I have a Dialog with a sub component (A vertical layout) that is being replaced asynchronously. There is an indeterminate Progress Bar on the dialog as well. The async call executes fine, and calls ui.access to replace the component. However when that update is being pushed to the UI, the progress bar stops animating for 1-2 seconds, I assume as the UI update is actually applied to the Dialog? Is this expected? It seems to defeat the purpose of an indeterminate progress bar if it locks up during the UI update that it’s supposed to be waiting for.
The action that causes the update can be triggered repeatedly, so I can report that this happens on every async update to that dialog. The progress bar is left visible at all times.
I should note that this UI update might be more significant than most. It’s a layout with a couple grids with multiple columns so maybe ~100 components total. Though I was hoping that the UI would understand that the progress bar should continue animating until it’s actually told to stop.
Edit: I’ve confirmed a couple things…
I replaced the Vaadin progress bar with a pure CSS progress bar i.e. animated purely using CSS @keyframes, and even this implementation freezes when the UI is being updated. This tells me that the browser is apparently freezing all animation during the layout update, and thus this may not be a framework issue.
I also confirmed that freeze doesn’t appear to happen (or at least isn’t visible) when the update is a simpler layout, e.g. a VerticalLayout with a span inside it. So something about the more complex updates is causing the browser to cease animations. Not sure if that’s anything Vaadin can control or account for, but I’ll keep pluggin.