Using FeatureCollection with EsriJS 4
Rene Rubalcava | May 29, 2016
When working with FeatureLayers, sometimes you don't want to work directly with a FeatureService, but simply work with graphics and take advantage of characteristics of a FeatureLayer like the renderer.
This is simple enough to do using the source property of a FeatureLayer to update the graphics. You can even update the source during runtime to update your data as needed.