Qt Documentation

Qt Designer

void asciify(QByteArray array)
{
    for (int i = 0; i < (int)array.size(); ++i) {
        if ((uchar)array[i] >= 128)
            array[i] = '?';
    }
}
void asciify(QByteArray &array)
{
    for (int i = 0; i < array.size(); ++i) {
        if ((uchar)array[i] >= 128)
            array[i] = '?';
    }
}
    QWidgetList *list = QApplication::topLevelWidgets();
    QWidgetListIt it(*list);
    QWidget *widget;
    while ((widget = it.current())) {
        if (widget->inherits("MainWindow"))
            ((MainWindow *)widget)->updateRecentFileItems();
        ++it;
    }
    delete list;
    QWidgetList list = QApplication::topLevelWidgets();
    for (int i = 0; i < list.size(); ++i) {
        if (MainWindow *mainWin = qobject_cast<MainWindow *>(list.at(i)))
            mainWin->updateRecentFileItems();
    }
void MyButton::paintEvent(QPaintEvent *)
{
    QPainter painter(this);
    drawButton(&painter);
}
QByteArray ba(64);
QByteArray ba(64, '\0');
ba.at(0) = 'X';
ba[0] = 'X';
if (!cache.insert(key, object))
    delete object;
cache.insert(key, object);
Q3Cache<QWidget> cache;
cache.insert(widget->name(), widget);
...
QWidget *foo = cache.take("foo");
if (foo)
    foo->show();
typedef QWidget *QWidgetPtr;
QCache<QString, QWidgetPtr> cache;
cache.insert(widget->name(), new QWidgetPtr(widget));
...
QWidgetPtr *ptr = cache.take("foo");
if (ptr) {
    QWidget *foo = *ptr;
    delete ptr;
    foo->show();
}
QColor lightCyan = Qt::cyan.light(180);
QColor lightCyan = QColor(Qt::cyan).light(180);
painter.setBrush(colorGroup().brush(QColorGroup::Text));
painter.setBrush(palette().brush(QPalette::Text));
QByteArray ba("Hello");
ba.size();             // returns 5 (the '\0' is not counted)
ba.length();           // returns 5
ba.data()[5];          // returns '\0'
    QCString str1("Hello", 4);           // "Hel"
    QCString str2("Hello world!", n);
    QByteArray str1("Hello", 3);
    QByteArray str2("Hello world!");
    str2.truncate(n - 1);
    QCString str("Hello world");
    str.setExpand(16, '\n');            // "Hello world     \n"
    QByteArray str("Hello world");
    while (str.size() < 16)
        str += ' ';
    str += '\n';
QString str1 = "I am a string";
QDeepCopy<QString> str2 = str1;
QString str3 = QDeepCopy<QString>(str2);
QString str1 = "I am a string";
QString str2 = str1;
QString str3 = str2;
dict.replace(key, value);
delete hash.take(key);
hash.insert(key, value);
dict.remove(key, value);
delete hash.take(key);
dict.clear();
while (!hash.isEmpty()) {
    T *value = *hash.begin();
    hash.erase(hash.begin());
    delete value;
}
qDeleteAll(hash);
hash.clear();
Q3DictIterator<QWidget> i(dict);
while (i.current() != 0) {
    do_something(i.currentKey(), i.current());
    ++i;
}
QHashIterator<QString, QWidget *> i(hash);
while (i.hasNext()) {
    i.next();                   // must come first
    do_something(i.key(), i.value());
}
QDir dir("/home/tsmith");
QString path = dir.filePath(fileName, false);
QDir dir("/home/tsmith");
QString path;
if (dir.isRelativePath(fileName))
    path = dir.filePath(fileName);
else
    path = fileName;
class MyWidget : public QWidget, public QDropSite
{
public:
    MyWidget(const QWidget *parent)
        : QWidget(parent), QDropSite(this)
    {
    }
    ...
}
class MyWidget : public QWidget
{
public:
    MyWidget(const QWidget *parent)
        : QWidget(parent)
    {
        setAcceptDrops(true);
    }
    ...
}
    fileDialog->addFilter(tr("JPEG files (*.jpg *.jpeg)"));
    QStringList filters = fileDialog->filters();
    filters << tr("JPEG files (*.jpg *.jpeg)");
    fileDialog->setFilters(filters);
    fileDialog->setSelectedFilter(3);
    fileDialog->selectFilter(fileDialog->filters().at(3));
QGrid *grid = new QGrid(2, Qt::Horizontal);
QPushButton *child1 = new QPushButton(grid);
QPushButton *child2 = new QPushButton(grid);
QPushButton *child3 = new QPushButton(grid);
QPushButton *child4 = new QPushButton(grid);
QWidget *grid = new QWidget;
QPushButton *child1 = new QPushButton(grid);
QPushButton *child2 = new QPushButton(grid);
QPushButton *child3 = new QPushButton(grid);
QPushButton *child4 = new QPushButton(grid);

QVBoxLayout *layout = new QVBoxLayout;
layout->addWidget(child1, 0, 0);
layout->addWidget(child2, 0, 1);
layout->addWidget(child3, 1, 0);
layout->addWidget(child4, 1, 1);
grid->setLayout(layout);
QHBox *hbox = new QHBox;
QPushButton *child1 = new QPushButton(hbox);
QPushButton *child2 = new QPushButton(hbox);
QWidget *hbox = new QWidget;
QPushButton *child1 = new QPushButton;
QPushButton *child2 = new QPushButton;

