How to get better information than “undefined” from Flash Builder (Flex 3.5)?

1
votes

I've seen "undefined" all by itself in the console window before, but I could figure out what it meant. This time, I'm getting it in the opening line of the constructor for CollectionEvent (super(type, bubbles, cancelable);). I think it was triggered by a write to an XMLListCollection. There doesn't seem to be anything undefined about it--the this pointer looks good and all that parameters do, too. It has rather a large stack trace but no helpful information about what's undefined. How do I get to the next debugging step?

undefined
    at mx.events::CollectionEvent()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\events\CollectionEvent.as:116]
    at mx.collections::ListCollectionView/handlePropertyChangeEvents()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\collections\ListCollectionView.as:1245]
    at mx.collections::ListCollectionView/listChangeHandler()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\collections\ListCollectionView.as:1120]
    at flash.events::EventDispatcher/dispatchEventFunction()
    at flash.events::EventDispatcher/dispatchEvent()
    at mx.collections::XMLListAdapter/itemUpdateHandler()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\collections\XMLListAdapter.as:523]
    at mx.collections::XMLListAdapter/itemUpdated()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\collections\XMLListAdapter.as:321]
    at mx.collections::XMLListAdapter/xmlNotification()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\collections\XMLListAdapter.as:620]
    at Function/()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\utils\XMLNotifier.as:81]
    at AddressNode/DisplayLinesInLabels()[C:\Users\PL\Documents\projects\AMHS-FlexProject\src\ubimex\modules\MTARoutingControl\AddressNode.as:192]
    at AddressTree/DisplayLinesInLabels()[C:\Users\PL\Documents\projects\AMHS-FlexProject\src\ubimex\modules\MTARoutingControl\AddressTree.as:37]
    at UMTAControl/ValidateDisplayLines_()[C:\Users\PL\Documents\projects\AMHS-FlexProject\src\ubimex\modules\MTARoutingControl\UMTAControl.as:90]
    at UMTAControl/OnChangeXML()[C:\Users\PL\Documents\projects\AMHS-FlexProject\src\ubimex\modules\MTARoutingControl\UMTAControl.as:82]
    at UMTAControl/OnChXML()[C:\Users\PL\Documents\projects\AMHS-FlexProject\src\ubimex\modules\MTARoutingControl\UMTAControl.as:79]
    at flash.events::EventDispatcher/dispatchEventFunction()
    at flash.events::EventDispatcher/dispatchEvent()
    at mx.collections::ListCollectionView/dispatchEvent()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\collections\ListCollectionView.as:879]
    at mx.collections::ListCollectionView/handlePropertyChangeEvents()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\collections\ListCollectionView.as:1248]
    at mx.collections::ListCollectionView/listChangeHandler()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\collections\ListCollectionView.as:1120]
    at flash.events::EventDispatcher/dispatchEventFunction()
    at flash.events::EventDispatcher/dispatchEvent()
    at mx.collections::XMLListAdapter/itemUpdateHandler()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\collections\XMLListAdapter.as:523]
    at mx.collections::XMLListAdapter/itemUpdated()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\collections\XMLListAdapter.as:321]
    at mx.collections::XMLListAdapter/xmlNotification()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\collections\XMLListAdapter.as:620]
    at Function/()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\utils\XMLNotifier.as:81]
    at AddressNode/DisplayLinesInLabels()[C:\Users\PL\Documents\projects\AMHS-FlexProject\src\ubimex\modules\MTARoutingControl\AddressNode.as:192]
    at AddressTree/DisplayLinesInLabels()[C:\Users\PL\Documents\projects\AMHS-FlexProject\src\ubimex\modules\MTARoutingControl\AddressTree.as:37]
    at UMTAControl/ValidateDisplayLines_()[C:\Users\PL\Documents\projects\AMHS-FlexProject\src\ubimex\modules\MTARoutingControl\UMTAControl.as:90]
    at UMTAControl/OnChangeXML()[C:\Users\PL\Documents\projects\AMHS-FlexProject\src\ubimex\modules\MTARoutingControl\UMTAControl.as:82]
    at UMTAControl/OnChXML()[C:\Users\PL\Documents\projects\AMHS-FlexProject\src\ubimex\modules\MTARoutingControl\UMTAControl.as:79]
    at flash.events::EventDispatcher/dispatchEventFunction()
    at flash.events::EventDispatcher/dispatchEvent()
    at mx.collections::ListCollectionView/dispatchEvent()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\collections\ListCollectionView.as:879]
    at mx.collections::ListCollectionView/handlePropertyChangeEvents()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\collections\ListCollectionView.as:1248]
