When a binding subscribes to a tag, it hands the tag provider a tag change listener. That is the real consumer. Your shim must save that in a final field when creating the intermediate tag change listener your shim will hand to the real tag provider. Your shim's intermediate listener objects must be 1:1 with real consumers, and you will have to keep track of them in the shim for later unsubscription. The shim's intermediate listener must have a non-final field to hold the most recent real-time QV. And then whatever else you need for your simulation.
How do I access a tag change listener that has been created and attached to the binding outside of my code? I already keep track of the most recent QV in my wrapper. I think the only piece I am missing is the real consumer tag change listener. I am also already keeping track of intermediate listeners, as I struggled with leaking listeners in early testing.
After you've replaced the tag provider, all future tag subscriptions will be routed to your provider shim. Create the intermediate subscription objects then, unconditionally.
You cannot obtain those listeners any other way. (You have to handle all subscriptions for the provider you are intercepting, whether you plan to simulate them or not.)
THIS is why I am required to refresh the binding, because the subscription for the binding is created before my shim provider has been created. I can intercept subscriptions just fine, it is the overriding of the existing subscription (between the real consumer and the default tag provider) that is the problem.
When are you installing your shim? (It should be in your ClientHook.startup() method. Or perhaps in the constructor.)
Ahhh.... that might be the issue. I have been instantiating the shim in the startup method of my custom vision component. I will attempt and report.
That did the trick for a true client session. Now I just need to be able to pass the client context to the designer session so developers can test before deployment. Thank you for all your help!!