QHBoxLayout *layout = new QHBoxLayout;
layout->addWidget(child1);
layout->addWidget(child2);
hbox->setLayout(layout);
    QLayoutIterator it = layout()->iterator();
    QLayoutItem *child;
    while ((child = it.current()) != 0) {
        if (child->widget() == myWidget) {
            it.takeCurrent();
            return;
        ++it;
    }
    int i = 0;
    QLayoutItem *child;
    while ((child = layout()->itemAt(i)) != 0) {
        if (child->widget() == myWidget) {
            layout()->takeAt(i);
            return;
        }
        ++i;
    }
    QMemArray<QSize> array;
    ...
    array.assign(data, size);
    QVector<QSize> vector;
    ...
    vector.resize(size);
    qCopy(data, data + size, vector.begin());
QList<QWidget *> myWidgets = myParent->findChildren<QWidget *>();
    QPaintDeviceMetrics metrics(widget);
    int deviceDepth = metrics.depth();
    int deviceDepth = widget->depth();
    if (pixmap.mask())
        widget->setMask(*pixmap.mask());
    if (!pixmap.mask().isNull())
        widget->setMask(pixmap.mask());
    QPtrList<QWidget> list;
    ...
    QPtrVector<QWidget> vector;
    list.toVector(&vector);
    QList<QWidget *> list;
    ...
    QVector<QWidget *> vector;
    vector.resize(list.size());
    qCopy(list.begin(), list.end(), vector.begin());
list.replace(index, value);
delete list[index];
list[index] = value;
list.removeFirst();
delete list.takeFirst();
list.removeLast();
delete list.takeLast();
list.remove(index);
delete list.takeAt(index);
list.remove(value);
int i = list.indexOf(value);
if (i != -1)
    delete list.takeAt(i);
list.remove();
QMutableListIterator<T *> i;
...
delete i.value();
i.remove();
list.clear();
while (!list.isEmpty())
    delete list.takeFirst();
qDeleteAll(list);
list.clear();
QPtrList<QWidget> list;
...
while (list.current() != 0) {
    do_something(list.current());
    list.next();
}
QList<QWidget *> list;
...
QListIterator<QWidget *> i(list);
while (i.hasNext())
    do_something(i.next());
QPtrList<QWidget> list;
...
QPtrListIterator<QWidget> i;
while (i.current() != 0) {
    do_something(i.current());
    i.next();
}
QList<QWidget *> list;
...
QListIterator<QWidget *> i(list);
while (i.hasNext())
    do_something(i.next());
queue.dequeue();
delete queue.dequeue();
queue.remove();
delete queue.dequeue();
queue.clear();
while (!queue.isEmpty())
    delete queue.dequeue();
qDeleteAll(queue);
queue.clear();
stack.pop();
delete stack.pop();
stack.remove();
delete stack.pop();
stack.clear();
while (!stack.isEmpty())
    delete stack.pop();
qDeleteAll(stack);
stack.clear();
    int numValidItems = vect.count();
    int numValidItems = vect.size() - vect.count(0);
vect.insert(i, ptr);
delete vect[i];
vect[i] = ptr;
vect.remove(i);
delete vect[i];
vect[i] = 0;
T *ptr = vect.take(i);
T *ptr = vect[i];
vect[i] = 0;
vect.resize(n)
while (n > vect.size())
    vect.append(0);
while (n < vect.size() {
    T *ptr = vect.last();
    vect.remove(vect.size() - 1);
    delete ptr;
}
vect.clear();
for (int i = 0; i < vect.size(); ++i)
    T *ptr = vect[i];
    vect[i] = 0;
    delete ptr;
}
qDeleteAll(vect);
vect.clear();
    class VolumeControl : public QWidget, public QRangeControl
    {
        ...
    protected:
        void valueChange() {
            update();
            emit valueChanged(value());
        }
        void rangeChange() {
            update();
        }
        void stepChange() {
            update();
        }
    };
    class VolumeControl : public QAbstractSlider
    {
        ...
    protected:
        void sliderChange(SliderChange change) {
            update();
            if (change == SliderValueChange)
                emit valueChanged(value());
        }
    };
struct Shared
{
    Shared() : count(1) {}
    void ref() { ++count; }
    bool deref() { return !--count; }
    uint count;
};
// Declare the object
QSimpleRichText richText(text, font);

// Set the width of the paragraph to w
richText.setWidth(w);

// Or set a reasonable default size
richText.adjustSize();

// Query for its used size
int width = richText.widthUsed();
int height = richText.height();

// Draw
richText.draw(painter, x, y, clipRect, colorGroup);
// Declare the object
QTextDocument doc;

// If text is rich text, use setHtml()
doc.setHtml(text);

// Otherwise, use setPlainText()
doc.setPlainText(text);

// Set the width of the paragraph of text to w
doc.setTextWidth(w);

// Query for the used size
int width = doc.idealWidth();
int height = doc.size().height();

// Draw
painter.translate(x, y);
doc.drawContents(painter, clipRect);

// If you have a palette/colorgroup you can draw using lower-level functions:
QAbstractTextDocumentLayout::PaintContext context;
context.palette = myPalette;
doc.documentLayout()->draw(painter, context);
QSlider *slider;
slider->style()->subControlRect(CC_Slider, sliderOption, SC_SliderHandle, slider);
        str1 = QString::null;
        if (str2 == QString::null)
            do_something(QString::null);
        str1.clear();
        if (str2.isNull())
            do_something(QString());
QString greeting = "Hello";
const char *badData = greeting.toAscii().constData(); // data is invalid
QByteArray asciiData = greeting.toAscii();
const char *goodData = asciiData.constData();
str.at(0) = 'X';
str[0] = 'X';
        if (url.startsWith("http:", false))
            ...
        if (url.startsWith("http:", Qt::CaseInsensitive))
            ...
        str.setExpand(32, '$');
        str[32] = '$';
    for (QValueList<T>::iterator i = list.fromLast(); i != list.begin(); --i)
        do_something(*i);
    QLinkedList<T>::iterator i = list.end();
    while (i != list.begin()) {
        --i; // decrement i before using it
        do_something(*i);
    }
QVBox *vbox = new QVBox;
QPushButton *child1 = new QPushButton(vbox);
QPushButton *child2 = new QPushButton(vbox);
QWidget *vbox = new QWidget;
QPushButton *child1 = new QPushButton;
QPushButton *child2 = new QPushButton;

QVBoxLayout *layout = new QVBoxLayout;
layout->addWidget(child1);
layout->addWidget(child2);
vbox->setLayout(layout);

Qt 3 function	Qt 4 function
T qt_cast<T >(QObject *)	T qobject_cast<T >(QObject *)
	T qgraphicsitem_cast<T>(QGraphicsItem *)
	T qstyleoption_cast<T>(QStyleOption *)
	T qvariant_cast<T>(const QVariant &)
	T qdbus_cast(const QDBusArgument &)

Qt 3 class name	Qt 4 class name
QIconSet	QIcon
QWMatrix	QMatrix
QGuardedPtr	QPointer

Qt 3 type name	Qt 4 type name
QApplication::ColorMode	QApplication::ColorSpec
QButton::ToggleState	QCheckBox::ToggleState
QCursorShape	Qt::CursorShape
QFile::FilterSpec	QFile::Filters
QFile::PermissionSpec	QFile::Permission
QFile::SortSpec	QFile::SortFlags
QFile::Status	QFile::Error
QFileInfo::PermissionSpec	QFile::Permission
QGrid::Direction	Qt::Orientation
QGridWidget::Direction	Qt::Orientation
QIODevice::Offset	qlonglong
QImage::ScaleMode	Qt::AspectRatioMode
QSize::ScaleMode	Qt::AspectRatioMode
QSocket::Error	Q3Socket::Error
QSocket::State	Q3Socket::State
QStyle::SCFlags	QStyle::SubControls
QStyle::SFlags	QStyle::State
QTS	QTextStream
QUrlDrag	QUriDrag
QWidget::FocusPolicy	Qt::FocusPolicy
Q_LLONG	qlonglong
Q_ULLONG	qulonglong
Qt::Dock	Qt::ToolBarDock
Qt::MacintoshVersion	QSysInfo::MacVersion
Qt::TextFlags	Qt::TextFlag
Qt::WindowsVersion	QSysInfo::WinVersion

Qt 3 type	Qt 4 equivalent
Qt::WDestructiveClose	Use QWidget::setAttribute(Qt::WA_DeleteOnClose) instead.
Qt::WStaticContents	Use QWidget::setAttribute(Qt::WA_StaticContents) instead.
Qt::WNorthWestGravity	Use QWidget::setAttribute(Qt::WA_StaticContents) instead.
Qt::WNoAutoErase	Use QWidget::setAttribute(Qt::WA_NoBackground) instead.
Qt::WResizeNoErase
Qt::WRepaintNoErase
Qt::WPaintClever	Unnecessary in Qt 4.
Qt::WMacNoSheet	Unnecessary in Qt 4.

Qt 3 type	Qt 4 equivalent
Qt::WShowModal	Use QWidget::setWindowModality(Qt::ApplicationModal) instead.
Qt::WGroupLeader	Use QWidget::setWindowModality(Qt::WindowModal) for each child dialog of the group leader, but do not change the modality of the group leader itself.

