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Help me... please... object array problems...

Hi, I need to make an array of object pointers which is probably one of the easiest things to implement but I can't get my brain to wrap around this...

I create an object like this:

CMyObject * myObj = new CMyObject;

then I allocate some space in an array which is defined as a "void *", cast it to an array of pointers (CMyObject*)? and then assign the pointer to the new object to the end of the list:

declared as --> void * myList = NULL;

myNewList = realloc (myList, (numItems + 1) * sizeof (CMyObject *));
if (myNewList != NULL)
{
myList = myNewList;
CMyObject * objectPtrList = (CMyObject *)myList;
objectPtrList[numItems] = myObj;
numItems ++;
}

Now, I'm kind of constrained as this code needs to adhere to the "void *" for storing the array and the memory must be allocated with malloc/realloc except for objects such as CMyObject...

The compiler I use complains at the assignment of objectPtrList[numItems]....

-- Bubba

jkr

You should bettr use a 'std::list', e.g. like

#include <list>
using namespace std;

list<CMyObject*> myList;

CMyObject * myObj = new CMyObject;

myList.push_back (myObj);

//...

list<CMyObject*>::iterator i = myList.begin();

CMyObject * object = *i;

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zekard

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kyleleber

It looks like your assignment:

objectPtrList[numItems] = myObj;

is trying to assign a pointer to an object.

myObj is type (CMyObject *)
objectPtrList expects type (CMyObject).

Try dereferencing myObj in the assignment:

objectPtrList[numItems] = *myObj; //If this is what you are trying to do

bganoush

ASKER

Zekard,

>> objectPtrList = (CMyObject **)myList;
>> objectPtrList[numItems] = myObj;

Oops! I knew that!

What I tried before was something like this:

CMyObject ** objectPtrList = (CMyObject *)myList;
objectPtrList[numItems] = myObj;

I forgot to cast "myList" to a pointer to pointers...

Thanks!

jkr

>>I forgot to cast "myList" to a pointer to pointers...

1st of all, your list is not a list, but an array of pointers. 2nd, why would ypu want to reinvent the wheel?

bganoush

ASKER

1st:

English is not my first language, "list" sounds much closer to what it is called in my language. Thank you for correcting my unsuitably bad translation...

2nd:

It is what is expected of me... The management I am working with requires me to send an array of pointers to their precious engine. ie: red tape

But thank you so very much for caring!

-- Bubba