I figured it out. The problem was due to the fact that I had a bind tag set on the ArrayCollection getter that is updated whenever a CollectionChange occurs.
I will post a more complete question next time. Thanks to Tim and Tracy for trying to help. <?xml version="1.0" encoding="utf-8"?> <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"; layout="absolute" applicationComplete="init()"> <mx:Label id="label1" text="{albumsThumbnailList.selectedIndex}" x="10" y="12"/> <mx:Label id="label2" text="{presentedAlbumIndex}" x="10" y="38"/> <mx:TileList id="albumsThumbnailList" direction="vertical" dataProvider="{presentedAlbums}" selectedIndex="{presentedAlbumIndex}" x="160" y="10" change="presentedAlbumIndex=albumsThumbnailList.selectedIndex" height="400"/> <mx:Button click="test()" x="29" y="136"/> <mx:Script> <![CDATA[ import mx.events.CollectionEvent; import mx.collections.ArrayCollection; private var _includedAlbums:ArrayCollection = new ArrayCollection(["zero","one","two","three","four","five","six","seven"]\ ); [Bindable] private var presentedAlbumIndex:int = -1; private function init():void { _includedAlbums.addEventListener(CollectionEvent.COLLECTION_CHANGE, function():void { dispatchEvent(new Event("albumDataChanged")); } ); } private function test():void { _includedAlbums.removeItemAt(1); presentedAlbumIndex--; } [Bindable(event="albumDataChanged")] private function get presentedAlbums():ArrayCollection { return _includedAlbums; } ]]> </mx:Script> </mx:Application> --- In [email protected], "steve horvath" <flexcod...@...> wrote: > > My apologies. I really didn't mean to come across as brash. I realize you are trying to help and I do appreciate it. > > Let me put together a small app and I'll post it here. > > Steve > > --- In [email protected], "Tim Hoff" TimHoff@ wrote: > > > > > > Yes, _includedAlbums.selectedItem should have been > > albumsThumbnailList.selectedItem. And no, the code below is not > > sufficient to reproduce the problem. For instance, where is > > presentations.currentPresentation.presentedAlbumIndex defined? If you > > want someone's help here, make it easy for them to copy and paste a > > small Application for testing. > > > > Besides that, excuse the hell out of me. Go ahead and continue to look > > at it for hours. > > > > -TH > > > > --- In [email protected], "steve horvath" <flexcoders@> > > wrote: > > > > > > > > > The code below is sufficient to reproduce the problem. > > > > > > _includedAlbums is an ArrayCollection, so no .selectedItem property on > > > that. In any case, I am already happily setting the > > presentedAlbumIndex > > > by other means. It's the TileList selectedIndex that I need to update > > > properly. > > > > > > --- In [email protected], "Tim Hoff" TimHoff@ wrote: > > > > > > > > > > > > Not sure what to tell you without having a sample application to > > play > > > > with. But, you could try some brute force techniques, like: > > > > > > > > _includedAlbums.removeItemAt(1); > > > > presentations.currentPresentation.presentedAlbumIndex = > > > > _includedAlbums.getItemIndex(_includedAlbums.selectedItem); > > > > > > > > -TH > > > > > > > > --- In [email protected], "steve horvath" flexcoders@ > > > > wrote: > > > > > > > > > > > > > > > I've been looking at this for hours. Does anyone know why I am > > > seeing > > > > > this behavior? Or at least tell me how I can debug to provide more > > > > > information. > > > > > > > > > > > > > > > --- In [email protected], "steve horvath" flexcoders@ > > > > > wrote: > > > > > > > > > > > > > > > > > > I have a TileList: > > > > > > > > > > > > <mx:Label id="label1" text="{albumsThumbnailList.selectedIndex}" > > > /> > > > > > > <mx:Label id="label2" > > > > > > text="{presentations.currentPresentation.presentedAlbumIndex}" > > /> > > > > > > <mx:TileList id="albumsThumbnailList" backgroundAlpha="0" > > > > > > useRollOver="false" initialize="mySizeBinding(event);" > > > > > > > > > > > dataProvider="{presentations.currentPresentation.presentedAlbums}" > > > > > > itemRenderer="PresentationAlbumRenderer" > > > > > > > > > > > > > > > > > > > > > > > > > > selectedIndex="{presentations.currentPresentation.presentedAlbumIndex}" > > > > > > change="albumChangeHandler()" /> > > > > > > > > > > > > public function test():void { > > > > > > _includedAlbums.removeItemAt(1); > > > > > > dispatchEvent(new Event("albumToggledEvent")); > > > > > > presentedAlbumIndex--; > > > > > > } > > > > > > > > > > > > BEFORE test(): > > > > > > label1 == 5 > > > > > > label2 == 5 > > > > > > > > > > > > AFTER test(): > > > > > > label1 == 5 > > > > > > label2 == 4 > > > > > > > > > > > > Problem is, when the 5th index is currently selected and I > > delete > > > an > > > > > > item earlier in the list (like index 2), the data provider > > updates > > > > the > > > > > > list. But the selectedIndex doesn't get updated. (See test() > > > > > > function.) I noticed when I comment out the removeItemAt line, > > the > > > > > > index gets updated just fine. > > > > > > > > > > > > How do I update the data provider and index in the same > > operation > > > > and > > > > > > get the TileList to bind correctly? Can I perhaps subclass > > > TileList > > > > > and > > > > > > override a function? Some other way? > > > > > > > > > > > > I tried looking into the internals of ListBase, inspecting > > > > > > selectedIndex, and generally browsing around at runtime. I > > noticed > > > > > that > > > > > > selectedIndex does get set to 4 momentarily. Then it gets set > > > right > > > > > > back to 5 again. I'm guessing it may have to do with the > > > > > > updateDisplayList or something like that. > > > > > > > > > > > > > > > > > > > > >
