Snap to ArcGISDynamicMapServiceLayer in WAB

OndrejFialík

How do I enable snapping to ArcGISDynamicMapServiceLayer in WAB.

I try

var snapManager = this.map.enableSnapping();

var layerDyn = this.map.getLayer(this.map.layerIds[1]);

var layerInfos = [  {layer: layerDyn} ];

snapManager.setLayerInfos(layerInfos);

but snapping not working.

Please help me

Thanks a lot