aggregate graphic is visualized using the average value of the features comprising that cluster. If a UniqueValueRenderer is applied to the layer, then each cluster's color represents the predominant value represented by features comprising the cluster.

Support for feature reduction is limited to the following scenarios:

The map must have a spatial reference of Web Mercator or WGS84.
FeatureLayer or CSVLayer with point geometries fewer than 50,000 features.
FeatureLayer created from a service URL must point to a service that supports pagination.
When editing is initiated with the Editor widget, then feature reduction is disabled until the Editor widget is destroyed.

Reference Arcade expressions in PopupTemplate

2021-11-12T19:29:23Z

This sample demonstrates how to display values returned from an Arcade expression in a PopupTemplate defined on a FeatureLayer. Arcade is useful for creating visualizations in a FeatureLayer based on a value calculated from an expression executed on the client. PopupTemplates can reference the same expressions used in renderers to effectively communicate the data-driven visualization.

In this sample, a layer representing U.S. counties is added to the map. Each feature contains attributes related to labor statistics in the county. The fields include the unemployment rate, population, and total employment. Arcade is used to calculate the labor force participation of each county.

Four arcade expressions are used in the app. Each Arcade expression must be referenced in the expressionInfos property of the PopupTemplate. The expressionInfos is an array of objects that assigns a name and a title to each expression.

The name property is used to reference the expression value in the popupTemplate's content. The name must be prefaced by expression/.

See the Popup profile of the Arcade expressions guide for more information.