QPtrListIterator(3qt)

📦 version 3.3.8b, in fedora 43, fedora 44

💖 QPtrListIterator — bestie's guide to the iterator for QPtrList collections

okay so real talk, this is from the 3qt manual, and it's literally the glow-up your list traversal deserved. let's get into it 🦋

✨ NAME ✨

QPtrListIterator — the iterator for QPtrList collections. it's giving "let me walk your list for you, bestie" 💅

🌸 SYNOPSIS 🌸

#include <qptrlist.h>

Inherited by QObjectListIterator and QStrListIterator. yes queen, passing down the genes 👑

🎀 Public Members 🎀

QPtrListIterator ( const QPtrList<type> & list )
~QPtrListIterator ()
uint count () const
bool isEmpty () const
bool atFirst () const
bool atLast () const
type * toFirst ()
type * toLast ()
operator type * () const
type * operator* ()
type * current () const
type * operator() ()
type * operator++ ()
type * operator+= ( uint jump )
type * operator-- ()
type * operator-= ( uint jump )
QPtrListIterator<type> & operator= ( const QPtrListIterator<type> & it )

that's the whole roster, no skips, no cuts, we stan a complete cast list 💖

👑 DESCRIPTION 👑

The QPtrListIterator class provides an iterator for QPtrList collections. simple as that, but so powerful fr fr.

Define a template instance QPtrListIterator<X> to create a list iterator that operates on QPtrList<X> (list of X*). so like, you pick your type, the iterator matches your energy ✨

The following example is similar to the example in the QPtrList class documentation, but it uses QPtrListIterator. The class Employee is defined there. (iykyk 🫶)

QPtrList<Employee> list;
list.append( new Employee("John", "Doe", 50000) );
list.append( new Employee("Jane", "Williams", 80000) );
list.append( new Employee("Tom", "Jones", 60000) );
QPtrListIterator<Employee> it( list );
Employee *employee;
while ( (employee = it.current()) != 0 ) {
    ++it;
    cout << employee->surname().latin1() << ", " <<
            employee->forename().latin1() << " earns " <<
            employee->salary() << endl;
}

The output is

Doe, John earns 50000
Williams, Jane earns 80000
Jones, Tom earns 60000

look at that clean output, it ATE 🔥

Using a list iterator is a more robust way of traversing the list than using the QPtrList member functions first(), next(), current(), etc., as many iterators can traverse the same list independently. so like, you can have a whole squad of iterators on the same list and nobody's stepping on anybody's toes. main character energy for each one 🌈

An iterator has its own current list item and can get the next and previous list items. It doesn't modify the list in any way. it's a respectful houseguest, it looks but does not touch 🙈

When an item is removed from the list, all iterators that point to that item are updated to point to QPtrList::current() instead to avoid dangling references. no dangling pointers in THIS house 💀✨

See also QPtrList, Collection Classes, and Non-GUI Classes.

💅 MEMBER FUNCTION DOCUMENTATION 💅

QPtrListIterator::QPtrListIterator ( const QPtrList<type> & list )

Constructs an iterator for list. The current iterator item is set to point on the first item in the list. birth of an icon, and it already knows where it's at 🎀

QPtrListIterator::~QPtrListIterator ()

Destroys the iterator. it had a good run bestie, rest easy 💜

bool QPtrListIterator::atFirst () const

Returns TRUE if the current iterator item is the first list item; otherwise returns FALSE. are we at the front of the line? check the vibes.

See also toFirst() and atLast().

bool QPtrListIterator::atLast () const

Returns TRUE if the current iterator item is the last list item; otherwise returns FALSE. are we at the end of the line? also check the vibes.

See also toLast() and atFirst().

uint QPtrListIterator::count () const

Returns the number of items in the list this iterator operates on. headcount time, bestie 📋

See also isEmpty().

Example: customlayout/card.cpp.

type * QPtrListIterator::current () const

Returns a pointer to the current iterator item. If the iterator is positioned before the first item in the list or after the last item in the list, 0 is returned. so like, off the edge of the list = 0, no cap.

