Re: java guy struggling with C++
nthali wrote:
// reordered message
The problem i have is: the next() method in the iterator doesn't really
give me the original object in the list, so changing the values within
that object don't change the original object.
Anyone have any ideas on how to fix this?
The problem is that the iterator needs to store a reference to the
list. Your code is storing a copy. Here is an implementation of
Iterator that fixes the main problem and also doesn't need your
'started' bool:
#include <list>
template <class T> class List;
template <class T>
class Iterator
{
public:
Iterator(List<T>& myList)
: myList(myList)
, iter(myList.begin())
{
}
bool hasNext() const
{
return iter != myList.end();
}
T& next()
{
return *iter++;
}
private:
std::list<T>& myList;
typename std::list<T>::iterator iter;
};
Note the 'typename': it is required, although your compiler may have
let it pass.
template <class T>
class List
{
friend class Iterator;
public:
void add(T obj);
T* get(int i);
int size();
Iterator<T> iterator();
T* toArray();
private:
list<T> _list;
};
I won't comment too much on List itself, since you didn't provide the
implementation, but 'get' should probably return a reference and you'd
better think carefully about what toArray is doing (unlike vector, you
can't use the address of the first element of a list as an array).
James
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