QWidget *firstPageWidget = new QWidget;
    QWidget *secondPageWidget = new QWidget;
    QWidget *thirdPageWidget = new QWidget;

    QStackedLayout *stackedLayout = new QStackedLayout;
    stackedLayout->addWidget(firstPageWidget);
    stackedLayout->addWidget(secondPageWidget);
    stackedLayout->addWidget(thirdPageWidget);

    QVBoxLayout *mainLayout = new QVBoxLayout;
    mainLayout->addLayout(stackedLayout);
    setLayout(mainLayout);

    QComboBox *pageComboBox = new QComboBox;
    pageComboBox->addItem(tr("Page 1"));
    pageComboBox->addItem(tr("Page 2"));
    pageComboBox->addItem(tr("Page 3"));
    connect(pageComboBox, QOverload<int>::of(&QComboBox::activated),
            stackedLayout, &QStackedLayout::setCurrentIndex);

Member Function Documentation

QStackedLayout::QStackedLayout(QLayout *parentLayout)

Constructs a new QStackedLayout and inserts it into the given parentLayout.

QStackedLayout::QStackedLayout(QWidget *parent)

Constructs a new QStackedLayout with the given parent.

This layout will install itself on the parent widget and manage the geometry of its children.

QStackedLayout::QStackedLayout()

Constructs a QStackedLayout with no parent.

This QStackedLayout must be installed on a widget later on to become effective.

See also addWidget() and insertWidget().

[signal] void QStackedLayout::currentChanged(int index)

This signal is emitted whenever the current widget in the layout changes. The index specifies the index of the new current widget, or -1 if there isn't a new one (for example, if there are no widgets in the QStackedLayout)

Note: Notifier signal for property currentIndex.

See also currentWidget() and setCurrentWidget().

[slot] void QStackedLayout::setCurrentWidget(QWidget *widget)

Sets the current widget to be the specified widget. The new current widget must already be contained in this stacked layout.

See also setCurrentIndex() and currentWidget().

[signal] void QStackedLayout::widgetRemoved(int index)

This signal is emitted whenever a widget is removed from the layout. The widget's index is passed as parameter.

See also removeWidget().

[virtual] QStackedLayout::~QStackedLayout()

Destroys this QStackedLayout. Note that the layout's widgets are not destroyed.

[override virtual] void QStackedLayout::addItem(QLayoutItem *item)

Reimplements: QLayout::addItem(QLayoutItem *item).

int QStackedLayout::addWidget(QWidget *widget)

Adds the given widget to the end of this layout and returns the index position of the widget.

If the QStackedLayout is empty before this function is called, the given widget becomes the current widget.

See also insertWidget(), removeWidget(), and setCurrentWidget().

QWidget *QStackedLayout::currentWidget() const

Returns the current widget, or nullptr if there are no widgets in this layout.

See also currentIndex() and setCurrentWidget().

[override virtual] bool QStackedLayout::hasHeightForWidth() const

Reimplements: QLayoutItem::hasHeightForWidth() const.

[override virtual] int QStackedLayout::heightForWidth(int width) const

Reimplements: QLayoutItem::heightForWidth(int ) const.

int QStackedLayout::insertWidget(int index, QWidget *widget)

Inserts the given widget at the given index in this QStackedLayout. If index is out of range, the widget is appended (in which case it is the actual index of the widget that is returned).

If the QStackedLayout is empty before this function is called, the given widget becomes the current widget.

Inserting a new widget at an index less than or equal to the current index will increment the current index, but keep the current widget.

See also addWidget(), removeWidget(), and setCurrentWidget().

[override virtual] QLayoutItem *QStackedLayout::itemAt(int index) const

Reimplements: QLayout::itemAt(int index) const.

[override virtual] QSize QStackedLayout::minimumSize() const

Reimplements: QLayout::minimumSize() const.

[override virtual] void QStackedLayout::setGeometry(const QRect &rect)

Reimplements: QLayout::setGeometry(const QRect &r).

[override virtual] QSize QStackedLayout::sizeHint() const

Reimplements: QLayoutItem::sizeHint() const.

[override virtual] QLayoutItem *QStackedLayout::takeAt(int index)

Reimplements: QLayout::takeAt(int index).

QWidget *QStackedLayout::widget(int index) const

Returns the widget at the given index, or nullptr if there is no widget at the given position.

See also currentWidget() and indexOf().