Add a layer from an item

In this tutorial you will learn how to retrieve a layer stored in ArcGIS Online when you know its Item ID. You will get the layer item using its ID and display the layer on a map.

Prerequisites

Steps

1. Add the following code to model a GIS portal from the ArcGIS API for Python. arcgis.gis is the ArcGIS API for Python GIS model.

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   from arcgis.gis import GIS
   

2. Create a variable to hold the item ID of the public dataset. Any Item hosted on ArcGIS Online has a unique item ID attribute that can be referenced. The data item for this tutorial was prepared in advance, so we retrieved the item ID from the REST endpoint of the data (visible as the id parameter in the query component of the URL in the address bar).

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   from arcgis.gis import GIS
   
   trailheads_id = "883cedb8c9fe4524b64d47666ed234a7"
   
   

3. Create an anonymous connection to ArcGIS Online to retrieve this public data.

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   from arcgis.gis import GIS
   
   trailheads_id = "883cedb8c9fe4524b64d47666ed234a7"
   
   gis = GIS()
   
   

4. Access this data an an ArcGIS Python API item object.

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   from arcgis.gis import GIS
   
   trailheads_id = "883cedb8c9fe4524b64d47666ed234a7"
   
   gis = GIS()
   
   trailheads_item = gis.content.get(trailheads_id)
   trailheads_item
   
   

5. Create a map and add the new layer.

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   from arcgis.gis import GIS
   
   trailheads_id = "883cedb8c9fe4524b64d47666ed234a7"
   
   gis = GIS()
   
   trailheads_item = gis.content.get(trailheads_id)
   trailheads_item
   
   m = gis.map()
   m.add_layer(trailheads_item)
   m
   
   

6. Set the zoom level and center point of the map.

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   from arcgis.gis import GIS
   
   trailheads_id = "883cedb8c9fe4524b64d47666ed234a7"
   
   gis = GIS()
   
   trailheads_item = gis.content.get(trailheads_id)
   trailheads_item
   
   m = gis.map()
   m.add_layer(trailheads_item)
   m
   
   m.center = [34.09042, -118.71511]  # [latitude, longitude]
   m.zoom = 11

Your map should display the locations of trailheads in the Santa Monica Mountains.