Mattias Gaertner wrote:
On Thu, 05 Oct 2006 10:45:25 +0200
Marc Weustink <[EMAIL PROTECTED]> wrote:
[...]
Modified needs to be modified :)
procedure Modified;
begin
SendBeginModificationToAllBeginEndObeservers;
SendModifiedNotificationToAllModifiedObeservers;
SendEndModificationToAllBeginEndObeservers;
end;
But then Begin/End is useless, isn't it? The modification took
place before 'Begin'. For example:
NewToolButton.Parent:=CurToolBar;
Modified;
Indeed, I was more thinking of controls reacting on the
ModifiedNotification which would trigger more modifications.
In your example, an editor sets the Parent and calls Modified. Why
would setting the parent trigger other code which will call
Modified ? Afterall, Modified is a Designer/Editor method, and
should/can not be called from the component itself. So I see no
chain of modified there.
There are some components, that call Modified. For example
changing the PageIndex of a TNoteBook. But this is very rare and
can be changed. Let's ignore these things.
More important is that we don't have a working Begin/End
enclosement. So, we can only react, but not prepare. Or in other
words: Only a OnModified event, but no OnChanging.
At the moment the solution is to swallow the bitter pill and
implement a dynamic property propagation system. The more
information the changer (e.g. OI) provides, the less the system
will copy. The OI can call BeginUpdate/ChangeProperty/EndUpdate,
while others can call Modified and the whole forms are
scanned/copied.
Whats wrong with adapting modified ?
That is the difference of having one OnModified, or having observers
which subscribe themselves to begen/end notifications
Begin/EndUpdate and notifications are a good idea and needed.
I'm just unhappy, that there is no more elegant solution for copying
the data to the descendants.
It may be the case, but, what would a elegant way help if it isn't used
that often.
I mean, you need this to be able to efficiently update descendant forms.
How often will one edit ancestor while descendants are open.
So question is, is the efford needed
Marc
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