Re: having trouble programmatically selecting CListCtrl item
"Joseph M. Newcomer" <newcomer@flounder.com> wrote in message
news:qm95h5ph0j6fui18mkvnps7kvscnrdngos@4ax.com...
Subclassing is usually a better solution. The problem with putting the
logic in the
parent is that it has to know the details of the implementation of the
controls, which is
actually a violation of modularity
It depends. Custom Draw differentiates from Owner Draw in that it is a
light-weight (supposedly) easier way for the parent to specify colors and
fonts used for various situations. I am not sure the custom draw message is
reflected; if it were, you could use custom draw in your subclass. If not,
you are stuck with owner draw in your subclass which is not as high-level
(although custom draw has a real finicky multistate system of callbacks
which is bizarre, so that distracts from any productivity you gain).
But I don't know if I would subclass everything just to get a different
color or font in some cases. The parent knows exactly what the desired
appearance should be, which might be so specialized it doesn't make sense to
subclass. Subclassing involves overhead of maintaining additional files and
if the specialized behavior is not going to be reused (since it is so
specialized) then it doesn't make sense to subclass. In addition, MFC is
often used for RAD scenarios where it is not known ahead of time what is
going to be reused often and what is going to be thrown away. In that case,
putting the code in the parent without subclassing is definitely better.
My own view is that the natural reaction to any custom situation should be
to derive a
subclass. Someone once posted a question that started out "I am opposed
to subclassing,
and I need a solution..." which struck me as one of the dumbest positions
I had ever heard
anyone take; that morning I had already written six new subclasses, two
for CListBox, one
for pushbuttons, one for a CListCtrl, and two for CStatic. It struck me
as someone saying
"I have a flat tire, but I think a car jack is a bad idea, and I'd like to
change the tire
without one..."
The situation here is more like "I have a flat tire, but it is a slow leak,
and I don't want to get dirty right now, so I am going to refill the tire
and drive to my destination and worry about a more permanent fix later."
-- David