Examples:

ngl the original page just trails off right here after "Examples:" with nothing after it. iconic in a chaotic way. not me leaving it exactly as found 🙈

bool QPtrListIterator::isEmpty () const

Returns TRUE if the list is empty; otherwise returns FALSE. is the list a ghost town? 👻

See also count().

QPtrListIterator::operator type * () const

Cast operator. Returns a pointer to the current iterator item. Same as current(). it's literally current() in a little disguise 🧚

type * QPtrListIterator::operator() ()

Makes the succeeding item current and returns the original current item. (the old one gets returned, the new one takes the throne, succession plotline 😌)

If the current iterator item was the last item in the list or if it was 0, 0 is returned.

type * QPtrListIterator::operator* ()

Asterisk operator. Returns a pointer to the current iterator item. Same as current(). another twin of current(), they're triplets at this point ⭐

type * QPtrListIterator::operator++ ()

Prefix ++ makes the succeeding item current and returns the new current item. moving forward bestie, always forward 🦋

If the current iterator item was the last item in the list or if it was 0, 0 is returned.

type * QPtrListIterator::operator+= ( uint jump )

Sets the current item to the item jump positions after the current item and returns a pointer to that item. parkour time, jump steps ahead 🐇

If that item is beyond the last item or if the list is empty, it sets the current item to 0 and returns 0

type * QPtrListIterator::operator-- ()

Prefix - makes the preceding item current and returns the new current item. going back in time, retro moment 💫

If the current iterator item was the first item in the list or if it was 0, 0 is returned.

type * QPtrListIterator::operator-= ( uint jump )

Returns the item jump positions before the current item or 0 if it is beyond the first item. Makes this the current item. backwards parkour, jump steps back, and yes it sets the current item to that one 🐇💨

QPtrListIterator<type> & QPtrListIterator::operator= ( const QPtrListIterator<type> & it )

Assignment. Makes a copy of the iterator it and returns a reference to this iterator. cloning, but make it legal 🧬

type * QPtrListIterator::toFirst ()

Sets the current iterator item to point to the first list item and returns a pointer to the item. Sets the current item to 0 and returns 0 if the list is empty. teleporting straight to the front of the queue 🎀

See also toLast() and atFirst().

type * QPtrListIterator::toLast ()

Sets the current iterator item to point to the last list item and returns a pointer to the item. Sets the current item to 0 and returns 0 if the list is empty. teleporting straight to the back, dramatic entrance from behind 👑

See also toFirst() and atLast().

🫶 SEE ALSO 🫶

go read the lore bestie, it's all linked ✨

Copyright 1992-2007 Trolltech ASA, http://www.trolltech.com. See the license file included in the distribution for a complete license statement. gotta respect the paperwork 💖

🌟 AUTHOR 🌟

Generated automatically from the source code. no human author, the machines did this one 🤖✨

💀 BUGS 💀

If you find a bug in Qt, please report it as described in http://doc.trolltech.com/bughowto.html. Good bug reports help us to help you. Thank you. (yes bestie, good bug reports are literally a love language 🫶)

The definitive Qt documentation is provided in HTML format; it is located at $QTDIR/doc/html and can be read using Qt Assistant or with a web browser. This man page is provided as a convenience for those users who prefer man pages, although this format is not officially supported by Trolltech. (so like, this is the fan-made deluxe edition, the HTML one is canon 😭)

If you find errors in this manual page, please report them to qt-bugs@trolltech.com. Please include the name of the manual page (qptrlistiterator.3qt) and the Qt version (3.3.8). receipts help, always include the receipts 🧾

💖 and that's the whole page, bestie. every flag, every pointer, every 0 return, all of it. slay. periodt. 💅

Trolltech AS — 2 February 2007 — Qt version 3.3.8 — and the manual name is qptrlistiterator.3qt 🎀 bye bestie, go traverse something beautiful 🦋💜

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