It is possible that at present it is not possible to do something like the following?
Essentially I want to keep adding to a text variable… This step is triggered through an event of a custom widget. When I add a message action before or after the store command, the messages are firing as expected. When I just write a single string to the target variable that text is shown…
Only if I want to keep adding to the same variable (i.e. overwrite its old state) in a single step via an expression nothing happens. The resulting variable will just stay empty.
Use-case: I want to give the operator a better visual indication that something is still happening which the custom widget loops through several records. Each loop is triggering table actions which cause a processing delay. If I update the state variable directly from within the custom widget it is immediately filled with the entire loop as the custom widget event firing mechanism at present will not wait for the last event to be processed. Instead, it just fires all event in succession and the processing is then queued as part of the event queue - so it seems… To work around this behavior, I reverted to the presented alternative route.
In theory this should allow me to update the state in sync with what is actually happening in the background with the table triggers… but, well… it doesn’t unfortunately as explained.
… ok… so this actually works 
