QAbstractSpinBox Class

The QAbstractSpinBox class provides a spinbox and a line edit to display values. More...

• List of all members, including inherited members

Public Types

Properties

Public Functions

Reimplemented Public Functions

Public Slots

Signals

Protected Functions

Reimplemented Protected Functions

Detailed Description

The class is designed as a common super class for widgets like QSpinBox, QDoubleSpinBox and QDateTimeEdit

Here are the main properties of the class:

1. text: The text that is displayed in the QAbstractSpinBox.
2. alignment: The alignment of the text in the QAbstractSpinBox.
3. wrapping: Whether the QAbstractSpinBox wraps from the minimum value to the maximum value and vice versa.

QAbstractSpinBox provides a virtual stepBy() function that is called whenever the user triggers a step. This function takes an integer value to signify how many steps were taken. E.g. Pressing Qt::Key_Down will trigger a call to stepBy(-1).

When the user triggers a step whilst holding the Qt::ControlModifier, QAbstractSpinBox steps by 10 instead of making a single step. This step modifier affects wheel events, key events and interaction with the spinbox buttons. Note that on macOS, Control corresponds to the Command key.

Since Qt 5.12, QStyle::SH_SpinBox_StepModifier can be used to select which Qt::KeyboardModifier increases the step rate. Qt::NoModifier disables this feature.

QAbstractSpinBox also provide a virtual function stepEnabled() to determine whether stepping up/down is allowed at any point. This function returns a bitset of StepEnabled.

See also QAbstractSlider, QSpinBox, QDoubleSpinBox, QDateTimeEdit, and Spin Boxes Example.

Member Type Documentation

enum QAbstractSpinBox::ButtonSymbols

This enum type describes the symbols that can be displayed on the buttons in a spin box.

See also QAbstractSpinBox::buttonSymbols.

enum QAbstractSpinBox::CorrectionMode

This enum type describes the mode the spinbox will use to correct an Intermediate value if editing finishes.

See also correctionMode.

enum QAbstractSpinBox::StepEnabledFlagflags QAbstractSpinBox::StepEnabled

The StepEnabled type is a typedef for QFlags<StepEnabledFlag>. It stores an OR combination of StepEnabledFlag values.

enum QAbstractSpinBox::StepType

    QSpinBox *zoomSpinBox = new QSpinBox;
    zoomSpinBox->setRange(0, 1000);
    zoomSpinBox->setSingleStep(10);
    zoomSpinBox->setSuffix("%");
    zoomSpinBox->setSpecialValueText(tr("Automatic"));
    zoomSpinBox->setValue(100);

QSpinBox *spinBox = new QSpinBox(this);
spinBox->setRange(0, 100);
spinBox->setWrapping(true);
spinBox->setValue(100);
spinBox->stepBy(1);
// value is 0

Member Function Documentation

QAbstractSpinBox::QAbstractSpinBox(QWidget *parent = nullptr)

Constructs an abstract spinbox with the given parent with default wrapping, and alignment properties.

[virtual slot] void QAbstractSpinBox::clear()

Clears the lineedit of all text but prefix and suffix.

[signal] void QAbstractSpinBox::editingFinished()

This signal is emitted editing is finished. This happens when the spinbox loses focus and when enter is pressed.

[slot] void QAbstractSpinBox::selectAll()

Selects all the text in the spinbox except the prefix and suffix.

[slot] void QAbstractSpinBox::stepDown()

Steps down by one linestep Calling this slot is analogous to calling stepBy(-1);

See also stepBy() and stepUp().

[slot] void QAbstractSpinBox::stepUp()

Steps up by one linestep Calling this slot is analogous to calling stepBy(1);

See also stepBy() and stepDown().

[virtual] QAbstractSpinBox::~QAbstractSpinBox()

Called when the QAbstractSpinBox is destroyed.

[override virtual protected] void QAbstractSpinBox::changeEvent(QEvent *event)

Reimplements: QWidget::changeEvent(QEvent *event).

[override virtual protected] void QAbstractSpinBox::closeEvent(QCloseEvent *event)

Reimplements: QWidget::closeEvent(QCloseEvent *event).

[override virtual protected] void QAbstractSpinBox::contextMenuEvent(QContextMenuEvent *event)

Reimplements: QWidget::contextMenuEvent(QContextMenuEvent *event).

[override virtual] bool QAbstractSpinBox::event(QEvent *event)

Reimplements: QWidget::event(QEvent *event).

[virtual] void QAbstractSpinBox::fixup(QString &input) const

This virtual function is called by the QAbstractSpinBox if the input is not validated to QValidator::Acceptable when Return is pressed or interpretText() is called. It will try to change the text so it is valid. Reimplemented in the various subclasses.

[override virtual protected] void QAbstractSpinBox::focusInEvent(QFocusEvent *event)

Reimplements: QWidget::focusInEvent(QFocusEvent *event).

