Service Not Drawing in WAB 2.17

[jfischer91]

Yes, I know WAB is going away. Yes, I'm redeveloping in ExpB. No, I haven't deployed yet and am stuck with WAB for now. Yes, I know WAB Dev Edition 2.17 is old but I'm not looking to update it, just trying to hold on until I can deploy in ExpB.

One layer coming from an ArcGIS Server 10.9.1 is not drawing in the app. It will not show the legend in the Layer List widget. Clicking "Description" at the layer level returns a 500 error, but clicking it at the service level does take me to the REST endpoint. I can query the REST service with the same parameters in the request from the app and data returns successfully, so it seems like a problem with the app. I've overwritten the service with no luck.

 

I don't know how long this has been the case; I found out yesterday. I haven't made any changes to the app in several months.

[BrianLeroux]

Looking at your web debugger and comparing the url to your manual rest query, they are different. The URL shows layer=show:-1, different bounding box, and different output size. I think the show:-1 means to hide all layers. So you would have to figure out why that is set to hide all layers. To check if that is the case though you can take the url from web debugger and put it into a browser window and tweak that parameter to see if you can get it working.

[jfischer91]

Hi Brian,

Thanks for the response, and thanks for catching those differences! The "layers=show:-1" seems to be the issue here. I copied that request and pasted in a browser, changed the -1 to 0 and it returned an image of the layer just fine. The problem now is, I have no idea why that parameter gets set on the requests for that layer in the app. It doesn't seem to be set for any other layers. I've looked at the configs for the Layer List widget and the app itself and don't see any way to specify that specifically. It's also strange that I still get a 500 error when trying to go to the REST page for the layer of that service.

[BrianLeroux]

Sounds like we are on the right track. I assume that layer is loaded in WAB because the WAB app is linked to a web map. I would check the layer settings in the web map itself. If nothing is glaringly obvious there, I like to use AGO Assistant to manually look at the json config of the layer in the web map. https://ago-assistant.esri.com/

[jfischer91 · Accepted solution]

The WAB app is linked to a web map. Interestingly, that layer wouldn't draw within the web map when I opened it. I checked the web map json and didn't find anything that seemed off, but I also didn't see anything that looked like it controlled the layer's drawing, other than just on/off. 

I ended up just removing the layer from the web map and adding it back in, and that seems to have fixed it. The app has 2 layer lists (one showing agency layers, the other showing collaborator layers), and now that layer is showing in both of them, whereas it used to only show in one, and I can't figure out how to change that, but the solution is sufficient for my immediate needs.

Thanks for reaching out @BrianLeroux!