QPtrDictIterator Class Reference
The QPtrDictIterator class provides an iterator for QPtrDict collections.
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#include <qptrdict.h>
Inherits QGDictIterator.
List of all member functions.
Public Members
Detailed Description
The QPtrDictIterator class provides an iterator for
QPtrDict collections.
QPtrDictIterator is implemented as a template class.
Define a template instance QPtrDictIterator<X> to create a
dictionary iterator that operates on QPtrDict<X> (dictionary of X*).
Example:
#include <qptrdict.h>
#include <stdio.h>
void main()
{
int *a = new int[12];
int *b = new int[10];
int *c = new int[18];
int *d = new int[13];
QPtrDict<char> dict; // maps void* -> char*
dict.insert( a, "a is int[12]" ); // describe pointers
dict.insert( b, "b is int[10]" );
dict.insert( c, "c is int[18]" );
QPtrDictIterator<char> it( dict ); // iterator for dict
while ( it.current() ) {
printf( "%x -> %s\n", it.currentKey(), it.current() );
++it;
}
}
Program output:
804a788 -> a is int[12]
804a7f0 -> c is int[18]
804a7c0 -> b is int[10]
Note that the traversal order is arbitrary, you are not guaranteed the
order above.
Multiple iterators may independently traverse the same dictionary.
A QPtrDict knows about all iterators that are operating on the dictionary.
When an item is removed from the dictionary, QPtrDict update all
iterators that are referring the removed item to point to the next item
in the traversing order.
See also QPtrDict and Collection Classes
Member Function Documentation
QPtrDictIterator::QPtrDictIterator ( const QPtrDict<type> & dict )
Constructs an iterator for dict. The current iterator item is
set to point on the first item in the dict.
QPtrDictIterator::~QPtrDictIterator ()
Destroys the iterator.
QPtrDictIterator::operator type * () const
Cast operator. Returns a pointer to the current iterator item.
Same as current().
uint QPtrDictIterator::count () const
Returns the number of items in the dictionary this iterator operates on.
See also isEmpty().
type * QPtrDictIterator::current () const
Returns a pointer to the current iterator item.
void * QPtrDictIterator::currentKey () const
Returns the key for the current iterator item.
bool QPtrDictIterator::isEmpty () const
Returns TRUE if the dictionary is empty, i.e. count() == 0. Returns FALSE
otherwise.
See also count().
type * QPtrDictIterator::operator() ()
Makes the succeeding item current and returns the original current item.
If the current iterator item was the last item in the dictionary or if it
was null, null is returned.
type * QPtrDictIterator::operator++ ()
Prefix ++ makes the succeeding item current and returns the new current
item.
If the current iterator item was the last item in the dictionary or if it
was null, null is returned.
type * QPtrDictIterator::operator+= ( uint jump )
Sets the current item to the item jump positions after the current item,
and returns a pointer to that item.
If that item is beyond the last item or if the dictionary is empty,
it sets the current item to null and returns null.
type * QPtrDictIterator::toFirst ()
Sets the current iterator item to point to the first item in the
dictionary and returns a pointer to the item.
If the dictionary is empty it sets the current item to null and
returns null.
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