It’s a little difficult to tell what you are doing so I’m not sure I fully understand how you have this configured and why you have these lambdas. Were I to build something like this I’d have the UI interacting with OH through the REST API, the “configuration” represented via Items, and Rules that trigger when the configuration to update other Items as necessary so represent the updated configuration. the Rules that care about the configuration then just check the relevant config Items and do the appropriate thing based on those instead of calling a lambda to recalculate the config to see what they need to do.
I don’t see the purpose for the lambdas, but I’m also not seeing your code.
If you want to get deeper into the language look at:
- Textual Rules | openHAB
- Xtend - Expressions
- Design Pattern: Working with Groups in Rules
- use VSCode with the openHAB extension
- remember that the Classes you are working with are ultimately Java Classes, the JavaDoc are here: Archived Projects | The Eclipse Foundation
- remember you have access to all of the standard Java libraries: Java Platform SE 8
- remember that DateTime (e.g.
now) is represented using the Joda library: DateTime (Joda time 2.2 API)
I don’t think Xtend is incapable of supporting your overall goal of having your own UI. But you may need to rethink how this UI integrates with an interacts with OH.