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Re: NSTableView: tableView:objectValueForTableColumn:row called more than necessary when scrolling



It seems like you might be able to write a once-off class which acted as a simple data-source cache, keeping track of the last few requests so they can be re-provided as necessary, and then use that anywhere you needed it.


Hamish Allan wrote:
Hi Ben,

I suspect the designers of NSTableView decided to save themselves
having to cache values for the currently-selected row (which would
later be needed to redraw that row unhighlighted) and in doing so
doomed the rest of us to have to write such code in every single
datasource.

Hamish

On Jan 16, 2008 10:07 PM, Ben Chen <email@hidden> wrote:
Hi everyone,

I just found that when scrolling a NSTableView inside a NSScrollView
one row at a time, each time the tableview will not only ask the data
source for the new row's value but also ask for the last row's. So if
you scroll the table all the way donw, eventually it makes twice calls
as the number of rows in the table.

I been programming a app that performance of the table view is vital,
so I really want the table view call the data source as few as
possible. Does anyone know a solution?

Thanks,
Ben
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References: 
 >NSTableView: tableView:objectValueForTableColumn:row called more than necessary when scrolling (From: "Ben Chen" <email@hidden>)
 >Re: NSTableView: tableView:objectValueForTableColumn:row called more than necessary when scrolling (From: "Hamish Allan" <email@hidden>)



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