[override virtual protected] void QAbstractSpinBox::focusOutEvent(QFocusEvent *event)

Reimplements: QWidget::focusOutEvent(QFocusEvent *event).

[override virtual protected] void QAbstractSpinBox::hideEvent(QHideEvent *event)

Reimplements: QWidget::hideEvent(QHideEvent *event).

[protected] void QAbstractSpinBox::initStyleOption(QStyleOptionSpinBox *option) const

Initialize option with the values from this QSpinBox. This method is useful for subclasses when they need a QStyleOptionSpinBox, but don't want to fill in all the information themselves.

See also QStyleOption::initFrom().

[override virtual] QVariant QAbstractSpinBox::inputMethodQuery(Qt::InputMethodQuery query) const

Reimplements: QWidget::inputMethodQuery(Qt::InputMethodQuery query) const.

void QAbstractSpinBox::interpretText()

This function interprets the text of the spin box. If the value has changed since last interpretation it will emit signals.

[override virtual protected] void QAbstractSpinBox::keyPressEvent(QKeyEvent *event)

Reimplements: QWidget::keyPressEvent(QKeyEvent *event).

This function handles keyboard input.

The following keys are handled specifically:

See also stepBy().

[override virtual protected] void QAbstractSpinBox::keyReleaseEvent(QKeyEvent *event)

Reimplements: QWidget::keyReleaseEvent(QKeyEvent *event).

[protected] QLineEdit *QAbstractSpinBox::lineEdit() const

This function returns a pointer to the line edit of the spin box.

See also setLineEdit().

[override virtual] QSize QAbstractSpinBox::minimumSizeHint() const

Reimplements an access function for property: QWidget::minimumSizeHint.

[override virtual protected] void QAbstractSpinBox::mouseMoveEvent(QMouseEvent *event)

Reimplements: QWidget::mouseMoveEvent(QMouseEvent *event).

[override virtual protected] void QAbstractSpinBox::mousePressEvent(QMouseEvent *event)

Reimplements: QWidget::mousePressEvent(QMouseEvent *event).

[override virtual protected] void QAbstractSpinBox::mouseReleaseEvent(QMouseEvent *event)

Reimplements: QWidget::mouseReleaseEvent(QMouseEvent *event).

[override virtual protected] void QAbstractSpinBox::paintEvent(QPaintEvent *event)

Reimplements: QWidget::paintEvent(QPaintEvent *event).

[override virtual protected] void QAbstractSpinBox::resizeEvent(QResizeEvent *event)

Reimplements: QWidget::resizeEvent(QResizeEvent *event).

[protected] void QAbstractSpinBox::setLineEdit(QLineEdit *lineEdit)

Sets the line edit of the spinbox to be lineEdit instead of the current line edit widget. lineEdit cannot be nullptr.

QAbstractSpinBox takes ownership of the new lineEdit

If QLineEdit::validator() for the lineEdit returns nullptr, the internal validator of the spinbox will be set on the line edit.

See also lineEdit().

[override virtual protected] void QAbstractSpinBox::showEvent(QShowEvent *event)

Reimplements: QWidget::showEvent(QShowEvent *event).

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

Reimplements an access function for property: QWidget::sizeHint.

[virtual] void QAbstractSpinBox::stepBy(int steps)

Virtual function that is called whenever the user triggers a step. The steps parameter indicates how many steps were taken. For example, pressing Qt::Key_Down will trigger a call to stepBy(-1), whereas pressing Qt::Key_PageUp will trigger a call to stepBy(10).

If you subclass QAbstractSpinBox you must reimplement this function. Note that this function is called even if the resulting value will be outside the bounds of minimum and maximum. It's this function's job to handle these situations.

See also stepUp(), stepDown(), and keyPressEvent().

[virtual protected] QAbstractSpinBox::StepEnabled QAbstractSpinBox::stepEnabled() const

Virtual function that determines whether stepping up and down is legal at any given time.

The up arrow will be painted as disabled unless (stepEnabled() & StepUpEnabled) != 0.

The default implementation will return (StepUpEnabled| StepDownEnabled) if wrapping is turned on. Else it will return StepDownEnabled if value is > minimum() or'ed with StepUpEnabled if value < maximum().

If you subclass QAbstractSpinBox you will need to reimplement this function.

See also QSpinBox::minimum(), QSpinBox::maximum(), and wrapping().

[override virtual protected] void QAbstractSpinBox::timerEvent(QTimerEvent *event)

Reimplements: QObject::timerEvent(QTimerEvent *event).

[virtual] QValidator::State QAbstractSpinBox::validate(QString &input, int &pos) const

This virtual function is called by the QAbstractSpinBox to determine whether input is valid. The pos parameter indicates the position in the string. Reimplemented in the various subclasses.

[override virtual protected] void QAbstractSpinBox::wheelEvent(QWheelEvent *event)

Reimplements: QWidget::wheelEvent(QWheelEvent *event).