Ok, I've learned a little more. When you re-enable auto updates, ListCollectionView.handlePendingUpdates() is called. This function optimizes row-update operations, combining them into a single event, but row-add operations get handled one by one. So the adds are no more efficient with auto-updates disabled than enabled.
Is there any way to refresh the entire list, and prevent the update queue from being flushed? I tried calling refresh() before enableAutoUpdates(), but it actually prevents the update from happening at all. Rows only get added in the visible area -- no scrollbar is created until I collapse and expand the parent node. --- In flexcoders@yahoogroups.com, "whatabrain" <[EMAIL PROTECTED]> wrote: > > Sorry for cluttering the group... > > I found one more detail. If, instead of disabling auto-update on the > root node, I do it on the first (and currently only) child node: > > gridData[0].children.disableAutoUpdate(); > > and don't re-enable updates, rows still get added, but only up to the > limit of the AdvancedDataGrid's current scroll area. If I then > collapse and expand the root, I see all the rows. > > If I do enable auto-update later on the child, the rows get drawn, > but it takes even longer than without this trick (14 seconds instead > of 8). > > > > --- In flexcoders@yahoogroups.com, "whatabrain" <junk1@> wrote: > > > > Huh. I just noticed that when I comment out the line that calls > > enableAutoUpdate(), auto-update still happens. This tells me I'm > > doing something wrong. Any ideas? > > > > > > > > --- In flexcoders@yahoogroups.com, "whatabrain" <junk1@> wrote: > > > > > > Replacing the dataProvider isn't the best option for my > particular > > > application, since requests to add rows will come in at random > > > intervals, and I don't want to lose selection state and such. > > > > > > So I've written the code such that, if two add requests happen > > within > > > 300ms of each other, I call disableAutoUpdate. If, after that, > > 500ms > > > go by with no add requests, I call enableAutoUpdate(). > > > > > > But now, adding 1000 rows takes just as long as before. With the > > tree > > > collapsed (or with a regular DataGrid), it takes 1 second. With > the > > > tree opened, it takes 8, with or without auto-update. > > > > > > Any idea why this might be? I can switch to replacing the > > > dataProvider and only running this optimization when the app > first > > > loads, but I'd rather not. > > > > > > More information: The dataProvider is a subclass of > > ArrayCollection, > > > which contains objects with a "children" member, which is another > > > ArrayCollection. > > > > > > > > > private var m_lastAdd:Number = 0; > > > private var m_autoUpdateEnabled:Boolean = true; > > > > > > // This is called 1000 times > > > private function AddItem(name:String):void > > > { > > > var now:Number = (new Date()).getTime(); > > > if (m_autoUpdateEnabled && (now - m_lastAdd < 300)) > > > { > > > gridData.disableAutoUpdate(); > > > m_autoUpdateEnabled = false; > > > setTimeout(flushAddQueue, 500); > > > } > > > m_lastAdd = now; > > > [Then call the add function, which puts items into the 0th group] > > > } > > > > > > private function flushAddQueue():void > > > { > > > if (!m_autoUpdateEnabled && ((new Date()).getTime() - m_lastAdd < > > > 300)) > > > { > > > gridData.enableAutoUpdate(); > > > m_autoUpdateEnabled = true; > > > } > > > else > > > setTimeout(flushAddQueue, 500); > > > } > > > > > > > > > > > > Thanks for all your help so far! > > > > > > > > > --- In flexcoders@yahoogroups.com, "Daniel Gold" <danielggold@> > > > wrote: > > > > > > > > I've seen a lot of posts with performance related to using > > Bindable > > > > Collections like that. One of the dangerous of having such a > > useful > > > easy API > > > > for updating controls... > > > > > > > > Just to expand on what Alex is suggesting, suppose your service > > > call returns > > > > to a function called updateData, and your control is bound to a > > > _data > > > > ArrayCollection > > > > > > > > public function updateData(newData:IList):void > > > > { > > > > var newData:Array =[]; > > > > for each(var data:Object in IList) > > > > { > > > > _newData.push(data); > > > > } > > > > _data.source = newData; > > > > _data.refresh(); > > > > } > > > > > > > > That's an extremely basic code example, and actually > unnecessary > > to > > > loop > > > > like that in most cases, but basic principle is get your data > > > structured in > > > > an Array or similar structure, add new items, remove old > > > unnecessary items, > > > > whatever you need to do, concat or replace the source Array of > > your > > > > ArrayCollection, and then call refresh which will dispatch a > > > > COLLECTION_CHANGE event which will trigger any controls using > it > > as > > > a > > > > dataProvider to update. > > > > > > > > On Thu, Jul 31, 2008 at 6:47 PM, Alex Harui <aharui@> wrote: > > > > > > > > > There is enable/disableAutoUpdate, but adding rows one at > a > > > time is > > > > > inefficient. Just concat the two arrays and replace the > > > dataprovider > > > > > > > > > > > > > > > ------------------------------ > > > > > > > > > > *From:* flexcoders@yahoogroups.com > > > [mailto:[EMAIL PROTECTED] *On > > > > > Behalf Of *whatabrain > > > > > *Sent:* Thursday, July 31, 2008 3:23 PM > > > > > *To:* flexcoders@yahoogroups.com > > > > > *Subject:* [flexcoders] How to temporarily stop a > dataProvider > > > from > > > > > updating UI > > > > > > > > > > > > > > > > > > > > I've found that adding a lot of rows (1000+) to an > > > AdvancedDataGrid can > > > > > be quite slow, if the rows happen to be visible (in an open > > node > > > of the > > > > > tree). I don't know why this is the case, especially since > it's > > > not the > > > > > case in a regular DataGrid, but I'd like to work around it. > > > > > > > > > > So how can I tell the AdvancedDataGrid to temporarily ignore > > > updates to > > > > > the dataProvider? Once the large number of rows have been > > added, > > > I'll > > > > > turn the automatic updating back on, for the slow trickle of > > > updates > > > > > that come after that. > > > > > > > > > > > > > > > > > > > > > > > > >