Hi Matt,
I put in the debugging hooks that you described and did some testing. It
looks like the getQuotesUpdated is firing properly, but the currentQuote
binding is not firing unless there's an explicit click on the DataGrid
(that is, currentEntry gets updated). So, the binding described by
<mx:Binding source="{quotes.getQuote(currentEntry.ticker)}"
destination="currentQuote"/>
doesn't appear to be firing when the getQuotesUpdated event (associated
with quotes.getQuote()) is dispatched, only when currentEntry is updated.
Any ideas?
Thanks
- rdo
> Your approach seems right on. This shouldn't make a difference, but try
> removing the
>
> <fcon:StockQuote id="currentQuote"/>
>
>
>
> and replacing it with
>
> <mx:Script>
>
> var currentQuote : mypackage.StockQuote;
>
> </mx:Script>
>
>
>
> The fact that the update works when currentEntry changes but not the
> getQuotesUpdated event is strange. You might also try changing
> currentQuote
> to setter/getter and putting in a trace to see if it's getting called when
> just getQuotesUpdated is firing. And then finally maybe put an event
> handler on your quotes object for getQuotesUpdated (you'll need to add
> [Event("getQuotesUpdated")] to the top of your quotes class) to see if it
> is
> firing when you expect.
>
>
>
> So what you're doing appears right, just need to do some more debugging to
> figure out where things are going wrong and if it starts to look like Flex
> is doing the wrong thing we can try to get more info.
>
>
>
> Matt
>
>
>
>
>
> -----Original Message-----
> From: Ryan Olson [mailto:[EMAIL PROTECTED]
> Sent: Wednesday, May 26, 2004 10:47 AM
> To: [email protected]
> Subject: [flexcoders] Data binding chain problem
>
>
>
> Hi flexcoders,
>
> Although I've had good luck with data binding in Flex in general, I'm
> stuck on one problem.
>
> The setup is kind of complicated, but basically, I've got a QuotesModel
> object that talks to a server and provides StockQuote value objects. The
> QuotesModel class has a getQuote method defined like this:
>
> [ChangeEvent("getQuoteUpdated")]
> public function getQuote(ticker:String):StockQuote {
> return __allQuotes[ticker];
> }
>
> The class also contains code that does a
> dispatchEvent({type:"getQuoteUpdated"}); whenever __allQuotes is updated
> with new data. The idea is that I want things that are bound to
> getQuote([some ticker]) to pull the new data when the getQuoteUpdated
> event is dispatched.
>
> This appears to work for simple cases, i.e. if I have a label that's
> defined like this
>
> <fcon:QuotesModel id="quotes"/>
> <!-- PortfolioEntryModel is a value object that is bound elsewhere to
> the currently selected row of a DataGrid -->
> <fcon:PortfolioEntryModel id="currentEntry"/>
> <mx:Label id="lastPrice"
> text="{quotes.getQuote(currentEntry.ticker).lastPrice}"/>
>
> In the above case, the lastPrice label gets updated correctly when the
> QuotesModel receives new data periodically from the server. However,
> when I do this:
>
> <fcon:QuotesModel id="quotes"/>
> <!-- PortfolioEntryModel is a value object that is bound elsewhere to
> the currently selected row of a DataGrid -->
> <fcon:PortfolioEntryModel id="currentEntry"/>
> <!-- create a holder for the StockQuote associated with the ticker
> property of the currently selected row (PortfolioEntryModel) -->
> <fcon:StockQuote id="currentQuote"/>
> <mx:Binding source="{quotes.getQuote(currentEntry.ticker)}"
> destination="currentQuote"/>
> <!-- now bind the label to the holder object, not the getQuote function
> result itself -->
> <mx:Label id="lastPrice" text="{currentQuote.lastPrice}"/>
>
> the lastPrice label text does _not_ get updated when QuotesModel
> dispatches its getQuoteUpdated event. For lastPrice to see the changes,
> I have to re-click on the DataGrid, which causes currentEntry to get
> re-updated, after which the bindings appear to do the rest of the work
> correctly.
>
> Is there something wrong with the approach I'm taking in which
> currentQuote serves as an intermediate holding object? I need to do it
> this way because currentQuote is actually going to be passed as a
> property of another mxml component that will encapsulate the display of
> details associated with the current entry's stock quote.
>
> I realize this is a complicated question but I need to determine whether
> my approach is wrong or there's a bug in the system somewhere. Thanks
>
> - rdo
> FinancialContent, Inc.
>
