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<DIV><FONT face=Arial size=2><SPAN class=168504815-02032006>I'm having a problem
defining a constraint that concerns a change in number of children in a
container. My intention is to check this constraint on an event, like
"onlostchild", and to prevent the action by setting the constraint's
Priority=1. My problem is to find an approach that does not subsequently
trigger a violation when the user chooses the 'Check All' action of the
Constraint Manager.</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=168504815-02032006></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=168504815-02032006>It is my current
belief that there is no way to define such a constraint. The reason is
that the focus of this constraint is "change", whereas the focus of the
Constraint Manager, in general, is "current
state". Constraints concerning "change" typically
involve knowing "state before" and "state after". Have I failed to
consider something?</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=168504815-02032006></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=168504815-02032006>One thing that
occurs to me is that the Constraint Manager might consider not checking
constraints on "Check All" that are checked on events with Priority=1. The
intuition is that, since such event-based constraints can only result in
aborting the action, there is simply no reason to check them again on "Check
All". </SPAN></FONT><FONT face=Arial size=2><SPAN
class=168504815-02032006>Such a feature would allow the desired constraint to be
defined quite simply with a "false" predicate.</SPAN></FONT></DIV>
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