I want to hide a certain selection of features when people first open the app, but allow them the option to turn them on if they choose to do so. I can set the filter in Map, but then users can't alter it, or I can provide a filter, but it defaults to being off. Is it possible for it to default to being on?
I believe Hosted Feature Layer Views (if your data is hosted) would be the best option for you. You can set a filter on the view, and then add the view to your map and the map to your application. The view's filter can be altered, but will be on by default.
For more information, see: Create hosted feature layer views—Portal for ArcGIS | ArcGIS Enterprise
I believe it's available starting at 10.6.0 and up, as the documentation drop-down only goes that far back.
Hopefully that works for you?
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