Mac Forum / Programming / CodeWarrior / February 2004

dans l'article 4beb34a4.0401221104.364ee7df@posting.google.com, Jorge à
rgasparini29@yahoo.com a écrit le 22/01/04 20:04 :

It's possible, but it's certainly not a good design. CFArrays and
CFMutableArrays are useful to store objects, that is references, so you
would end up allocating every single struct.

CFMutableData seems more appropriate since it allows you to store arrays of
structs.

Eric

C++?

SomeStruct        *pSomeStruct;

pSomeStruct = new SomeStruct();
// or use a malloc

// checking for NULL is a good option...
...

...

SomeStruct        *pSomeOtherStruct;

pSomeOtherStruct = (SomeStruct *)::CFArrayGetValueAtIndex( someArray,
somevalidIndex );

you'll have to iterate the array and deallocate everything yourself when
you clean up but you kind of have to do that anyway (for structs).

hth,
H.

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As eveyrone else has already pointed out, CFArrays store a 4-byte
value, so it's not necessarily a great idea. The STL solution is
probably better in many respects (e.g, less work, less resources).

In order to do what you want in a CF-savvy way, you'd have to create
other reference-based objects, including other CF types. You don't
necesarily have to use something you allocated with new.

For example, a struct can easily be turned into a generic CFData object
and stuck into the array. You can also try a dictionary. I have one
project where time is not so critical, but the ability to modify the
Dictionary contents at a much later time _is_. There are also lost of
examples where the OS returns CFArrays of CFDicts. In my experience, a
CFArray of CFStrings can be wicked excellent for a particular set of
circumstances. I've done a lot of this in the recent past, and it's
pretty easy.

Certainly most instances of CFArrays of objects is too much work, and
too much overhead, but you have to weigh the pros and cons.  There's no
single "right" way.