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November 26, 2003
Re: Modern Features?
In article <bq36c5$17nc$2@digitaldaemon.com>, Berin Loritsch says... 
>You can
tell where I've been playing can't you? ;P 
> 
>The thing that delegates have
going for them is that they are strongly typed. 
>I'm not familiar with Qt's
signal/slots approach, so I can't comment on that. 
> 
>Think about it though,
do you really need to subclass a delegate? 
>I can't think of a good reason to
myself. 

No, I can't and that is pretty much my point.  Why make it an object
in its 
own right when you can't even subclass it?  Qt's signal/slots are also
typesafe, but do not have the syntactical overheard of C#'s delegates. 

Here
is what they look like: 

You define the signal/slots in the header files of
the QObject subclasses like 
so. 

class Foo: QObject 
{ 
       Q_OBJECT
slots: 
	void add( int x, int y ); 
}; 

class Bar: QObject 
{
Q_OBJECT 
signals: 
	void calculate( int x, int y ); 
}; 

then the slot could
be... 

void Foo::add( int x, int y) 
{ 
	print ( x + y ); 
} 

and you'd
connect them like... 

	connect( &foo, SIGNAL(calculate(int,int), &bar,
SLOT(add(int,int)) ); 

and then you'd emit the signal like so... 

	emit
calculate( 1, 1 ); 

and the slot is called.  Of course, you can
connect/disconnect as many slots 
to a signal as you wish.  You can also connect
signals to signals.  All very 
sane and without the overhead of the delegates.
Of course, I'd like to see a 
'+=' or '~=' operator for the connect call, but
other than that I think it is 
much nicer... 

Here is an overview:
http://www.trolltech.com/products/qt/whitepaper/qt-whitepaper-3.html
November 26, 2003
Re: Modern Features?
In article <bq39p8$1d8c$1@digitaldaemon.com>, Adam Treat says... 

Sorry about
the odd formatting. I'm using the forum html form direct from the 
website.  Not
sure why it is wrapping everything...
November 26, 2003
Re: Modern Features?
Ahh, ive seen that before so thought it was some weird client :).

C


"Adam Treat" <Adam_member@pathlink.com> wrote in message
news:bq39sk$1df3$1@digitaldaemon.com...
> In article <bq39p8$1d8c$1@digitaldaemon.com>, Adam Treat says...
>
> Sorry about
> the odd formatting. I'm using the forum html form direct from the
> website.  Not
> sure why it is wrapping everything...
>
>
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