topic Re: Snapping Not Engaging in ArcMap in ArcGIS Mapping and Charting Questions

Snapping Not Engaging in ArcMap

Tim_Ultee — Tue, 24 Jul 2018 15:30:59 GMT

I'm using ArcMap 10.5.1 and have been having issues with snapping not engaging for some time. I will have snapping engaged in an edit session and try to use it with the measure or create feature tool, but snapping won't engage. When I move the mouse to try to engage it, it switches to the hourglass for a moment before continuing not to snap.

I've tried modifying the snapping tolerance and the snapping types (edge, vertex, etc.) to no avail. Sometimes zooming in or out will suddenly allow snapping to work, but when I pan/zoom again it won't work. The only solution I've found to this so far is to reduce the number of layers displayed (turning off the basemap layers group, topographic lines, etc.), but I'm working with a map now that I can't get to work even after turning off all unused layers. This map does use two point feature classes with multiple tables joined to them. I assume the main issue is that the snapping function is being overloaded, but I just finished another map using the same layers without snapping issues even without turning off extra basemap layers.

Does anyone else experience this issue, and has anyone identified the cause of the problem or a solution? Thanks.

Re: Snapping Not Engaging in ArcMap

Anonymous User — Tue, 24 Jul 2018 17:09:28 GMT

Hi Tim,

Most likely the issue is because the shapefile does not have a spatial index. I have outline the steps you can try to fix this issue.

1: In Arc Catalog go to your shape file
2: Right click>Properties
3: Indexes tab
4: In Indexes tab click 'Add'

I have also attached additional resources for you.

How to get to Spatial Index:
http://desktop.arcgis.com/en/arcmap/latest/manage-data/shapefiles/modifying-indexes-in-shapefiles-by-adding-a-spatial-index.htm

Steps to adding Spatial Index and Information on the issue:
https://support.esri.com/en/technical-article/000015316

Let me know if this works for you.

Best,

Luba

Re: Snapping Not Engaging in ArcMap

Tim_Ultee — Tue, 24 Jul 2018 17:44:40 GMT

Thanks for your reply Luba. In my case we use file geodatabase feature classes for everything. Based on reading the ArcMap Overview of Spatial Indexes page and looking in the feature class properties, I believe spatial indexes for feature classes are created and updated automatically. Please let me know if this is incorrect.

For the map in question, I found that turning off the layers with table joins allowed snapping to function normally. Removing the joins also re-enabled snapping. Is it possible that snapping fails when a visible feature class has an active join? This is frustrating in this case since these joined features are what I wanted to snap & measure, but knowing this could help me avoid the problem in the future. Though as stated in my original post, I've also experienced this issue in the past with non-joined feature classes and had to resolve it by turning off most of the mxd layers.

Re: Snapping Not Engaging in ArcMap

MichaelVolz — Tue, 24 Jul 2018 18:02:01 GMT

Have you tried importing this mxd into Pro and using Pro to perform the edits to see if you get better performance in that environment?

Are the file gdbs stored locally on your computer or on the network?

Re: Snapping Not Engaging in ArcMap

Tim_Ultee — Tue, 24 Jul 2018 18:52:50 GMT

Thanks for the suggestion Michael. Testing in Pro just now, snapping with the measure tool took a few seconds to engage for most of the features but it did work. I was hoping to identify a fix in ArcMap though since we haven't switched over to Pro yet. We're hoping to switch over to Pro soon but still have some workflow and learning-curve obstacles before then.

The file geodatabases are stored on a server but I'm hoping this isn't much of an issue since the server is in the same office I am. I don't tend to have connection issues using it for all my other GIS work.

Re: Snapping Not Engaging in ArcMap

Robert_LeClair — Wed, 25 Jul 2018 21:30:20 GMT

Another option is to enable Classic Snapping in ArcMap and set the specific layer to snap to with the snap agent you wish to use. It could be an overload as you described.

Re: Snapping Not Engaging in ArcMap

Tim_Ultee — Thu, 26 Jul 2018 18:41:47 GMT

Thanks for the suggestion Robert. In this particular case I was trying to snap with the measure tool which can't be used with classic snapping, but this is still a good strategy to keep in mind for when this happens again. I tested it and classic snapping does indeed work on this map for operations like creating a new feature.

I guess overall I'm going to assume that this is a case of ArcMap snapping being overloaded by my feature class being joined to 2-3 csv tables (the joined tables are also referenced for symbology and labeling). In the future it might be a good idea for me to export these layers as a shapefile or feature class to improve performance.

Thanks for all your suggestions!