Item

Summary

Item provides access to item level information for a UniqueValueRenderer.

Discussion

The Item class allows you to change properties such as label and description and also provides access to the individual Symbol for each item.

Properties

Name	Explanation	Data type
description (Read and Write)	Gets and sets the description for the item.	String
label (Read and Write)	Gets and sets the label for the item.	String
symbol (Read and Write)	Gets and sets the symbol associated with the item.	Symbol
values (Read only)	Gets the list of values associated with each item. There are multiple values when items are grouped within a group.	List

Code sample

Item example

The following script first changes the renderer to a UniqueValueRenderer. Next, it sets the fields property to use a single field called Percent. It next iterates through each Item in each ItemGroup and sets the RGB color to red and the alpha, or opacity, value to match the Percent value of each feature. Finally, it labels each value, sets the symbology back to the layer and saves the output.

import arcpy, os, sys
relpath = os.path.dirname(sys.argv[0])

p = arcpy.mp.ArcGISProject(relpath + r'\\UniqueValue.aprx')
m = p.listMaps('Map')[0]
l = m.listLayers('PercentCover*')[0]
sym = l.symbology

sym.updateRenderer('UniqueValueRenderer')
sym.renderer.fields = ['Percent']
for grp in sym.renderer.groups:
    for itm in grp.items:
        transVal = itm.values[0][0] #Grab the first "percent" value in the list of potential values
        itm.symbol.color = {'RGB': [255, 0, 0, int(transVal)]}
        itm.label = str(transVal) + '%'

l.symbology = sym
p.saveACopy(relpath + r'\\SavedOutput.aprx')