Legends for Some Layers Missing in Print

MichaelWen_Timmons

I have a JS API 4.25 app where the Editor widget is used to add features to a map, and there is a function to print the map of the current extent. I ran into an issue where the map and the features on the map  renders fine but sometimes legends for some of the layers do not show. For example, sometimes the map contains features from the Point, Polygon and Line layers but only Point and Polygon features have legends. None of the Line features show in Legends. I would pan on the map and print again, and usually all of the layers would show next time.

Could this be some kind of caching issue where the MapView is not passing all the layers to PrintParameters? Is there a way to force all of these objects to refresh before printing?

Noah Sager

Hi @MichaelWen_Timmons, thanks for posting your question here.

What I think is happening is that some layers are sent by screenshot to the print service, and others are being sent by layer. This is why you see that long image data string in the request. When layers are sent by screenshot to the print service, they do not display in the printed legend. We have this documented, along with what cases are sent via screenshot, here: https://developers.arcgis.com/javascript/latest/api-reference/esri-rest-print.html

However, if you are able to pan the map and print again, and it all prints fine that time, then there is something interesting going on. I have not encountered this before, but if you could share a simplified reproducible test app, I could take a look. If not, I would recommend checking the status of the newly added features and making sure it's loaded properly. Something like a console.log statement to see if it's loaded, and then check after panning the map again.