I haven't tried explicitly re-setting the value manually or with BindingUtils,
but that's something I'll try now! Should still be working without that.
I have a feeling the problem is actually in the display logic of the component.
Like perhaps some built-in efficiency code to ignore binding updates when it's
hidden. But I'll have to deep-dive a little further to verify that. It's more
likely something I'm missing or doing wrong.
--- In flexcoders@yahoogroups.com, yang chen <chenyang3@...> wrote:
>
> Have you tried using binding util?
>
> > To: flexcoders@yahoogroups.com
> > From: nick14@...
> > Date: Fri, 16 Mar 2012 20:08:47 +0000
> > Subject: [flexcoders] Bindings on visual components being forgotten? (Flex
> > 3 -> 4.6)
> >
> > Seeing a strange, rare, issue after updating an app to 4.6. I can't seem
> > to reproduce it in a dev environment, so I'll list out my issue and setup
> > to see if it sounds familiar to anyone.
> >
> > The problem:
> > Visual components seem to occasionally "forget" the objects they're bound
> > to. For instance, I have something like this:
> >
> > <s:DropDownList
> > id="cmbMonth"
> > dataProvider="{model.months}"
> > selectedItem="@{model.selectedMonth}"
> > />
> > <s:Label text="{model.selectedMonth}" />
> >
> > When the problem occurs, the "selectedMonth" in the label component is
> > correct, say, February. But the DropDownList will display a blank. Even
> > though the DropDownList contains all the months, meaning models.months is
> > bound correctly.
> >
> > I tried adding:
> > requireSelection="true"
> >
> > The addition changed the behavior. No more blanks! But now, instead of
> > blanks, selectedMonth is showing something random like "May".
> >
> > Background:
> > App has been in production in various versions of Flex 3 for two years
> > without ever seeing this. Upgrading to Flex 4 and swapping out some Halo
> > components with equivalent Spark ones, users, myself included, began
> > noticing this phenomenon. I cannot seem to reproduce it in a reliable
> > fashion. But I've gotten some feedback based on some attempted fixes
> > pushed out to users.
> >
> > Troubleshooting so far:
> > Since it normally works, there's no super-obvious things missing, like an
> > uninitialized pointer, missing "Bindable" tag, accidental = assignment
> > instead of == comparison, etc.
> >
> > Also, we know the variable references are pointing to the correct place.
> > model.selectedMonth is showing up fine for a label just underneath the
> > dropdown. model.months is being referenced just fine by the dropdown
> > itself. It's just the display of model.selectedMonth in the dropdown.
> > Upon saving, the model.month property correctly propagates itself to the
> > DB, even when the dropdown is displaying the wrong value. Switching
> > between one-way and two-way bindings don't seem to make a difference
> > either. I noted above that I tried forcing requireSelection="true", which
> > does prevent the DropDownList from being blanked-out, but doesn't force it
> > to stay on the correct value.
> >
> > I thought it might be related to just the DropDownList component, but the
> > problem is also occurring on s:TextInput's text property. Seems like when
> > it happens with the TextInput component (showing a blank value), it's doing
> > so for all the TextInput components. I'm not so sure if it's happening for
> > all DropDownList elements, though.
> >
> >
> > App setup:
> > I have an mx:ViewStack attached to hide/show effects with two containers
> > inside (loggedOff/loggedOn), and a TabNavigator within that. I think the
> > problems are only occurring after switching between states for the
> > ViewStack. So after the components are hidden and come back. I remembered
> > back to the Flex 2 ViewStack issue where bindings didn't refresh, and added
> > the old workaround to my code:
> > change="executeBindings(true)"
> >
> > This didn't fix it. Anything else I can look at or try? Anyone else
> > experience this before? Any chance it's related to the framework instead
> > of my code?
> >
> >
> >
> > ------------------------------------
> >
> > --
> > Flexcoders Mailing List
> > FAQ: http://groups.yahoo.com/group/flexcoders/files/flexcodersFAQ.txt
> > Alternative FAQ location:
> > https://share.acrobat.com/adc/document.do?docid=942dbdc8-e469-446f-b4cf-1e62079f6847
> > Search Archives:
> > http://www.mail-archive.com/flexcoders%40yahoogroups.comYahoo! Groups Links
> >
> >
> >
>
