Qt Reference Documentation

Q3IntDictIterator Class Reference

The Q3IntDictIterator class provides an iterator for Q3IntDict collections. More...

 #include <Q3IntDictIterator>

This class is part of the Qt 3 support library. It is provided to keep old source code working. We strongly advise against using it in new code. See Porting to Qt 4 for more information.

Public Functions

Q3IntDictIterator ( const Q3IntDict<type> & dict )
~Q3IntDictIterator ()
uint count () const
type * current () const
long currentKey () const
bool isEmpty () const
type * toFirst ()
operator type * () const
type * operator() ()
type * operator++ ()
type * operator+= ( uint jump )

Detailed Description

The Q3IntDictIterator class provides an iterator for Q3IntDict collections.

Q3IntDictIterator is implemented as a template class. Define a template instance Q3IntDictIterator<X> to create a dictionary iterator that operates on Q3IntDict<X> (dictionary of X*).

Example:

 Q3IntDict<QLineEdit> fields;
 for ( int i = 0; i < 3; i++ )
     fields.insert( i, new QLineEdit( this ) );

 fields[0]->setText( "Homer" );
 fields[1]->setText( "Simpson" );
 fields[2]->setText( "45" );

 Q3IntDictIterator<QLineEdit> it( fields );
 for ( ; it.current(); ++it )
     cout << it.currentKey() << ": " << it.current()->text() << endl;

 // Output (random order):
 //      0: Homer
 //      1: Simpson
 //      2: 45

Note that the traversal order is arbitrary; you are not guaranteed the order shown above.

Multiple iterators may independently traverse the same dictionary. A Q3IntDict knows about all the iterators that are operating on the dictionary. When an item is removed from the dictionary, Q3IntDict updates all iterators that refer the removed item to point to the next item in the traversal order.

See also Q3IntDict.

Member Function Documentation

Q3IntDictIterator::Q3IntDictIterator ( const Q3IntDict<type> & dict )

Constructs an iterator for dict. The current iterator item is set to point to the 'first' item in the dict. The first item refers to the first item in the dictionary's arbitrary internal ordering.

Q3IntDictIterator::~Q3IntDictIterator ()

Destroys the iterator.

uint Q3IntDictIterator::count () const

Returns the number of items in the dictionary this iterator operates over.

See also isEmpty().

type * Q3IntDictIterator::current () const

Returns a pointer to the current iterator item.

long Q3IntDictIterator::currentKey () const

Returns the key for the current iterator item.

bool Q3IntDictIterator::isEmpty () const

Returns TRUE if the dictionary is empty; otherwise eturns FALSE.

See also count().

type * Q3IntDictIterator::toFirst ()

Sets the current iterator item to point to the first item in the dictionary and returns a pointer to the item. The first item refers to the first item in the dictionary's arbitrary internal ordering. If the dictionary is empty it sets the current item to 0 and returns 0.

Q3IntDictIterator::operator type * () const

Cast operator. Returns a pointer to the current iterator item. Same as current().

type * Q3IntDictIterator::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 0, 0 is returned.

type * Q3IntDictIterator::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 0, 0 is returned.

type * Q3IntDictIterator::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 0 and returns 0.