I'm new to InDesign and very familiar with Photoshop. I'm stumped that I can't arrange layers the way I can in Photoshop and Illustrator.
In Photoshop, the Layers window has Create New Group and Create New Layer buttons. You can drag any layer into any group (which behaves like a folder) and drop any group into another group. In Illustrator, there are Create New Sublayer and Create New Layer buttons that you can drag and drop objects between (Illustrator feels similar to Photoshop). However, in InDesign there is only a Create New Layer button. In the following InDesign Layers window, I can only drop Layer 4 between the "main" layers. For example, I can drop Layer 4 above the layer named Junk Show, but I can't drop it in the "folder" named Road Sign and I can't drop Layer 4 inside Junk Show.
Am I missing something conceptually or is this just how InDesign's layers work?
FWIW, I'm trying to organize the layers into "folders" to manage an (eventually) large book with many hundreds of images, captions, and text frames.
Couple of things: Your Layer 4 has no objects in it. Top level layers are just that in ID. You can add items to any layer and move objects between layers. The sub-layers you show are grouped items which can be opened to rearrange the items within the group or you can add new items to the group. Top layers can only go before or after other top layers.