Display notification if loading a list page takes a long time
Description (last modified by )
The new features with parent/child columns that has been implemented in #2202, #2218 and #2234 may cause the query for loading the list to take longer time than usual. This is more likely the further apart the parent/child items are (for example, adding a biosource column to the raw bioassays table). There is a caching mechanism in place but the initial query may still take several seconds (or even a minute).
It would be nice to display some feedback to the user while the list is loading. I am thinking that this could be hooked up to the Form.submit() method which starts a timer. After about 1 second it should display a message like "Please wait... the list is loading!". If it takes less than a second the timer will of course not be triggered since the page has been replaced with the new list.