QStylePainter Class | Qt Widgets 5.14.1

Qt 5.14 | Qt Widgets | C++ Classes | QStylePainter

Qt 5.14.1 Reference Documentation

# QStylePainter Class

The QStylePainter class is a convenience class for drawing QStyle elements inside a widget. More...

Header: | #include <QStylePainter>
qmake: | QT += widgets
Inherits: | QPainter

- List of all members, including inherited members

## Public Functions

| QStylePainter(QPaintDevice *pd, QWidget *widget)
| QStylePainter(QWidget *widget)
| QStylePainter()
bool | begin(QWidget *widget)
bool | begin(QPaintDevice *pd, QWidget *widget)
void | drawComplexControl(QStyle::ComplexControl cc, const QStyleOptionComplex &option)
void | drawControl(QStyle::ControlElement ce, const QStyleOption &option)
void | drawItemPixmap(const QRect &rect, int flags, const QPixmap &pixmap)
void | drawItemText(const QRect &rect, int flags, const QPalette &pal, bool enabled, const QString &text, QPalette::ColorRole textRole = ...)
void | drawPrimitive(QStyle::PrimitiveElement pe, const QStyleOption &option)
QStyle * | style() const

## Detailed Description

QStylePainter extends QPainter with a set of high-level `draw...()` functions implemented on top of QStyle's API. The advantage of using QStylePainter is that the parameter lists get considerably shorter. Whereas a QStyle object must be able to draw on any widget using any painter (because the application normally has one QStyle object shared by all widget), a QStylePainter is initialized with a widget, eliminating the need to specify the QWidget, the QPainter, and the QStyle for every function call.

Example using QStyle directly:

      void MyWidget::paintEvent(QPaintEvent * /* event */)
      {
          QPainter painter(this);

          QStyleOptionFocusRect option;
          option.initFrom(this);
          option.backgroundColor = palette().color(QPalette::Background);

          style()->drawPrimitive(QStyle::PE_FrameFocusRect, &option, &painter, this);
      }

Example using QStylePainter:

      void MyWidget::paintEvent(QPaintEvent * /* event */)
      {
          QStylePainter painter(this);

          QStyleOptionFocusRect option;
          option.initFrom(this);
          option.backgroundColor = palette().color(QPalette::Background);

          painter.drawPrimitive(QStyle::PE_FrameFocusRect, option);
      }

See also QStyle and QStyleOption.

## Member Function Documentation

### QStylePainter::QStylePainter(QPaintDevice *pd, QWidget *widget)

Construct a QStylePainter using pd for its paint device, and attributes from widget.

### QStylePainter::QStylePainter(QWidget *widget)

Construct a QStylePainter using widget widget for its paint device.

### QStylePainter::QStylePainter()

Constructs a QStylePainter.

### bool QStylePainter::begin(QWidget *widget)

Begin painting operations on the specified widget. Returns `true` if the painter is ready to use; otherwise returns `false`.

This is automatically called by the constructor that takes a QWidget.

### bool QStylePainter::begin(QPaintDevice *pd, QWidget *widget)

This is an overloaded function.

Begin painting operations on paint device pd as if it was widget.

This is automatically called by the constructor that takes a QPaintDevice and a QWidget.

### void QStylePainter::drawComplexControl(QStyle::ComplexControl cc, const QStyleOptionComplex &option)

Use the widget's style to draw a complex control cc specified by the QStyleOptionComplex option.

See also QStyle::drawComplexControl().

### void QStylePainter::drawControl(QStyle::ControlElement ce, const QStyleOption &option)

Use the widget's style to draw a control element ce specified by QStyleOption option.

See also QStyle::drawControl().

### void QStylePainter::drawItemPixmap(const QRect &rect, int flags, const QPixmap &pixmap)

Draws the pixmap in rectangle rect. The pixmap is aligned according to flags.

See also QStyle::drawItemPixmap() and Qt::Alignment.

### void QStylePainter::drawItemText(const QRect &rect, int flags, const QPalette &pal, bool enabled, const QString &text, QPalette::ColorRole textRole = ...)

Draws the text in rectangle rect and palette pal. The text is aligned and wrapped according to flags.

The pen color is specified with textRole. The enabled bool indicates whether or not the item is enabled; when reimplementing this bool should influence how the item is drawn.

See also QStyle::drawItemText() and Qt::Alignment.

### void QStylePainter::drawPrimitive(QStyle::PrimitiveElement pe, const QStyleOption &option)

Use the widget's style to draw a primitive element pe specified by QStyleOption option.

See also QStyle::drawPrimitive().

### QStyle *QStylePainter::style() const

Return the current style used by the QStylePainter.