I see your point; that inheritance can be considered evil in some
situations. In this case though, I think that it's ok; since a MatRix
is an Array; or in this case an ArrayCollection. However, I do agree
that you can just as easily create a stand-alone MatRix class as well.
Like you say, it depends on the use-case.
-TH
--- In flexcoders@yahoogroups.com, Richard Rodseth <rrods...@...> wrote:
>
> Limited time, and not sure what the original goal is. But if the
poster
> needs a Matrix class he can make one that doesn't derive from
anything, or
> that implements an interface. In fact, if you look at
flash.geom.Matrix
> you'll see it derives from Object.
>
> Googling "composition vs inheritance" or "delegation vs inheritance"
should
> yield lots of guidance on the general principle.
>
> HTH
>
> On Tue, Apr 28, 2009 at 3:39 PM, Tim Hoff timh...@... wrote:
>
> >
> >
> >
> > Care to elaborate with an example?
> >
> > -TH
> >
> >
> > --- In flexcoders@yahoogroups.com <flexcoders%40yahoogroups.com>,
Richard
> > Rodseth rrodseth@ wrote:
> > >
> > > I wouldn't extend either of these. Favour delegation over
inheritance.
> > >
> > > On Tue, Apr 28, 2009 at 3:23 PM, Tim Hoff TimHoff@ wrote:
> > >
> > > >
> > > >
> > > > Yep, thought that I could get away with not testing it. Doesn't
look
> > like
> > > > you can extend Array, but you can extend ArrayCollection:
> > > >
> > > > *package
> > > > *{
> > > > * import* mx.collections.ArrayCollection;
> > > > *
> > > > public* *class* MatRix *extends* ArrayCollection
> > > > {
> > > > * public* *function* MatRix(numRows:int=0,numCols:int=0)
> > > > {
> > > > * for* (*var* i:int=0;i<numRows;i++)
> > > > {
> > > > * this*.addItem( *new* Array(numCols) );
> > > > }
> > > > }
> > > > }
> > > > }
> > > >
> > > > Test:
> > > >
> > > > *var* a:MatRix = *new* MatRix(3,3);
> > > > a[0][1] = *"test"*;
> > > > *trace*(a[0][1]);
> > > >
> > > > -TH
> > > >
> > > > --- In flexcoders@yahoogroups.com
<flexcoders%40yahoogroups.com>,
> > "smitade" smitade@ wrote:
> > > > >
> > > > > This compiles OK but fails at this point in the class:
> > > > >
> > > > > this[i]=new Array(numCols);
> > > > >
> > > > > with the error: Cannot create property 0 on [the class] i.e i
> > being 0 on
> > > > the first for loop when calling:
> > > > >
> > > > > var a:MatRix = new MatRix(3,3);
> > > > >
> > > >
> > > >
> > >
> >
> >
> >
>
