Allow UI polling even when a modal dialog is open

[Legioth]

Describe your motivation

UI polling (i.e. ui.addPollListener) is a "global" feature that isn't tied to any specific component. It should therefore not be considered to be "behind" a modality curtain.

Right now, you get an Ignored listener invocation for ui-poll event from the client side for an inert body element error with polling when a modal dialog is open.

Describe the solution you'd like

Make the framework register poll listeners with DomListenerRegistration::allowInert so that the listener keeps working regardless of modal dialogs.

Describe alternatives you've considered

An alternative would be to provide an overload of addPollListener that would let the developer choose whether to allow polls while a modal dialog is open. I don't think that's necessary since UI-level polling is anyways "global" and doesn't pass any user-controlled data to the server.

Additional context

Recent forum discussions:

• https://vaadin.com/forum/t/poll-listener-logging-ignored-listener-invocation-after-upgrading-to-v-24-6-0/168213
• https://vaadin.com/forum/t/vaadin-update-many-messages-in-logfile-ignored-listener-invocation/167993

[Legioth]

As a workaround, instead of registering the poll listener in the regular way, you can instead register it like this:

ComponentUtil.addListener(ui, PollEvent.class, event -> {
    System.out.println("Poll event: " + event);
}, DomListenerRegistration::allowInert);

[raghuG005]

I have implemented a workaround and it is working .