I noticed that some interfaces have a base and client.  This might seem like a stupid question but what's the difference between Base and Client?  If I change the font size on the Base, it doesn't change it on the client so I assume I have to change it on both?

= Steve

Steve,

<< I noticed that some interfaces have a base and client.  This might seem
like a stupid question but what's the difference between Base and Client? >>

No, that's actually a very good, fundamental question.

Rule number one is:  for all TControl descendants, the Base element=the
control.  TControl is essentially just a wrapper around the Base TElement
that hides all of the "TElement-y" properties and methods and surfaces them
as "TControl-y" properties and methods.

The base TControl control maps the Client element to the Base element, so
for basic controls the two are the same.  For things like containers, the
Client becomes the actual client area and has a separately-created UI
element to allow for scrolling, headers, etc.  By default, controls that are
parented to a given control are placed into this Client UI element. You can
use these TControl methods (protected) to change how a given control
"attaches" or "is attached" to a given parent control:

        procedure AddControlElement(AControl: TControl); virtual;
        procedure SetParentElement(AParent: TControl); virtual;

This is useful for things like headers and other non-client-area controls
that need to be attached to a container control, but aren't part of the
client area with other "normal" controls.

<< If I change the font size on the Base, it doesn't change it on the client
so I assume I have to change it on both? >>

Yes, as I replied in the other thread, each UI element has its own
distinctive set of properties, and nothing is inherited.  When you have a
lot of inheritance of properties, performance starts to go south quickly
because each UI element has to constantly keep checking its parents for
changes, and each parent has to constantly keep broadcasting its property
changes to its children.

Tim Young
Elevate Software
www.elevatesoft.com

Thanks Tim, I appreciate you explaining that.

Tim,

thanks for this detailed explanation.

Maybe you could explain "ApplyProperties" as well. We spoke about that in some mails, but I think, it's of general interest.

Thanks Uli

Uli,

<< Maybe you could explain "ApplyProperties" as well. We spoke about that in
some mails, but I think, it's of general interest. >>

All of this will be explained in the manual.  Right now I'm way behind
because I stopped to re-do the standard interfaces, so I've got to
concentrate on getting things done for the final release.

Tim Young
Elevate Software
www.elevatesoft.com