Qt 3 enum value name	Qt 4 enum value name
IO_Append	QIODevice::Append
IO_ReadOnly	QIODevice::ReadOnly
IO_ReadWrite	QIODevice::ReadWrite
IO_Translate	QIODevice::Text
IO_Truncate	QIODevice::Truncate
IO_WriteOnly	QIODevice::WriteOnly
IO_Raw	QIODevice::Unbuffered
QAccessible::Moveable	QAccessible::Movable
QApplication::CustomColors	QApplication::CustomColor
QApplication::NormalColors	QApplication::NormalColor
QButton::NoChange	QCheckBox::NoChange
QButton::Off	QCheckBox::Off
QButton::On	QCheckBox::On
QChar::Single	QChar::NoDecomposition
QChar::byteOrderMark	QChar::ByteOrderMark
QChar::byteOrderSwapped	QChar::ByteOrderSwapped
QChar::nbsp	QChar::Nbsp
QChar::null	QChar::Null
QChar::replacement	QChar::ReplacementCharacter
QComboBox::AfterCurrent	QComboBox::InsertAfterCurrent
QComboBox::AtBottom	QComboBox::InsertAtBottom
QComboBox::AtCurrent	QComboBox::InsertAtCurrent
QComboBox::AtTop	QComboBox::InsertAtTop
QComboBox::BeforeCurrent	QComboBox::InsertBeforeCurrent
QComboBox::NoInsertion	QComboBox::NoInsert
QDir::DefaultFilter	QDir::NoFilter
QDir::DefaultSort	QDir::NoSort
QEvent::Accel	QEvent::Shortcut
QEvent::AccelOverride	QEvent::ShortcutOverride
QEvent::CaptionChange	QEvent::WindowTitleChange
QEvent::ChildInserted	QEvent::ChildAdded
QEvent::IMCompose	QEvent::InputMethodCompose
QEvent::IMEnd	QEvent::InputMethodEnd
QEvent::IMStart	QEvent::InputMethodStart
QEvent::IconChange	QEvent::WindowIconChange
QEvent::LayoutHint	QEvent::LayoutRequest
QEvent::Reparent	QEvent::ParentChange
QFileInfo::ExeGroup	QFile::ExeGroup
QFileInfo::ExeOther	QFile::ExeOther
QFileInfo::ExeOwner	QFile::ExeOwner
QFileInfo::ExeUser	QFile::ExeUser
QFileInfo::ReadGroup	QFile::ReadGroup
QFileInfo::ReadOther	QFile::ReadOther
QFileInfo::ReadOwner	QFile::ReadOwner
QFileInfo::ReadUser	QFile::ReadUser
QFileInfo::WriteGroup	QFile::WriteGroup
QFileInfo::WriteOther	QFile::WriteOther
QFileInfo::WriteOwner	QFile::WriteOwner
QFileInfo::WriteUser	QFile::WriteUser
QFrame::GroupBoxPanel	QFrame::StyledPanel
QFrame::LineEditPanel	QFrame::StyledPanel
QFrame::MenuBarPanel	QFrame::StyledPanel
QFrame::PopupPanel	QFrame::StyledPanel
QFrame::TabWidgetPanel	QFrame::StyledPanel
QFrame::ToolBarPanel	QFrame::StyledPanel
QImage::ScaleFree	Qt::IgnoreAspectRatio
QImage::ScaleMax	Qt::KeepAspectRatioByExpanding
QImage::ScaleMin	Qt::KeepAspectRatio
Qt::Identical	QKeySequence::ExactMatch
Qt::NoMatch	QKeySequence::NoMatch
Qt::PartialMatch	QKeySequence::PartialMatch
QLayout::Auto	QLayout::SetDefaultConstraint
QLayout::Fixed	QLayout::SetFixedSize
QLayout::FreeResize	QLayout::SetNoConstraint
QLayout::Minimum	QLayout::SetMinimumSize
QMacStyle::SizeNone	QMacStyle::SizeDefault
QSettings::Global	QSettings::SystemScope
QSettings::User	QSettings::UserScope
QSize::ScaleFree	Qt::IgnoreAspectRatio
QSize::ScaleMax	Qt::KeepAspectRatioByExpanding
QSize::ScaleMin	Qt::KeepAspectRatio
QSizePolicy::Horizontal	QSizePolicy::Horizontally
QSizePolicy::Vertical	QSizePolicy::Vertically
QSlider::Above	QSlider::TicksAbove
QSlider::Below	QSlider::TicksBelow
QSlider::Both	QSlider::TicksBothSides
QSlider::Left	QSlider::TicksLeft
QSlider::NoMarks	QSlider::NoTicks
QSlider::Right	QSlider::TicksRight
QSocket::Closing	Q3Socket::Closing
QSocket::Connected	Q3Socket::Connected
QSocket::Connecting	Q3Socket::Connecting
QSocket::Connection	Q3Socket::Connection
QSocket::ErrConnectionRefused	Q3Socket::ErrConnectionRefused
QSocket::ErrHostNotFound	Q3Socket::ErrHostNotFound
QSocket::ErrSocketRead	Q3Socket::ErrSocketRead
QSocket::HostLookup	QAbstractSocket::HostLookupState
QSocket::Idle	QAbstractSocket::UnconnectedState
QSqlError::Connection	QSqlError::ConnectionError
QSqlError::None	QSqlError::NoError
QSqlError::Statement	QSqlError::StatementError
QSqlError::Transaction	QSqlError::TransactionError
QSqlError::Unknown	QSqlError::UnknownError
QStyle::CC_ListView	QStyle::CC_Q3ListView
QStyle::SH_UnderlineAccelerator	QStyle::SH_UnderlineShortcut
QStyle::Style_Active	QStyle::State_Active
QStyle::Style_AutoRaise	QStyle::State_AutoRaise
QStyle::Style_Bottom	QStyle::State_Bottom
QStyle::Style_Children	QStyle::State_Children
QStyle::Style_Default	QStyle::State_None
QStyle::Style_Down	QStyle::State_DownArrow
QStyle::Style_Editing	QStyle::State_Editing
QStyle::Style_Enabled	QStyle::State_Enabled
QStyle::Style_FocusAtBorder	QStyle::State_FocusAtBorder
QStyle::Style_HasFocus	QStyle::State_HasFocus
QStyle::Style_Horizontal	QStyle::State_Horizontal
QStyle::Style_Item	QStyle::State_Item
QStyle::Style_MouseOver	QStyle::State_MouseOver
QStyle::Style_NoChange	QStyle::State_NoChange
QStyle::Style_None	QStyle::State_None
QStyle::Style_Off	QStyle::State_Off
QStyle::Style_On	QStyle::State_On
QStyle::Style_Open	QStyle::State_Open
QStyle::Style_Raised	QStyle::State_Raised
QStyle::Style_Rectangle	QStyle::State_Rectangle
QStyle::Style_Selected	QStyle::State_Selected
QStyle::Style_Sibling	QStyle::State_Sibling
QStyle::Style_Sunken	QStyle::State_Sunken
QStyle::Style_Top	QStyle::State_Top
QStyle::Style_Up	QStyle::State_Up
QTabBar::RoundedAbove	QTabBar::RoundedNorth
QTabBar::RoundedBelow	QTabBar:: RoundedSouth
QTabBar::TriangularAbove	QTabBar:: TriangularNorth
QTabBar::TriangularBelow	QTabBar:: TriangularSouth
QTextEdit::MovePgDown	QTextEdit::MovePageDown
QTextEdit::MovePgUp	QTextEdit::MovePageUp
QToolButton::Right	QToolButton::BesideIcon
QToolButton::Under	QToolButton::BelowIcon
QValidator::Valid	QValidator::Intermediate
QVariant::IconSet	QCoreVariant::Icon
QWidget::ClickFocus	Qt::ClickFocus
QWidget::NoFocus	Qt::NoFocus
QWidget::StrongFocus	Qt::StrongFocus
QWidget::TabFocus	Qt::TabFocus
QWidget::WheelFocus	Qt::WheelFocus
Qt::AlignAuto	Qt::AlignLeft
Qt::AltButton	Qt::AltModifier
Qt::Ascending	Qt::AscendingOrder
Qt::Bottom	Qt::DockBottom
Qt::BottomLeft	Qt::BottomLeftCorner
Qt::BottomRight	Qt::BottomRightCorner
Qt::BreakAnywhere	Qt::TextWrapAnywhere
Qt::ControlButton	Qt::ControlModifier
Qt::CustomPattern	Qt::TexturePattern
Qt::Descending	Qt::DescendingOrder
Qt::DontClip	Qt::TextDontClip
Qt::DontPrint	Qt::TextDontPrint
Qt::ExpandTabs	Qt::TextExpandTabs
Qt::IncludeTrailingSpaces	Qt::TextIncludeTrailingSpaces
Qt::KeyButtonMask	Qt::KeyboardModifierMask
Qt::Key_BackSpace	Qt::Key_Backspace
Qt::Key_BackTab	Qt::Key_Backtab
Qt::Key_MediaPrev	Qt::Key_MediaPrevious
Qt::Key_Next	Qt::Key_PageDown
Qt::Key_Prior	Qt::Key_PageUp
Qt::Key_aacute	Qt::Key_Aacute
Qt::Key_acircumflex	Qt::Key_Acircumflex
Qt::Key_adiaeresis	Qt::Key_Adiaeresis
Qt::Key_ae	Qt::Key_AE
Qt::Key_agrave	Qt::Key_Agrave
Qt::Key_aring	Qt::Key_Aring
Qt::Key_atilde	Qt::Key_Atilde
Qt::Key_ccedilla	Qt::Key_Ccedilla
Qt::Key_eacute	Qt::Key_Eacute
Qt::Key_ecircumflex	Qt::Key_Ecircumflex
Qt::Key_ediaeresis	Qt::Key_Ediaeresis
Qt::Key_egrave	Qt::Key_Egrave
Qt::Key_eth	Qt::Key_ETH
Qt::Key_iacute	Qt::Key_Iacute
Qt::Key_icircumflex	Qt::Key_Icircumflex
Qt::Key_idiaeresis	Qt::Key_Idiaeresis
Qt::Key_igrave	Qt::Key_Igrave
Qt::Key_ntilde	Qt::Key_Ntilde
Qt::Key_oacute	Qt::Key_Oacute
Qt::Key_ocircumflex	Qt::Key_Ocircumflex
Qt::Key_odiaeresis	Qt::Key_Odiaeresis
Qt::Key_ograve	Qt::Key_Ograve
Qt::Key_oslash	Qt::Key_Ooblique
Qt::Key_otilde	Qt::Key_Otilde
Qt::Key_thorn	Qt::Key_THORN
Qt::Key_uacute	Qt::Key_Uacute
Qt::Key_ucircumflex	Qt::Key_Ucircumflex
Qt::Key_udiaeresis	Qt::Key_Udiaeresis
Qt::Key_ugrave	Qt::Key_Ugrave
Qt::Key_yacute	Qt::Key_Yacute
Qt::Keypad	Qt::KeypadModifier
Qt::Left	Qt::DockLeft
Qt::MV_10_DOT_0	QSysInfo::MV_10_0
Qt::MV_10_DOT_1	QSysInfo::MV_10_1
Qt::MV_10_DOT_2	QSysInfo::MV_10_2
Qt::MV_10_DOT_3	QSysInfo::MV_10_3
Qt::MV_10_DOT_4	QSysInfo::MV_10_4
Qt::MV_9	QSysInfo::MV_9
Qt::MV_CHEETAH	QSysInfo::MV_10_0
Qt::MV_JAGUAR	QSysInfo::MV_10_2
Qt::MV_PANTHER	QSysInfo::MV_10_3
Qt::MV_PUMA	QSysInfo::MV_10_1
Qt::MV_TIGER	QSysInfo::MV_10_4
Qt::MV_Unknown	QSysInfo::MV_Unknown
Qt::MetaButton	Qt::MetaModifier
Qt::Minimized	Qt::DockMinimized
Qt::NoAccel	Qt::TextHideMnemonic
Qt::Overline	Qt::TextOverline
Qt::Right	Qt::DockRight
Qt::ShiftButton	Qt::ShiftModifier
Qt::ShowPrefix	Qt::TextShowMnemonic
Qt::SingleLine	Qt::TextSingleLine
Qt::StrikeOut	Qt::TextStrikeOut
Qt::Top	Qt::DockTop
Qt::TopLeft	Qt::TopLeftCorner
Qt::TopRight	Qt::TopRightCorner
Qt::TornOff	Qt::DockTornOff
Qt::Underline	Qt::TextUnderline
Qt::Unmanaged	Qt::DockUnmanaged
Qt::WNorthWestGravity	Qt::WStaticContents
Qt::WRepaintNoErase	Qt::WNoAutoErase
Qt::WStyle_Dialog	Qt::WType_Dialog
Qt::WStyle_NoBorderEx	Qt::WStyle_NoBorder
Qt::WType_Modal	(Qt::WType_Dialog \| Qt::WShowModal)
Qt::WV_2000	QSysInfo::WV_2000
Qt::WV_2003	QSysInfo::WV_2003
Qt::WV_32s	QSysInfo::WV_32s
Qt::WV_95	QSysInfo::WV_95
Qt::WV_98	QSysInfo::WV_98
Qt::WV_CE	QSysInfo::WV_CE
Qt::WV_CENET	QSysInfo::WV_CENET
Qt::WV_CE_based	QSysInfo::WV_CE_based
Qt::WV_DOS_based	QSysInfo::WV_DOS_based
Qt::WV_Me	QSysInfo::WV_Me
Qt::WV_NT	QSysInfo::WV_NT
Qt::WV_NT_based	QSysInfo::WV_NT_based
Qt::WV_XP	QSysInfo::WV_XP
Qt::WordBreak	Qt::TextWordWrap
Qt::IbeamCursor	Qt::IBeamCursor

