topic Re: Symbolization of Non-Null Fields within Polygon Layer in ArcGIS Pro Questions

Symbolization of Non-Null Fields within Polygon Layer

OliverEmily — Fri, 23 May 2025 19:34:21 GMT

I am working on a map of different types of transportation plans in Virginia localities (324 records) and I have hit a roadblock in the most efficient way to display the data. The layer I have created is a polygon layer of locality boundaries and the additional features/attribute fields I would like to display are:

planning district in which each locality resides -- currently symbolized with different fill color for each PDC of which there are 21.

want to display each of these fields as a unique point symbol in each locality for which the respective field is non-null

Bicycle Plans
Multimodal Plans
Active Transportation Plans
Pedestrian Plans
Trail Plans
Other

I plan to provide a legend for the symbolized attributes as well as configure pop-ups for each locality with specific data from the attribute table.

So far, I have come up with the following methods for symbology:

Add a graphics layer and create points manually -- unique symbology respective to each of the above fields.
Create individual layers for each plan type and symbolize by single symbol, unique to each layer/plan type -- layers created from Plans by Locality using select by attribute where respective field values are not null.
1. I would have to offset the symbology of each layer to avoid obscurity
2. Ideally, I would like to contain this data in a single layer but am not opposed to a layer package if necessary as I am unsure of the feasibility in having unique point symbols within a polygon layer.

Other considerations:

Using ArcPro Version 2.9

The data in this layer originated from a standalone attribute table/csv which I joined to a polygon feature layer of Virginia localities. There may be a workaround to displaying the attribute data spatially, but I am unsure of how to do this without compromising the connection between the localities and the plans which cover them.

Re: Symbolization of Non-Null Fields within Polygon Layer

AlfredBaldenweck — Fri, 23 May 2025 20:15:22 GMT

Oof, let's try making this a bit easier for you.

We're going to use attribute-driven symbology to make this work.

Symbolize by single symbol
Go to edit that symbol
Hit the hamburger menu in the upper right of the Symbology Pane and turn on the "Allow SYmbol Property connections"
There will now be little GDB icons next to different things in your symbol layer properties
Go to the wrench tab and add a new marker symbol
Switch back to the layers tab and change the symbol to an appropriate one. I chose a motorcycle for the bike field, for example
Next to the "Size" parameter, hit the GDB icon
Hit the Green X button
Input the following code (change the field to match your field names)

if ($feature.Bike_Plans== null){ return 0 }

Note: You can also try if(!IsEmpty($feature.Bike_Plans))... instead.

Hit OK and OK Again
Apply your symbology

So, what we did was say "If this field is empty, make the symbol size 0". When the field is not empty, it will match whatever size you normally have in the size field.

Taking this, we can go back to the wrench tab and duplicate this symbol layer

and change the symbol and the field we're checking each time.

And then we get this as the output

Be careful if doing random points to change the seed value each time, and change the spacing in general, or else they all end up on top of each other.

Now.

This is going to look awful in your legend.

There are other ways to do this, but I'd suggest making a dummy point feature class with a name field and 5 points.

Update the name field so each point matches your symbol classes
And change the heading to say like "Planned Use"
Now, duplicate the polygon layer and turn off all the points
In your Layout, change your legend's properties so that the "Layer visibility" box is unchecked
Turn off or remove the layer with the symbology from your legend
You now have an OK-looking legend.

Hope this helps!

Re: Symbolization of Non-Null Fields within Polygon Layer

OliverEmily — Fri, 23 May 2025 20:19:14 GMT

This is amazing! Thank you so much for working through my chaos haha, I figured I was making this a bit too difficult for myself.

Re: Symbolization of Non-Null Fields within Polygon Layer

AlfredBaldenweck — Fri, 23 May 2025 20:25:25 GMT

It's one of my favorite capabilities in Pro. You can do a lot of cool stuff with it.