The function you specify with dataTipFunction attribute must accept an Object (typically a data row) and return a String (for the toolTip). This implies that the work must be performed within the confines of a single function.
But what if you want to make a RO call to the server and fetch the latest tooltip content from the server - right at the mouse over event?
That normally involves two functions: one to make the call and another to process the result event. Can't fit those two inside a simple function now, can I?
If my desired outcome is actually possible, can someone provide a bare conceptual layout of such an entity would be constructed?
Looks like this was asked back in Oct of 2009 (2308854) - and never answered. That's not good...
My current workaround is to use a MXDataGridItemRenderer and do the toolTip / RO call inside that.
But I can't seem to get the "fresher" tip content to overwrite the previous tip value displayed.