Qt 3 name	Qt 4 name
QButton::accel	QButton::shortcut
QButton::on	QButton::checked
QButton::toggleButton	QAbstractButton::checkable
QDial::lineStep	QDial::singleStep
QDial::maxValue	QDial::maximum
QDial::minValue	QDial::minimum
QDialog::modal	QDialog::isModal
QLineEdit::edited	QLineEdit::modified
QLineEdit::hasMarkedText	QLineEdit::hasSelectedText
QLineEdit::markedText	QLineEdit::selectedText
QObject::name	QObject::objectName
QProgressDialog::progress	QProgressDialog::value
QProgressDialog::totalSteps	QProgressDialog::maximum
QProgressDialog::wasCancelled	QProgressDialog::wasCanceled
QPushButton::iconSet	QPushButton::icon
QScrollBar::draggingSlider	QScrollBar::sliderDown
QScrollBar::lineStep	QScrollBar::singleStep
QScrollBar::maxValue	QScrollBar::maximum
QScrollBar::minValue	QScrollBar::minimum
QSlider::lineStep	QSlider::singleStep
QSlider::maxValue	QSlider::maximum
QSlider::minValue	QSlider::minimum
QSpinBox::lineStep	QSpinBox::singleStep
QSpinBox::maxValue	QSpinBox::maximum
QSpinBox::minValue	QSpinBox::minimum
QTabBar::currentTab	QTabBar::currentIndex
QTabWidget::currentPage	QTabWidget::currentWidget
QToolButton::iconSet	QToolButton::icon
QToolButton::textLabel	QToolButton::text
QWidget::caption	QWidget::windowTitle
QWidget::icon	QWidget::windowIcon
QWidget::iconText	QWidget::windowIconText

