Be clear with categorical navigation, and expose the items (‘children’) that are being modified.
One issue that seems unclear is that there can be n items under each category, but it’s hidden in a dropdown, so I have to remember:
- how many items there are
- which have been modified
- how far along am I in my work for the category
What ends up happening is I’m potentially modifying n items within a category, and traversing and saving across multiple categories. Flatten the child items.
Build on common navigation patterns for this step through
Since you potential navigate two dimensions, take advantage of global vs contextual nav patterns common to many websites.
By exposing the items as children of the category, you can:
- show them how many
- indicate when an items configuration has been modified
- indicate the current item they are editing
Try being explicit with the Next button. Indicate it will save the categories’ items, and move them forward.
By keeping the items exposed, and using change indicators (see mock), you’ll reveal which items are modified. Then, when you either Save & Exit > or Save & Continue > the whole batch is saved.
If need be, you can prompt a progress indicator which says which items are processing. It’s intentional extra friction, but a tradeoff for clarity if you have high cardinality at the item level. I don’t know your use case, so it might not apply.