    at mx.collections::ListCollectionView/listChangeHandler()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\collections\ListCollectionView.as:1120]
    at flash.events::EventDispatcher/dispatchEventFunction()
    at flash.events::EventDispatcher/dispatchEvent()
    at mx.collections::XMLListAdapter/itemUpdateHandler()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\collections\XMLListAdapter.as:523]
    at mx.collections::XMLListAdapter/itemUpdated()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\collections\XMLListAdapter.as:321]
    at mx.collections::XMLListAdapter/xmlNotification()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\collections\XMLListAdapter.as:620]
    at Function/()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\utils\XMLNotifier.as:81]
    at AddressNode/DisplayLinesInLabels()[C:\Users\PL\Documents\projects\AMHS-FlexProject\src\ubimex\modules\MTARoutingControl\AddressNode.as:192]
    at AddressTree/DisplayLinesInLabels()[C:\Users\PL\Documents\projects\AMHS-FlexProject\src\ubimex\modules\MTARoutingControl\AddressTree.as:37]
    at UMTAControl/ValidateDisplayLines_()[C:\Users\PL\Documents\projects\AMHS-FlexProject\src\ubimex\modules\MTARoutingControl\UMTAControl.as:90]
    at UMTAControl/OnChangeXML()[C:\Users\PL\Documents\projects\AMHS-FlexProject\src\ubimex\modules\MTARoutingControl\UMTAControl.as:82]
    at UMTAControl/OnChXML()[C:\Users\PL\Documents\projects\AMHS-FlexProject\src\ubimex\modules\MTARoutingControl\UMTAControl.as:79]
    at flash.events::EventDispatcher/dispatchEventFunction()
    at flash.events::EventDispatcher/dispatchEvent()
    at mx.collections::ListCollectionView/dispatchEvent()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\collections\ListCollectionView.as:879]
    at mx.collections::ListCollectionView/handlePropertyChangeEvents()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\collections\ListCollectionView.as:1248]
    at mx.collections::ListCollectionView/listChangeHandler()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\collections\ListCollectionView.as:1120]
    at flash.events::EventDispatcher/dispatchEventFunction()
    at flash.events::EventDispatcher/dispatchEvent()
    at mx.collections::XMLListAdapter/itemUpdateHandler()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\collections\XMLListAdapter.as:523]
    at mx.collections::XMLListAdapter/itemUpdated()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\collections\XMLListAdapter.as:321]
    at mx.collections::XMLListAdapter/xmlNotification()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\collections\XMLListAdapter.as:620]
    at Function/()[C:\autobuild\3.5.0\frameworks\projects\framework\src\mx\utils\XMLNotifier.as:81]
    at AddressNode/DisplayLinesInLabels()[C:\Users\PL\Documents\projects\AMHS-FlexProject\src\ubimex\modules\MTARoutingControl\AddressNode.as:192]
    at AddressTree/DisplayLinesInLabels()[C:\Users\PL\Documents\projects\AMHS-FlexProject\src\ubimex\modules\MTARoutingControl\AddressTree.as:37]
    at UMTAControl/ValidateDisplayLines_()[C:\Users\PL\Documents\projects\AMHS-FlexProject\src\ubimex\modules\MTARoutingControl\UMTAControl.as:90]
    at UMTAControl/OnChangeXML()[C:\Users\PL\Documents\projects\AMHS-FlexProject\src\ubimex\modules\MTARoutingControl\UMTAControl.as:82]
    at UMTAControl/OnChXML()[C:\Users\PL\Documents\projects\AMHS-FlexProject\src\ubimex\modules\MTARoutingControl\UMTAControl.as:79]
    at flash.events::EventDispatcher/dispatchEventFunction()
    at flash.events::EventDispatcher/dispatchEvent()
1
apache-flexdebuggingflash-builder
Put a breakpoint at line 79 of UMTAControl.as and then click "step into" a lot; be careful to check things each step of the way. – JeffryHouser
I think what is undefined in this case is the actual error message. Normally, in a stack trace, that's where the error text would be. Follow the advice above, you might even set your breakpoint a little higher in the stack trace at AddressNode.as line 192. Though this all seems very odd, not sure how helpful stepping the code will be. – Sunil D.
So many repeated lines. Some kind of recursion for XML... or stack overflow? However, you are lucky to have stack trace. Debugging adt crashes is much more...interesting. – user1875642

1 Answers

0
votes

That's right, those other instances of "undefined" were all due to infinite recursion causing stack overflow (and not the kind that gives well-thought feedback).

I imagined these callbacks were similar to the MFC model, where messages were queued and only processed when the app developer's code was finished executing (and I think duplicate messages might have been merged sometimes). Clearly that's not what's going on here--a change is being made and the callback is executed immediately. I guess I won't be able to reliably detect changes to this XMLListCollection :(

Thanks guys.