You're probably wrong. Anything registered with callLater is kept alive by its
registration. The call stack indicates that code in your class at line 490 is
using anull reference. That could be because you cleaned up something before
callLater came through. A simple null check there should solve the problem
From: flexcoders@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of
christian.menzinger
Sent: Tuesday, November 04, 2008 8:39 AM
To: flexcoders@yahoogroups.com
Subject: [flexcoders] callLater calls from framework / validation after
instances are already removed
Hi all,
I have a very special problem:
By selecting an item in my navigation I start rendering my view with several
display objects (container, components, ...).
Every time I select an other item, I remove all stuff from display list
(destroying all bindings, remove all listeners, setting everything to null).
If I do very quick changes, after a while I receive null-pointer exceptions in
different classes in different validation methods (measure / updateDisplayList)
like
TypeError: Error #1009: Cannot access a property or method of a null object
reference.
at package::ClassName/updateDisplayList()[ClassName.as:490]
at
mx.core::UIComponent/validateDisplayList()[framework\src\mx\core\UIComponent.as:6293]
at
mx.managers::LayoutManager/validateDisplayList()[framework\src\mx\managers\LayoutManager.as:605]
at
mx.managers::LayoutManager/doPhasedInstantiation()[framework\src\mx\managers\LayoutManager.as:660]
at Function/http://adobe.com/AS3/2006/builtin::apply()
at
mx.core::UIComponent/callLaterDispatcher2()[framework\src\mx\core\UIComponent.as:8565]
at
mx.core::UIComponent/callLaterDispatcher()[framework\src\mx\core\UIComponent.as:8508]
The exception stack trace starts always by callLaterDispatcher like above.
I think the null-pointer happen because the render engine applies a call later
for rendering in the next frame, unfortunately I removed the instanced in time
between and so all my component children are null.
That brings me to the following questions:
- Could it be true that fl! ex forces validation via callLater even if the
instance is rem! oved? Ho w could this be?
- If so, how can I solve the problem proper (e.g. remove all callLaters in my
destroy functions - btw: there is a mx_internal function cancelAllCallLaters()
in UIComponent but that is not working for me - no effect if I call this
function in my destroy functions)
- Or am I completely wrong and the problem is part of my custom components
development?
If you have any ideas or solutions which can guide me in the right direction
would be very cool.
Thanks a lot
Chris
