topic Re: Python update filter on layer in map in ArcGIS Online Questions

Python update filter on layer in map

Scoth — Wed, 14 Jun 2023 22:50:46 GMT

I'm trying to use the arcgis api for Python to update the filter on a layer in a WebMap. The api reference says there should be a function called "update_layer", but I don't see it on the WebMap object or the layer. Is it out of date or am I missing something?

Either way, I have the layer properties saved in a dictionary, I just need to know how to update the layer now. I know how I would update the Feature Layer itself. But I need to update the layer in the map only.

Also the example given in the reference for how to use this nonexistent function doesn't make sense to me. Seems like there are some typos in this section maybe.

Re: Python update filter on layer in map

Scoth — Wed, 14 Jun 2023 23:04:08 GMT

Nevermind, I realized I need to use get_data() on the map Item object, not the WebMap object. Then adjust the JSON for the layer within the whole map definition. Then I can update the map. Still confused about the "update_layer" function, but whatever.

Re: Python update filter on layer in map

Clubdebambos — Thu, 15 Jun 2023 10:56:06 GMT

Hi @Scoth

You can update the filter in a layer directly in a WebMap with the following...

from arcgis.gis import GIS from arcgis.mapping import WebMap ## access AGOL agol = GIS("home") ## access the WebMap Item wm_item = agol.content.get("WebMap_Item_ID") ## create a WebMap object webmap = WebMap(wm_item) ## get the layer of interest lyr = webmap.get_layer(title="Name of layer as it appears in the WebMap") ## set the filter lyr.layerDefinition.definitionExpression = "FIELDNAME = 'attribute'" # for text field ## update the webmap webmap.update()

Re: Python update filter on layer in map

Clubdebambos — Thu, 15 Jun 2023 11:12:58 GMT

It is more than likely that your version of the arcgis python module is an older version that does not have the update_layer function. When I check for it in version 2.0 it is not there, but it is available in version 2.1.

Re: Python update filter on layer in map

Scoth — Thu, 15 Jun 2023 15:26:08 GMT

Ahh cool. I guess I was kinda looking for a way to update all of the layer properties to match the layer in another map. But your answer works best for my specific question.