[FEATURE] Perspective - Get 'status' of property binding such as Query or Script

[pturmel]

Prior discussion:

"IsLoading" indicator

For a Perspective page- I want to put up a watermarked indicator over the entire window or just some components when a SQL query/data processing script is currently running, so that the user knows the data is still loading. I vaguely recall an “IsLoading” property on some Vision components. Is there a similar mechanism in Perspective? If not, has anyone achieved this by alternative means? Thanks