Hah, Tim, your spell didn't quite do it, huh? ;) Container-based renderers are problematic. For anything even slightly complex, extend UIComponent.
I copy ListItemRenderer, it is a great starting point. It is pretty easy to see where to add your special incantations. Tracy Spratt, Lariat Services, development services available _____ From: flexcoders@yahoogroups.com [mailto:flexcod...@yahoogroups.com] On Behalf Of Tim Hoff Sent: Saturday, April 18, 2009 5:27 PM To: flexcoders@yahoogroups.com Subject: [flexcoders] Re: Custom List ItemRenderer / Recycling troubles (height incorrect) Hi, Yes, after playing with it a little, you're correct; my suggestion only works in AS. Sorry, I always extend UIComponent for itemRenderers that need to have a variableRowHeight. BTW, in the future, please sign your posts; so that we can put a name to your warm and positive comments. -TH --- In flexcod...@yahoogro <mailto:flexcoders%40yahoogroups.com> ups.com, "wubac1" <wub...@...> wrote: > > Tim, I have been using the variableRowHeight (see my original example). Also, one should not need to replicate the measure of mx:Text. Your example disregards internal padding elements of the Text component. I did try setActualSize combined with getExplicitOrMeasuredHeight, but that only works in ActionScript. I encourage you to try and create a functional example. I'm fairly confident at this point that you will not get one working in MXML with mx:Text (multi-line). > > I was able to get a fully functional item renderer based on ListItemRenderer, which uses UITextField. However, in theory, one should be able to do it in MXML. With that in mind, I replaced the UITextField of my ActionScript-based renderer with mx:Text. It's probably not surprising to many that the renderer no longer behaves as expected. The height issue appears to be tied to the component in some fashion (mx:Text in this case). I'd file a defect but I haven't seen much ROI in such reports. > > --- In flexcod...@yahoogro <mailto:flexcoders%40yahoogroups.com> ups.com, "Tim Hoff" TimHoff@ wrote: > > > > > > Hi, > > > > Set the List's variableRowHeight="true" and use something like this in > > the itemRenderer: > > > > override protected function measure():void > > { > > var textLineMetrics:TextLineMetrics = comment.measureText( > > comment.text ); > > > > // should add paddingTop, paddingBottom and verticalGap to this too > > measuredHeight = textLineMetrics.height + myLinkButton.height; > > } > > > > -TH > > > > --- In flexcod...@yahoogro <mailto:flexcoders%40yahoogroups.com> ups.com, "Tracy Spratt" <tracy@> wrote: > > > > > > Sorry, no magic sauce here. I had some pixie dust somewhere, but. Was > > it > > > Asimov or Clark that said, "Any sufficiently advanced technology is > > > indistinguishable from magic"? > > > > > > > > > > > > When I needed a variable height renderer, I copied ListItemRenderer > > and > > > modified to my needs. That was the only way I could get it to work. It > > is > > > also *much* more performant than a container based renderer. The magic > > is > > > indeed in the measure() function. > > > > > > > > > > > > If you do not have a lot of items to renderer, Repeater works well > > with > > > variable heights. > > > > > > > > > > > > Tracy Spratt, > > > > > > Lariat Services, development services available > > > > > > _____ > > > > > > From: flexcod...@yahoogro <mailto:flexcoders%40yahoogroups.com> ups.com [mailto:flexcod...@yahoogro <mailto:flexcoders%40yahoogroups.com> ups.com] > > On > > > Behalf Of wubac1 > > > Sent: Saturday, April 18, 2009 2:02 AM > > > To: flexcod...@yahoogro <mailto:flexcoders%40yahoogroups.com> ups.com > > > Subject: [flexcoders] Custom List ItemRenderer / Recycling troubles > > (height > > > incorrect) > > > > > > > > > > > > > > > > > > > > > > > > > > > I'm attempting to create a very simple item renderer for mx:List. I've > > found > > > that when the dataProvider is static, there are no problems with the > > custom > > > item > > > renderer. However, when the dataProvider is dynamic, the height of the > > item > > > renderer is not correct (and scroll bars appear for each renderer with > > any > > > meaningful # of rows). I've set variableRowHeight="true" for the List. > > I've > > > also tried overriding the measure function and invaliding the size > > when a > > > dataChange event is dispatched (based on information provided on > > FlexCoders > > > in previous discussions along these lines). > > > > > > CommentRenderer.mxml: > > > > > > <?xml version="1.0" encoding="utf-8"?> > > > <mx:VBox xmlns:mx="http://www.adobe. <http://www.adobe. <http://www.adobe.com/2006/mxml> com/2006/mxml> > > > com/2006/mxml" width="100%"> > > > <mx:Script> > > > <![CDATA[ > > > override protected function measure():void > > > { > > > super.measure(); > > > measuredHeight = comment.textHeight; > > > } > > > ]]> > > > </mx:Script> > > > <mx:LinkButton label="{data.commenter.name}"/> > > > <mx:Text id="comment" width="100%" text="{data.comment}" > > > dataChange="invalidateSize()"/> > > > </mx:VBox> > > > > > > The mx:List definition: > > > > > > <mx:List id="comments" itemRenderer="com.test.CommentRenderer" > > width="100%" > > > height="100%"/> > > > > > > I've looked over the ListItemRenderer, but have so far been unable to > > glean > > > the > > > magic sauce that makes the item renderer function correctly when the > > control > > > recycles. Can someone explain / provide a functional example(s) with > > mx:Text > > > (ActionScript and MXML examples preferred, for completeness)? > > > > > >
