topic Re: How to get selected feature(s) from selection tool? in ArcGIS Pro SDK Questions

How to get selected feature(s) from selection tool?

OscarYam — Tue, 11 Oct 2022 10:35:31 GMT

I would like to create a button that updates the selected feature's attribute. When I started coding, I found that I cannot get the selected feature after I use the default selection tool(the tools under esri_mapping_selectToolPalette). Is it any method to get the selected feature from the default selection tool?

Re: How to get selected feature(s) from selection tool?

CharlesMacleod — Tue, 11 Oct 2022 21:23:11 GMT

Subscribe to the MapSelectionChangedEvent. Any changes to the map selection via selection tool, via custom selection, etc. will fire the event.

ArcGIS.Desktop.Mapping.Events.MapSelectionChangedEvent.Subscribe((args) => { //If u are only interested in one particular map... if (args.Map.Name == "The Map Name I am Interested In") { System.Diagnostics.Debug.WriteLine("Selection changed"); var sel = args.Selection;//This is what is selected if (sel.Count == 0) { System.Diagnostics.Debug.WriteLine(" 0 features selected"); return; } //enumerate current selection - a series of keyvalue pairs //key is the MapMember, Value is the list of OIDs foreach(var kvp in sel.ToDictionary()) { var oids = kvp.Value; //OIDs of the selected features var oid_str_list = oids.Select(oid => oid.ToString()).ToList(); var oid_str = string.Join(",", oid_str_list); System.Diagnostics.Debug.WriteLine( $"{kvp.Key.Name}: {oid_str}"); if (kvp.Key is BasicFeatureLayer fl) { //TODO selection is on a vector layer... } else if (kvp.Key is StandaloneTable tbl) { //TODO selection is on a table... } //else if (....) //{ // etc,etc. //} } } });

Note: In 2.x, the event argument syntax is slightly different. The Selection property is a Dictionary so there is no sel.ToDictionary() as such.

Re: How to get selected feature(s) from selection tool?

OscarYam — Thu, 27 Oct 2022 07:06:49 GMT

Would you mind explaining more about where should these codes go to? Should those codes go to Module1.cs or the button.cs? I am using Arcgis pro 3.0.

Re: How to get selected feature(s) from selection tool?

CharlesMacleod — Thu, 27 Oct 2022 18:58:33 GMT

The Module is probably the best place. There is an initialize method in the Module which is probably a good spot. I would also set your module autoLoad attribute to true in the Config.daml.

internal class Module1 : Module { private static Module1 _this = null; ... protected override bool Initialize() { //TODO subscribe to the mapping event here return true; }

Re: How to get selected feature(s) from selection tool?

OscarYam — Fri, 28 Oct 2022 03:31:16 GMT

Thank you for your solution. Here is what I come up with to fit my situation.

I added the following code in module1.cs like you said. And created a class to store selections so I can access the selected features within my addin project.

protected override bool Initialize() { SubscribleMapSelectionChangedEvent(); return base.Initialize(); } private void SubscribleMapSelectionChangedEvent() { ArcGIS.Desktop.Mapping.Events.MapSelectionChangedEvent.Subscribe((args) => { //If u are only interested in one particular map... if (args.Map.Name == "My map") { #if DEBUG System.Diagnostics.Debug.WriteLine("Selection changed"); #endif var sel = args.Selection;//This is what is selected if (sel.Count == 0) { #if DEBUG System.Diagnostics.Debug.WriteLine(" 0 features selected"); #endif return; } else { CommonObject.GlobalVariables.SelectedFeatures = sel.ToDictionary(); } } }); }

Re: How to get selected feature(s) from selection tool?

CharlesMacleod — Fri, 28 Oct 2022 05:32:42 GMT

Nice work Oscar. One thing I thought I would mention: The module class is actually already global throughout the addin (by design). All classes can access it via the special "singleton" property called "Current".

Therefore, if you wanted, you could add a "SelectedFeatures" property to your module class directly and access it that way. So it could look something like this:

internal class Module1 : Module { ... private Dictionary<MapMember, List<long>> _selFeatures; //Any (non-private) module property or method can be accessed from //anywhere within the addin internal Dictionary<MapMember, List<long>> SelectedFeatures => _selFeatures ??= new Dictionary<MapMember, List<long>>(); //elsewhere...access the property via Module1.Current... foreach(var kvp in Module1.Current.SelectedFeatures) {

Re: How to get selected feature(s) from selection tool?

OscarYam — Mon, 31 Oct 2022 04:35:42 GMT

Thanks for your additional info, cheers!