Qt 3 property	Qt 4 read function	Qt 4 write function
QSqlDatabase::connectOptions	QSqlDatabase::connectOptions()	QSqlDatabase::setConnectOptions()
QSqlDatabase::databaseName	QSqlDatabase::databaseName()	QSqlDatabase::setDatabaseName()
QSqlDatabase::hostName	QSqlDatabase::hostName()	QSqlDatabase::setHostName()
QSqlDatabase::password	QSqlDatabase::password()	QSqlDatabase::setPassword()
QSqlDatabase::port	QSqlDatabase::port()	QSqlDatabase::setPort()
QSqlDatabase::userName	QSqlDatabase::userName()	QSqlDatabase::setUserName()

Qt 3 property	Qt 4 read function (`QT3_SUPPORT`)	Qt 4 write function (`QT3_SUPPORT`)
QMenuBar::separator	QMenuBar::separator()	QMenuBar::setSeparator()
QPushButton::menuButton	QPushButton::isMenuButton()	N/A
QTabWidget::margin	QTabWidget::margin()	QTabWidget::setMargin()
QTextEdit::textFormat	QTextEdit::textFormat()	QTextEdit::setTextFormat()
QWidget::backgroundBrush	QWidget::backgroundBrush()	N/A
QWidget::backgroundMode	QWidget::backgroundMode()	QWidget::setBackgroundMode()
QWidget::backgroundOrigin	QWidget::backgroundOrigin()	QWidget::setBackgroundOrigin()
QWidget::colorGroup	QWidget::colorGroup()	QWidget::setColorGroup()
QWidget::customWhatsThis	QWidget::customWhatsThis()	QWidget::setCustomWhatsThis()
QWidget::inputMethodEnabled	QWidget::inputMethodEnabled()	QWidget::setInputMethodEnabled()
QWidget::ownCursor	QWidget::ownCursor()	N/A
QWidget::ownFont	QWidget::ownFont()	N/A
QWidget::ownPalette	QWidget::ownPalette()	N/A
QWidget::paletteBackgroundColor	QWidget::paletteBackgroundColor()	QWidget::setPaletteBackgroundColor()
QWidget::paletteBackgroundPixmap	QWidget::paletteBackgroundPixmap()	QWidget::setPaletteBackgroundPixmap()
QWidget::paletteForegroundColor	QWidget::paletteForegroundColor()	QWidget::setPaletteForegroundColor()
QWidget::underMouse	QWidget::underMouse()	N/A

Qt 3 property	Qt 4 equivalent
QButton::autoRepeat	N/A
QButton::autoResize	Call QWidget:setFixedSize(QWidget::sizeHint()) whenever you change the contents.
QButton::exclusiveToggle	See QAbstractButton::autoExclusive.
QButton::pixmap	Use QAbstractButton::icon instead.
QButton::toggleState	Use QCheckBox::setState() and QCheckBox::state() instead.
QButton::toggleType	Use QCheckBox::setTristate() instead.
QComboBox::autoResize	Call QWidget:setFixedSize(QWidget::sizeHint()) whenever you change the contents.
QFrame::contentsRect	Use Q3Frame::contentsRect() instead.
QFrame::margin	Use QWidget::setContentsMargins() instead.
QTabBar::keyboardFocusTab	N/A
QToolButton::offIconSet	Use the off component of QAbstractButton::icon instead.
QToolButton::onIconSet	Use the on component of QAbstractButton::icon instead.
QWidget::microFocusHint	N/A
QMimeSource::serialNumber ()	N/A

Q3Button function	QAbstractButton equivalent
Q3Button::autoResize()	Call QWidget:setFixedSize(QWidget::sizeHint()) whenever you change the contents.
Q3Button::isExclusiveToggle()	Use QAbstractButton::group() or QAbstractButton::autoExclusive() instead.
Q3Button::pixmap() const	QAbstractButton::icon()
Q3Button::setAutoResize()	N/A
Q3Button::setPixmap(const QPixmap &)	QAbstractButton::setIcon(const QIcon &)
Q3Button::setState(ToggleState)	See remark below
Q3Button::setToggleType(ToggleType)	See remark below
Q3Button::state()	See remark below
Q3Button::stateChanged(int)	See remark below
Q3Button::toggleType()	See remark below

Q3Cache<T> function	QCache<QString, T> equivalent
Q3Cache::Q3Cache(int maxCost, int size, bool caseSensitive)	See remark below
Q3Cache::autoDelete()	N/A
Q3Cache::count()	QCache::count() or QCache::size() (equivalent)
Q3Cache::setAutoDelete()	See remark below
Q3Cache::size()	N/A
Q3Cache::statistics()	N/A
Q3Cache::operator=()	See remark below

Qt 3 class name	Compatibility class in Qt 4
`QCanvas`	Q3Canvas
`QCanvasEllipse`	Q3CanvasEllipse
`QCanvasItem`	Q3CanvasItem
`QCanvasItemList`	Q3CanvasItemList
`QCanvasLine`	Q3CanvasLine
`QCanvasPixmap`	Q3CanvasPixmap
`QCanvasPixmapArray`	Q3CanvasPixmapArray
`QCanvasPolygon`	Q3CanvasPolygon
`QCanvasPolygonalItem`	Q3CanvasPolygonalItem
`QCanvasRectangle`	Q3CanvasRectangle
`QCanvasSpline`	Q3CanvasSpline
`QCanvasSprite`	Q3CanvasSprite
`QCanvasText`	Q3CanvasText
`QCanvasView`	Q3CanvasView

Predefined Qt Colors
Qt::color0	Qt::color1	Qt::black	Qt::white
Qt::darkGray	Qt::gray	Qt::lightGray	Qt::red
Qt::green	Qt::blue	Qt::cyan	Qt::magenta
Qt::yellow	Qt::darkRed	Qt::darkGreen	Qt::darkBlue
Qt::darkCyan	Qt::darkMagenta	Qt::darkYellow	Qt::transparent

Q3CString function	Qt 4 equivalent
Q3CString::Q3CString(const char *, uint)	See remark below
Q3CString::Q3CString(int)	QByteArray::QByteArray(int, char)
Q3CString::leftJustify()	QString::leftJustified()
Q3CString::length()	QByteArray::length() or QByteArray::size() (equivalent)
Q3CString::lower()	QByteArray::toLower()
Q3CString::rightJustify()	QString::rightJustified()
Q3CString::setExpand()	See remark below
Q3CString::simplifyWhiteSpace()	QByteArray::simplified()
Q3CString::sprintf()	QString::sprintf()
Q3CString::stripWhiteSpace()	QByteArray::trimmed()
Q3CString::toDouble()	QString::toDouble()
Q3CString::toFloat()	QString::toFloat()
Q3CString::toInt()	QString::toInt()
Q3CString::toLong()	QString::toLong()
Q3CString::toShort()	QString::toShort()
Q3CString::toUInt()	QString::toUInt()
Q3CString::toULong()	QString::toULong()
Q3CString::toUShort()	QString::toUShort()
Q3CString::upper()	QByteArray::toUpper()

