Add a feature layer
Learn how to access and display point, line, and polygon features in feature layers.
A feature layer is a dataset in a hosted feature service. Each feature layer contains features with a single geometry type (point, line, or polygon), and a set of attributes. You can use feature layers to store, access, and manage large amounts of geographic data for your applications. You get features from a feature layer by accessing its URL.
In this tutorial, you will use URLs to access and display three different hosted feature layers:
Prerequisites
You need an ArcGIS Developer or ArcGIS Online account to access the dashboard and create an API key.
Steps
Create a new pen
- To get started, either complete the Display a map tutorial or .
Set the API key
To access ArcGIS services, you need an API key.
Go to your dashboard to get an API key.
In CodePen, set the
api
to your key, so it can be used to access basemap layer and location services.Key Use dark colors for code blocks Change line
Add modules
In the
require
statement, add theFeature
module.Layer The ArcGIS Maps SDK for JavaScript is available as AMD modules and ES modules, but this tutorial is based on AMD. The AMD
require
function uses references to determine which modules will be loaded – for example, you can specify"esri/Map"
for loading the Map module. After the modules are loaded, they are passed as parameters (e.g.Map
) to the callback function where they can be used in your application. It is important to keep the module references and callback parameters in the same order. For more information on the different types of modules, visit the Introduction to Tooling guide topic.Use dark colors for code blocks Add line. Change line
Add a point feature layer
Point features are typically displayed in a feature layer on top of all other layers. Use the Feature
class to reference the Trailheads URL and add features to the map.
Go to the Trailheads URL and browse the properties of the layer. Make note of the Name, Type, Drawing Info, and Fields properties.
In CodePen, create a
Feature
and set theLayer url
property.Use dark colors for code blocks Add line. Add line. Add line. Add line. Add
trailheads
to the map.Layer Use dark colors for code blocks Add line. Run the app to view the Trailheads layer in the map.
Add a line feature layer
Line features are typically displayed in a feature layer before points. Use the Feature
class to reference the Trails URL and add features to the map.
Go to the Trails URL and browse the properties of the layer. Make note of the Name, Type, Drawing Info, and Fields properties.
In CodePen, create a
Feature
and set theLayer url
property.Use dark colors for code blocks Add line. Add line. Add line. Add line. Add
trails
to the map with an index ofLayer 0
. This ensures that the layer is added to the top of the array and is drawn beforetrailheads
.Layer Use dark colors for code blocks Add line. Run the app to view the Trails layer in the map.
Add a polygon feature layer
Polygon features are typically displayed in a feature layer before lines. Use the Feature
class to reference the Parks and Open Spaces URL and add features to the map.
Go to the Parks and Open Spaces URL and browse the properties of the layer. Make note of the Name, Type, Drawing Info, and Fields properties.
In CodePen, create a
Feature
and set theLayer url
property.Use dark colors for code blocks Add line. Add line. Add line. Add line. Add
parks
to the map with an index ofLayer 0
. This ensures that the layer is added to the top of the array and is drawn beforetrails
.Layer Use dark colors for code blocks Add line.
Run the app
In CodePen, run your code to display the map.
The map view should display all three feature layers in the map. The map view draws the map in following order:
- Topographic basemap layer
- Parks and Open Spaces (polygons)
- Trails (lines)
- Trailheads (points)
It is important to add feature layers in the correct order so that features are displayed correctly (not overlapping) and so you can interact with the features.
What's next?
Learn how to use additional API features and ArcGIS services in these tutorials: