[Chandler-dev] Problems using notifications to improve performance

[D John Anderson]

Hi Andi:

I'm working on using notifications to eliminate redrawing.

The basic idea is to look at the change, see if it affects the  
widget, and if not, don't draw anything. Also, if it is a simple  
change, i.e. deleting or adding a item, make a small change to the  
widget instead of recreating the widget from scratch as we now do.

Considering the table. If an item is removed from the table we could  
delete that single row instead of recreating the entire table from  
scratch as I do now. However, when an op "remove" comes through or a  
"refresh" happens for an item that was deleted there is no indication  
what the item's index was. Unfortunately, this means we can't  
optimize the drawing for any item that is deleted.

I'm curious to know how hard it would be to include information about  
the location of the item being deleted. I suspect that most of these  
cases will occur in background sharing of subscribed collections.

John