Qt 4 class	When to use it
QMultiHash<QString, T *>	Since Q3Dict<T> is pointer-based and allows duplicate keys, this is usually the most straightforward conversion.
QMultiHash<QString, T>	If type `T` is an assignable data type, you can use `T` as the value type rather than `T *`. This often leads to nicer code.
QHash<QString, T *>	If you don't use duplicate keys, you can use QHash instead of QMultiHash. QMultiHash inherits from QHash.
QHash<QString, T>

Q3Dict function	QMultiHash equivalent
Q3Dict::Q3Dict(int size, bool caseSensitive)	See remarks below
Q3Dict::autoDelete()	N/A
Q3Dict::count()	QMultiHash::count() or QMultiHash::size() (equivalent)
Q3Dict::find(const QString &)	QMultiHash::value(const QString &)
Q3Dict::remove(const QString &)	QMultiHash::take(const QString &)
Q3Dict::resize(uint)	QMultiHash::reserve(int)
Q3Dict::setAutoDelete()	See discussion below
Q3Dict::size()	QMultiHash::capacity()
Q3Dict::statistics()	N/A
Q3Dict::operator[](const QString &)	See remark below

Q3DictIterator functions	Qt 4 equivalent
Q3DictIterator::count()	QHash::count() or QHash::size()
Q3DictIterator::current()	QHashIterator::value()
Q3DictIterator::currentKey()	QHashIterator::key()
Q3DictIterator::isEmpty()	QHash::isEmpty()
Q3DictIterator::toFirst()	QHashIterator::toFront()
Q3DictIterator::operator()()	QHashIterator::value()
Q3DictIterator::operator*()	QHashIterator::value()
Q3DictIterator::operator++()	See remark below

Current directory	File name	`acceptAbsPath`	File path
/home/tsmith	index.html	true	/home/tsmith/index.html
/home/tsmith	index.html	false	/home/tsmith/index.html
/home/tsmith	/index.html	true	/index.html
/home/tsmith	/index.html	false	/home/tsmith/index.html

Old function	Qt 4 equivalent
Q3FileDialog::addFilter(const QString &)	See remark below
Q3FileDialog::addLeftWidget(QWidget *)	N/A
Q3FileDialog::addRightWidget(QWidget *)	N/A
Q3FileDialog::addToolButton(QAbstractButton *, bool separator)	N/A
Q3FileDialog::addWidgets(QLabel , QWidget , QPushButton *)	N/A
Q3FileDialog::dir()	QFileDialog::directory()
Q3FileDialog::dirPath()	QFileDialog::directory().path()
Q3FileDialog::iconProvider()	N/A
Q3FileDialog::isContentsPreviewEnabled()	N/A
Q3FileDialog::isInfoPreviewEnabled()	N/A
Q3FileDialog::previewMode()	N/A
Q3FileDialog::rereadDir()	N/A
Q3FileDialog::resortDir()	N/A
Q3FileDialog::selectAll(bool)	N/A
Q3FileDialog::setContentsPreview(QWidget , Q3FilePreview )	N/A
Q3FileDialog::setContentsPreviewEnabled(bool)	N/A
Q3FileDialog::setDir(const QString &)	QFileDialog::setDirectory(const QString &)
Q3FileDialog::setFilters(const char **)	Q3FileDialog::setFilters(const QStringList &)
Q3FileDialog::setIconProvider(Q3FileIconProvider *)	N/A
Q3FileDialog::setInfoPreview(QWidget , Q3FilePreview )	N/A
Q3FileDialog::setInfoPreviewEnabled(bool)	N/A
Q3FileDialog::setPreviewMode(PreviewMode)	N/A
Q3FileDialog::setSelectedFilter(const QString &)	QFileDialog::selectFilter(const QString &)
Q3FileDialog::setSelectedFilter(int)	See remark below
Q3FileDialog::setSelection(const QString &)	QFileDialog::selectFile(const QString &)
Q3FileDialog::setShowHiddenFiles(bool)	showHidden()
Q3FileDialog::setUrl(const QUrlOperator &)	N/A
Q3FileDialog::showHiddenFiles()	N/A
Q3FileDialog::url()	QUrl::fromLocalFile(QFileDialog::directory())
Old signals	Qt 4 equivalent
Q3FileDialog::fileHighlighted(const QString &)	N/A
Q3FileDialog::fileSelected(const QString &)	QFileDialog::filesSelected(const QStringList &)
Q3FileDialog::dirEntered(const QString &)	N/A
Q3FileDialog::filterSelected(const QString &)	N/A

Qt 3 function	Qt 4 equivalents
QImageIO::description()	QImageWriter::text()
QImageIO::fileName()	QImageReader::fileName() and QImageWriter::fileName()
QImageIO::format()	QImageReader::format() and QImageWriter::format()
QImageIO::gamma()	QImageWriter::gamma()
QImageIO::image()	Return value of QImageReader::read()
QImageIO::inputFormats()	QImageReader::supportedImageFormats()
QImageIO::ioDevice()	QImageReader::device() and QImageWriter::device()
QImageIO::outputFormats()	QImageWriter::supportedImageFormats()
QImageIO::parameters()	N/A
QImageIO::quality()	QImageWriter::quality()
QImageIO::read()	QImageReader::read()
QImageIO::setDescription()	QImageWriter::setText()
QImageIO::setFileName()	QImageReader::setFileName() and QImageWriter::setFileName()
QImageIO::setFormat()	QImageReader::setFormat() and QImageWriter::setFormat()
QImageIO::setGamma()	QImageWriter::setGamma()
QImageIO::setIODevice()	QImageReader::setDevice() and QImageWriter::setDevice()
QImageIO::setImage()	Argument to QImageWriter::write()
QImageIO::setParameters()	N/A
QImageIO::setQuality()	QImageWriter::setQuality()
QImageIO::setStatus()	N/A
QImageIO::status()	QImageReader::error() and QImageWriter::error()
QImageIO::write()	QImageWriter::write()

Qt 3 function	Comment
QIODevice::at() const	Renamed QIODevice::pos().
QIODevice::at(Offset)	Renamed QIODevice::seek().
QIODevice::open(int)	The parameter is now of type QIODevice::OpenMode.
QIODevice::readBlock(char *, Q_ULONG)	QIODevice::read(char *, qint64)
QIODevice::writeBlock(const char *, Q_ULONG)	QIODevice::write(const char *, qint64)

QIODevice::getch()	Renamed QIODevice::getChar() and implemented in terms of QIODevice::readData().
QIODevice::putch(int)	Renamed QIODevice::putChar() and implemented in terms of QIODevice::writeData().
QIODevice::readAll()	Implemented in terms of QIODevice::readData().
QIODevice::readLine(char *, Q_ULONG)	Implemented in terms of QIODevice::readData()
QIODevice::ungetch(int)	Renamed QIODevice::ungetChar() and simulated using an internal unget buffer.

