How do I create a Custom Layer in 4.0?

Question

I see that MapImageLayer has replaced ArcGISDynamicMapServiceLayer in 4.0 and that DynamicMapServiceLayer is under consideration.

In 3.x, I created a custom layer from a netCDF hosted on a Unitdata THREDDS  Server using it's WMS capabilities. I had to create a custom layer and not use the WMS Layer class because the layer had extra properties like color, number of bands, etc.

With MapImageLayer in 4.0, is there a way to create a custom layer like there was with DynamicMapServiceLayer?

I see that the class still has getImageUrl which helped me use the extra properties.

I used the Custom Tiled Layer Type page to help me create the layer:

https://developers.arcgis.com/javascript/3/jssamples/layers_custom_tiled.html

KristianEkenes · Accepted Answer

The line saying that "DynamicMapServiceLayer is under consideration" is incorrect. This layer type will not be implemented in our 4.x series. We'll update that page to avoid confusion.

Regarding the creation of custom layers - our layers API isn't finished yet. We just released the basics of our common layers for 4.0. We will document how to create custom layers in a future release (hopefully 4.1) when the layers API is more mature.