Tutorial: Add a feature layer

Import modules

1. Import the arcgis.gis module. This module is the entry point into the GIS and provides the functionality to manage GIS content, users, and groups. Additionally, import the Featurelayer class from the arcgis.features module, which has functions for accessing, managing, and displaying features from feature services.

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   from arcgis.gis import GIS
   from arcgis.features import FeatureLayer
   
   
   

2. Log in anonymously to access publicly shared content. The data used in this tutorial is public so you do not need credentials to access it. If it were private data, you would be required to provide authentication.

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   from arcgis.gis import GIS
   from arcgis.features import FeatureLayer
   
   
   portal = GIS()
   
   

Create feature layers using URLs

1. Create a featurelayer instance for each layer by passing the URL in the constructor.

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   portal = GIS()
   
   points_layer = FeatureLayer(
       "https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/Trailheads/FeatureServer/0"
   )
   points_layer
   
   polylines_layer = FeatureLayer(
       "https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/Trails/FeatureServer/0"
   )
   polylines_layer
   
   polygons_layer = FeatureLayer(
       "https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/Parks_and_Open_Space/FeatureServer/0"
   )
   polygons_layer
   
   

Display the feature layers

1. Create a map widget instance by calling the map method and pass in the location of Malibu, CA to set the maps initial extent. Use the add_layer method to add each of the feature layers.

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   points_layer = FeatureLayer(
       "https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/Trailheads/FeatureServer/0"
   )
   points_layer
   
   polylines_layer = FeatureLayer(
       "https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/Trails/FeatureServer/0"
   )
   polylines_layer
   
   polygons_layer = FeatureLayer(
       "https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/Parks_and_Open_Space/FeatureServer/0"
   )
   polygons_layer
   
   map = portal.map("Malibu, CA")
   map
   
   for layer in [points_layer, polylines_layer, polygons_layer]:
       map.add_layer(layer)
   
   

You should see point, line, and polygon features (representing trailheads, trails, and parks) drawn on the map for an area in the Santa Monica Mountains.

Optional: Export the map widget

1. Create a standalone HTML page that can be shared and rendered in a web browser.
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   from os import path, getcwd
   
   export_dir = path.join(getcwd(), "home")
   if not path.isdir(export_dir):
       os.mkdir(export_dir)
   
   export_path = path.join(export_dir, "add-a-feature-layer.html")
   
   map.export_to_html(export_path, title="Add a feature layer")