Qt 3 constant	Qt 4 equivalent
IO_Direct	Use !QIODevice::isSequential() instead (notice the not).
IO_Sequential	Use QIODevice::isSequential() instead.
IO_Combined	N/A
IO_TypeMask	N/A
IO_Raw	QIODevice::Unbuffered
IO_Async	N/A
IO_ReadOnly	QIODevice::ReadOnly
IO_WriteOnly	QIODevice::WriteOnly
IO_ReadWrite	QIODevice::ReadWrite
IO_Append	QIODevice::Append
IO_Truncate	QIODevice::Truncate
IO_Translate	QIODevice::Text
IO_ModeMask	N/A
IO_Open	Use QIODevice::isOpen() instead.
IO_StateMask	N/A
IO_Ok	N/A
IO_ReadError	N/A
IO_WriteError	N/A
IO_FatalError	N/A
IO_ResourceError	N/A
IO_OpenError	N/A
IO_ConnectError	N/A
IO_AbortError	N/A
IO_TimeOutError	N/A
IO_UnspecifiedError	N/A

QMemArray::assign(const QMemArray<T> &)	QVector::operator=()
QMemArray::assign(const T *, uint)	See remark below
QMemArray::duplicate(const QMemArray &)	QVector::operator=()
QMemArray::duplicate(const T *, uint)	See remark below
QMemArray::setRawData(const T *, uint)	N/A
QMemArray::resetRawData(const T *, uint)	N/A
QMemArray::find(const T &, uint)	QVector::indexOf(const T &, int)
QMemArray::contains(const T &)	QVector::count(const T &)
QMemArray::sort()	qSort()
QMemArray::bsearch(const T &d)	qBinaryFind()
QMemArray::at(uint)	QVector::operator[]()
QMemArray::operator const T *()	QVector::constData()

Qt 3 function	Qt 4 equivalent
QMovie::connectResize()	Connect to QMovie::resized()
QMovie::connectStatus()	Connect to QMovie::stateChanged()
QMovie::connectUpdate()	Connect to QMovie::updated()
QMovie::disconnectResize()	Disconnect from QMovie::resized()
QMovie::disconnectStatus()	Disconnect from QMovie::stateChanged()
QMovie::disconnectUpdate()	Disconnect from QMovie::updated()
QMovie::finished()	Use QMovie::state() instead
QMovie::frameImage()	Use QMovie::currentImage() instead
QMovie::frameNumber()	Use QMovie::currentFrameNumber() instead
QMovie::framePixmap()	Use QMovie::currentPixmap() instead
QMovie::getValidRect()	Use frameRect() instead
QMovie::isNull()	Use QMovie::isValid() instead
QMovie::pause()	Use QMovie::setPaused(true) instead
QMovie::paused()	Use QMovie::state() instead
QMovie::pushData()	N/A
QMovie::pushSpace()	N/A
QMovie::restart()	Use QMovie::jumpToFrame(0) instead
QMovie::running()	Use QMovie::state() instead
QMovie::step()	Use QMovie::jumpToFrame() and QMovie::setPaused() instead
QMovie::step()	Use QMovie::jumpToNextFrame() instead
QMovie::steps()	Use QMovie::currentFrameNumber() and QMovie::frameCount() instead
QMovie::unpause()	Use QMovie::setPaused(false) instead

QPtrList function	QList equivalent
QPtrList::contains(const T *)	QList::count(T *)
QPtrList::containsRef(const T *)	QList::count(T *)
QPtrList::find(const T *)	See remark below
QPtrList::findRef(const T *)	See remark below
QPtrList::getFirst()	QList::first()
QPtrList::getLast()	QList::last()
QPtrList::inSort(const T *)	N/A
QPtrList::remove(const T *)	QList::removeAll(T *)
QPtrList::remove(uint)	QList::removeAt(int)
QPtrList::removeNode(QLNode *)	N/A
QPtrList::removeRef(const T *)	QList::removeAll(T *)
QPtrList::sort()	See remark below
QPtrList::takeNode(QLNode *)	N/A
QPtrList::toVector(QGVector *)	See remark below

QPtrList idiom	QList idiom
list.replace(index, value);	delete list[index]; list[index] = value;
list.removeFirst();	delete list.takeFirst();
list.removeLast();	delete list.takeLast();
list.remove(index);	delete list.takeAt(index);
list.remove(value);	int i = list.indexOf(value); if (i != -1) delete list.takeAt(i);
list.remove(); (removes the current item)	QMutableListIterator<T *> i; ... delete i.value(); i.remove();
list.clear(); (also called from QPtrList's destructor)	while (!list.isEmpty()) delete list.takeFirst(); In 99% of cases, the following idiom also works: qDeleteAll(list); list.clear(); However, it may lead to crashes if `list` is referenced from the value type's destructor, because `list` contains dangling pointers until clear() is called.

QPtrList function	QListIterator equivalent
QPtrList::at()	N/A
QPtrList::current()	QMutableListIterator::value()
QPtrList::currentNode()	N/A
QPtrList::findNext(const T *)	QListIterator::findNext(const T *)
QPtrList::findNextRef(const T *)	QListIterator::findNext(const T *)
QPtrList::first()	QPtrList::toFront()
QPtrList::last()	QPtrList::toBack()
QPtrList::next()	QPtrList::next()
QPtrList::prev()	QPtrList::previous()
QPtrList::remove()	QMutableListIterator::remove()
QPtrList::take()	QMutableListIterator::remove()

Qt Documentation

Contents

Porting to Qt 4

Casting and Object Types

Type Names

Enum Values

Properties

Explicit Sharing

Painting and Redrawing Widgets

Compatibility Signals and Slots

QAccel

QAccessibleInterface

QAccessibleTitleBar

QAction

QActionGroup

QApplication

QAquaStyle

QAsciiCache<T>

QAsciiDict<T>

QAsyncIO

QBackInsertIterator

QBitArray

QButton

QButtonGroup

QByteArray

QCache<T>

QCanvas

QColor

QColorGroup

QColorDrag

QComboBox

QCString

QCustomEvent

QDataBrowser

QDataPump

QDataSink

QDataSource

QDataTable

QDataView

QDateEdit

QDateTimeEditBase

QDateTimeEdit

QDeepCopy<T>

QDial

QDict<T>

QDir

QDns

QDockArea

QDockWindow

QDragObject

QDropSite

QEditorFactory

QEventLoop

QFileDialog

QFocusData

QFocusEvent

QFont

QFrame

QFtp

QGLayoutIterator

QGrid

QGridLayout

QGridView

QGroupBox

QHBox

QHeader

QHGroupBox

QHttp

QIconFactory

QIconSet

QIconView

QImageDrag

QImageIO

QIntCache<T>

QIntDict<T>

QIODevice

QIODeviceSource

QLabel

QLayout

QLayoutIterator

QPtrListIterator function	Qt 4 equivalent
QPtrListIterator::atFirst()	!QListIterator::hasPrevious() (notice the `!`)
QPtrListIterator::atLast()	!QListIterator::hasNext() (notice the `!`)
QPtrListIterator::count()	QList::count() or QList::size()
QPtrListIterator::current()	QMutableListIterator::value()
QPtrListIterator::isEmpty()	QList::isEmpty()
QPtrListIterator::toFirst()	QListIterator::toFront()
QPtrListIterator::toLast()	QListIterator::toBack()
QPtrListIterator::operator()	QMutableListIterator::value()
QPtrListIterator::operator*()	QMutableListIterator::value()

QPtrQueue function	QQueue equivalent
QPtrQueue::autoDelete()	See discussion below
QPtrQueue::count()	QQueue::count() or QQueue::size() (equivalent)
QPtrQueue::current()	QQueue::head()
QPtrQueue::remove()	QQueue::dequeue()
QPtrQueue::setAutoDelete()	See discussion below

