We have 130 + image services in a web app and want to publish and customize using Developer Edition of WAB.
The idea is to organize and group image services into a custom layer tree so that users can expand and collapse sublayers, similar to publishing an MXD with a built in tree.
Is it possible to complete this task? We found the object that is loaded to a LayerListView. I believe we want to replicate the object into subgroups with only (a,b,c) layers in object 1, (d,e,f) layers in object 2, (g,h,i) layers in object 3 and then load those 3 separate objects in their own LayerListView within separate DIV elements in the LayerList widget.