What is your use case? I presume not just displaying a spinning circle on each Grid row, though you can do that with ImageRenderer. Are there some rows that have a defined progress and some rows where it’s indeterminate?
It is some kind of fallback, that would show just a spinning circle, if there is no progress data available. So basically the same use case as for the indeterminate mode of ProgressBar.
Ah, all right. Currently ProgressBarRenderer defaults to displaying a disabled progress bar on null data. However, you could fairly easily customize the widgetset, adding your own implementation of
com.vaadin.client.renderers.ProgressBarRenderer - you’d only need to replace the setEnabled calls with appropriate setIndeterminate calls.