How can you access the layer behind a FeatureLayerDataSource

Question

I am using the DataSourceComponent to query a feature layer and it is successfully querying it and rendering my content.  However I need access additional capabilities not directly supported in Experience Builder from what I can see.  The datasource I am getting from the DataSourceComponent appears to correctly be a FeatureLayerDataSource which has an optional property of layer.  It seems by default or by my configuration somehow layer is always undefined.   Count is also undefined by default but if you set queryCount on the component to true then count is loaded as the documentation indicates.  I don't see anything similar for the layer.  I've looked at the type definition for DataSourceComponent/DataSourceComponentProps which does show a few more properties than the documentation does but nothing seems to indicate that it would cause layer to be loaded.

Hannes_Brandt · Answer

Hi,

i encountered a similar problem and looked a bit more into the default widgets from ESRI shiped with the Experience Builder.

Both of the following Widgets define a "getFeatureLayer" function using multiple methods of retrieving a FeatureLayer object from a FeatureLayerDataSource.

...\ArcGISExperienceBuilder\client\dist\widgets\common\edit\srcuntime\widget.tsx

...\ArcGISExperienceBuilder\client\dist\widgets\common	able\srcuntime\widget.tsx

As of exbVersion 1.14.0 the "getFeatureLayer" functions are not completely identical, as the one from the "table" widget also uses the createJSAPILayerByDataSource function which i found very helpful.

You may want to take a look at the various approaches and comments in ESRI's code.

Greetings

Hannes

RichardKorsós · Answer

Hi,

I have the same issue. Could you find the solution?

Maybe It can be the solution:

const layer = ds.layer || await ds.createJSAPILayerByDataSource();

Thanks

tbock · Answer

* I'm going off memory as it has been a while. But I believe the solution was the dependency attribute of the widget manifest.json<> file for the widget. If I am remembering correctly, adding that attribute with the value "jimu-arcgis" essentially causes the widget to wait to load until the ArcGIS JS SDK is loaded. At the time I didn't feel like this was documented clearly (at all?) but the example js-api-widget they provide has this dependency set<> so it made sense. If someone has a link to documentation that more clearly explains this behavior that would be helpful. I still find the documentation a bit confusing since it says "jimu-arcgis: will load the jimu-arcgis package that will load the ArcGIS Maps SDK for JavaScript.". However, the JS SDK often loads even if you don't do this. I suspect its more accurate to say that the builder will make sure the JS SDK is loaded before your widget or something along those lines.