QPtrStack function	QStack equivalent
QPtrStack::autoDelete()	See discussion below
QPtrStack::count()	QStack::count() or QStack::size() (equivalent)
QPtrStack::current()	QStack::top()
QPtrStack::remove()	QStack::pop()
QPtrStack::setAutoDelete()	See discussion below

QPtrVector function	QVector equivalent
QPtrVector::autoDelete()	See discussion below
QPtrVector::bsearch(const T *)	qBinaryFind()
QPtrVector::contains(const T *)	QVector::count(T *)
QPtrVector::containsRef(const T *)	QVector::count(T *)
QPtrVector::count()	See remark below
QPtrVector::insert(uint, T *)	See remark below
QPtrVector::isNull()	N/A
QPtrVector::remove(uint)	See remark below
QPtrVector::setAutoDelete()	See discussion below
QPtrVector::sort()	qSort()
QPtrVector::take(uint)	See remark below
QPtrVector::toList(QGList *)	QList::QList(const QVector &)

QPtrVector idiom	QVector idiom
vect.insert(i, ptr);	delete vect[i]; vect[i] = ptr;
vect.remove(i);	delete vect[i]; vect[i] = 0;
T *ptr = vect.take(i);	T *ptr = vect[i]; vect[i] = 0;
vect.resize(n)	while (n > vect.size()) vect.append(0); while (n < vect.size() { T *ptr = vect.last(); vect.remove(vect.size() - 1); delete ptr; }
vect.clear(); (also called from QPtrVector's destructor)	for (int i = 0; i < vect.size(); ++i) T *ptr = vect[i]; vect[i] = 0; delete ptr; } In 99% of cases, the following idiom also works: qDeleteAll(vect); vect.clear(); However, it may lead to crashes if `vect` is referenced from the value type's destructor, because `vect` contains dangling pointers until clear() is called.

Old name	New name	Remark
`PE_ButtonCommand`	QStyle::PE_PanelButtonCommand
`PE_ButtonDefault`	QStyle::PE_FrameDefaultButton
`PE_ButtonBevel`	QStyle::PE_PanelButtonBevel
`PE_ButtonTool`	QStyle::PE_PanelButtonTool
`PE_ButtonDropDown`	QStyle::PE_IndicatorButtonDropDown
`PE_FocusRect`	QStyle::PE_FrameFocusRect
`PE_ArrowUp`	QStyle::PE_IndicatorArrowUp
`PE_ArrowDown`	QStyle::PE_IndicatorArrowDown
`PE_ArrowRight`	QStyle::PE_IndicatorArrowRight
`PE_ArrowLeft`	QStyle::PE_IndicatorArrowLeft
`PE_SpinBoxUp`	QStyle::PE_IndicatorSpinUp
`PE_SpinBoxDown`	QStyle::PE_IndicatorSpinDown
`PE_SpinBoxPlus`	QStyle::PE_IndicatorSpinPlus
`PE_SpinBoxMinus`	QStyle::PE_IndicatorSpinMinus
`PE_SpinBoxSlider`	QStyle::CE_SpinBoxSlider	uses QStyle::drawControl()
`PE_Indicator`	QStyle::PE_IndicatorCheckBox
`PE_IndicatorMask`	N/A	use QStyle::styleHint() to retrieve mask
`PE_ExclusiveIndicator`	QStyle::PE_IndicatorRadioButton
`PE_ExclusiveIndicatorMask`	N/A	use QStyle::styleHint() to retrieve mask
`PE_DockWindowHandle`	QStyle::PE_IndicatorToolBarHandle
`PE_DockWindowSeparator`	QStyle::PE_Q3DockWindowSeparator
`PE_DockWindowResizeHandle`	QStyle::PE_IndicatorDockWindowResizeHandle
`PE_DockWindowTitle`	QStyle::CE_DockWindowTitle	uses QStyle::drawControl()
`PE_Splitter`	QStyle::CE_Splitter	uses QStyle::drawControl()
`PE_Panel`	QStyle::PE_Frame
`PE_PanelMenu`	QStyle::PE_FrameMenu
`PE_PanelMenuBar`	QStyle::PE_PanelMenuBar
`PE_PanelDockWindow`	QStyle::PE_FrameDockWindow
`PE_TabBarBase`	QStyle::PE_FrameTabBarBase
`PE_HeaderSection`	QStyle::CE_HeaderSection	uses QStyle::drawControl()
`PE_HeaderArrow`	QStyle::PE_IndicatorHeaderArrow
`PE_StatusBarSection`	QStyle::PE_FrameStatusBar
`PE_Separator`	QStyle::PE_Q3Separator
`PE_SizeGrip`	QStyle::CE_SizeGrip	uses QStyle::drawControl()
`PE_CheckMark`	QStyle::PE_IndicatorMenuCheckMark
`PE_ScrollBarAddLine`	QStyle::CE_ScrollBarAddLine	uses QStyle::drawControl()
`PE_ScrollBarSubLine`	QStyle::CE_ScrollBarSubLine	uses QStyle::drawControl()
`PE_ScrollBarAddPage`	QStyle::CE_ScrollBarAddPage	uses QStyle::drawControl()
`PE_ScrollBarSubPage`	QStyle::CE_ScrollBarSubPage	uses QStyle::drawControl()
`PE_ScrollBarSlider`	QStyle::CE_ScrollBarSlider	uses QStyle::drawControl()
`PE_ScrollBarFirst`	QStyle::CE_ScrollBarFirst	uses QStyle::drawControl()
`PE_ScrollBarLast`	QStyle::CE_ScrollBarLast	uses QStyle::drawControl()
`PE_ProgressBarChunk`	QStyle::PE_IndicatorProgressChunk
`PE_PanelLineEdit`	QStyle::PE_FrameLineEdit
`PE_PanelTabWidget`	QStyle::PE_FrameTabWidget
`PE_WindowFrame`	QStyle::PE_FrameWindow
`PE_CheckListController`	QStyle::PE_Q3CheckListController
`PE_CheckListIndicator`	QStyle::PE_Q3CheckListIndicator
`PE_CheckListExclusiveIndicator`	QStyle::PE_Q3CheckListExclusiveIndicator
`PE_PanelGroupBox`	QStyle::PE_FrameGroupBox
`PE_TreeBranch`	QStyle::PE_IndicatorBranch
`PE_RubberBand`	QStyle::CE_RubberBand	uses QStyle::drawControl()
`PE_PanelToolBar`	QStyle::PE_PanelToolBar
`PE_ToolBarHandle`	QStyle::PE_IndicatorToolBarHandle
`PE_ToolBarSeparator`	QStyle::PE_IndicatorToolBarSeparator

Qt 3 function	Qt 4 function
toBitmap ()	QVariant::value()
toBrush ()	QVariant::value()
toColorGroup ()	Use QVariant::value() with QPalette instead.
toColor ()	QVariant::value()
toCString ()	QVariant::toByteArray()
toCursor ()	QVariant::value()
toFont ()	QVariant::value()
toIconSet ()	Use QVariant::value() with QIcon instead.
toImage ()	QVariant::value()
toKeySequence ()	QVariant::value()
toPalette ()	QVariant::value()
toPen ()	QVariant::value()
toPixmap ()	QVariant::value()
toPointArray ()	QVariant::value()
toRegion ()	QVariant::value()
toSizePolicy ()	QVariant::value()