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AW.UI.Grid Virtual Rendering Buffer

I swear I've read about this before but I can't find it now in the forum.

Is there a way to set a "buffer" when the grid is in virtual mode so that it renders X number of rows above and below the viewable area in order to facilitate scolling without having the grid go blank?

I am almost positive this was posted in the forum, but the support forum is difficult to sort through because the search function is not very powerful. I spent about an hour trying to find it and gave up.
Tuesday, March 14, 2006
AW paints 20 rows below and above visible area. This happens in the background, so when scrolling slowly you should never see blank rows.

In 2.0 this parameter is hardcoded into /source/lib/grid/virtual.js
Alex (ActiveWidgets)
Tuesday, March 14, 2006
Are you referring to this spot?
var x1 = Math.min(count, Math.max(0, top - 20));
var x2 = Math.min(count, top);
var x3 = Math.min(count, top + client);
var x4 = Math.min(count, top + client + 20);

Hrm, I was hoping it was controlled someplace else because that was the first place I looked in the code and I have already tried changing that but it seemingly has no effect, if I scroll quickly, even just a short distance the values in the newly visible rows take a few seconds to show up. This is most easily demonstrated with a grid which only contains 30 rows with 20 of them being visible. You should be able to scroll all the way to the end without it going blank but it always takes a second or two for the values to appear.
Tuesday, March 14, 2006
Actually, I think that does work, its just that for some reason the javascript runs really slow in IE... with FF it has a noticable effect if I double it to 40 I can jump a couple screens at a time with no blanking as long as I pause a little here and there to let the rendering catch up.
Tuesday, March 14, 2006

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