topic Re: Basemap Load Failure in ArcGIS JavaScript Maps SDK Questions

Basemap Load Failure

MichaelWen_Timmons — Fri, 14 Apr 2023 15:08:53 GMT

I saw a few, similar threads from a few years back that went unanswered so want to see if there's a solution now.

https://community.esri.com/t5/arcgis-javascript-maps-sdk-questions/empty-basemap-not-working/m-p/619871#M57902

I am trying to capture when a mapview's default basemap fails to load. If that happens I want to switch to a backup. Right now if the default basemap is down the whole application crashes.

I tried this but nothing is caught. In fact the 'when' never got run when the first basemap fails to load.

this.view.when( ).catch()

This does not work for basemaps.

this.view.on("layerview-create-error", function(event) {

console.error("LayerView failed to create for layer with the id: ", event.layer.id);

});

Is there anything else that I can try?

Re: Basemap Load Failure

ReneRubalcava — Fri, 14 Apr 2023 15:54:05 GMT

The Basemap, and other layers, have a load props you can check.

https://developers.arcgis.com/javascript/latest/api-reference/esri-Basemap.html#loadError

https://developers.arcgis.com/javascript/latest/api-reference/esri-Basemap.html#loadStatus

https://developers.arcgis.com/javascript/latest/api-reference/esri-Basemap.html#loadWarnings

You could do something like this.

view.when(() => { console.log("Check basemap error status", view.map.basemap.loadError) });

Re: Basemap Load Failure

MichaelWen_Timmons — Fri, 14 Apr 2023 16:23:45 GMT

I don't think this would work because view.when(() would not even fire if the basemap layer fails to load.

Re: Basemap Load Failure

ReneRubalcava — Fri, 14 Apr 2023 17:48:04 GMT

You can use reactiveUtils to watch those properties. I don't really have a way to check a bad basemap, but that would be the next step to try.

https://developers.arcgis.com/javascript/latest/api-reference/esri-core-reactiveUtils.html

Re: Basemap Load Failure

MichaelWen_Timmons — Mon, 17 Apr 2023 14:18:40 GMT

I already tried it. That does not really resolve it for us because the application crashes if the default basemap fails to load, so we won't even get a chance to watch for the property change.

Re: Basemap Load Failure

MichaelWen_Timmons — Mon, 17 Apr 2023 16:38:20 GMT

Is there a way for me to create a 'blank' basemap that I can use as a default, and after mapView is generated, switch to the real default if that layer loaded correctly? I tried creating a default basemap by passing a '' url but that threw an error as well.

Re: Basemap Load Failure

MichaelWen_Timmons — Thu, 20 Apr 2023 13:57:48 GMT

Can someone please help? I tried using a USGS and ESRI basemap as the default but it messes up the zoom level of the mapView. I REALLY need to find a way to default to a blank basemap. I've already tried using '' as the url and TileLayer as the type, but it errors out. What is the correct way to create a BLANK basemap?