Struct qt_widgets::QStyleOption

#[repr(C)]pub struct QStyleOption { /* fields omitted */ }

The QStyleOption class stores the parameters used by QStyle functions.

C++ class: QStyleOption.

C++ documentation:

The QStyleOption class stores the parameters used by QStyle functions.

QStyleOption and its subclasses contain all the information that QStyle functions need to draw a graphical element.

For performance reasons, there are few member functions and the access to the member variables is direct (i.e., using the . or -> operator). This low-level feel makes the structures straightforward to use and emphasizes that these are simply parameters used by the style functions.

The caller of a QStyle function usually creates QStyleOption objects on the stack. This combined with Qt's extensive use of implicit sharing for types such as QString, QPalette, and QColor ensures that no memory allocation needlessly takes place.

The following code snippet shows how to use a specific QStyleOption subclass to paint a push button:

void MyPushButton::paintEvent(QPaintEvent *)
{
      QStyleOptionButton option;
      option.initFrom(this);
      option.state = isDown() ? QStyle::State_Sunken : QStyle::State_Raised;
      if (isDefault())
          option.features |= QStyleOptionButton::DefaultButton;
      option.text = text();
      option.icon = icon();
      QPainter painter(this);
      style()->drawControl(QStyle::CE_PushButton, &option, &painter, this);
}

In our example, the control is a QStyle::CE_PushButton, and according to the QStyle::drawControl() documentation the corresponding class is QStyleOptionButton.

When reimplementing QStyle functions that take a QStyleOption parameter, you often need to cast the QStyleOption to a subclass. For safety, you can use qstyleoption_cast() to ensure that the pointer type is correct. For example:

void MyStyle::drawPrimitive(PrimitiveElement element,
                              const QStyleOption option,
                              QPainter painter,
                              const QWidget widget)
{
      if (element == PE_FrameFocusRect) {
          const QStyleOptionFocusRect focusRectOption =
                  qstyleoption_cast<const QStyleOptionFocusRect *>(option);
          if (focusRectOption) {
              // ...
          }
      }
      // ...
}

The qstyleoption_cast() function will return 0 if the object to which option points is not of the correct type.

For an example demonstrating how style options can be used, see the Styles example.

Methods

impl QStyleOption

pub unsafe fn copy_from(
    &self,
    other: impl CastInto<Ref<QStyleOption>>
) -> Ref<QStyleOption>

Assign other to this QStyleOption.

Calls C++ function: QStyleOption& QStyleOption::operator=(const QStyleOption& other).

C++ documentation:

Assign other to this QStyleOption.

pub unsafe fn direction(&self) -> LayoutDirection

Returns the value of the direction field.

pub unsafe fn font_metrics(&self) -> Ref<QFontMetrics>

Returns a reference to the fontMetrics field.

pub unsafe fn font_metrics_mut(&self) -> Ref<QFontMetrics>

Returns a mutable reference to the fontMetrics field.

pub unsafe fn init(&self, w: impl CastInto<Ptr<QWidget>>)

Use initFrom(widget) instead.

Calls C++ function: void QStyleOption::init(const QWidget* w).

C++ documentation:

Use initFrom(widget) instead.

pub unsafe fn init_from(&self, w: impl CastInto<Ptr<QWidget>>)

Initializes the state, direction, rect, palette, fontMetrics and styleObject member variables based on the specified widget.

Calls C++ function: void QStyleOption::initFrom(const QWidget* w).

C++ documentation:

Initializes the state, direction, rect, palette, fontMetrics and styleObject member variables based on the specified widget.

This is a convenience function; the member variables can also be initialized manually.

This function was introduced in Qt 4.1.

See also QWidget::layoutDirection(), QWidget::rect(), QWidget::palette(), and QWidget::fontMetrics().

pub unsafe fn new_2a(version: c_int, type_: c_int) -> CppBox<QStyleOption>

Constructs a QStyleOption with the specified version and type.

Calls C++ function: [constructor] void QStyleOption::QStyleOption(int version = …, int type = …).

C++ documentation:

Constructs a QStyleOption with the specified version and type.

The version has no special meaning for QStyleOption; it can be used by subclasses to distinguish between different version of the same option type.

The state member variable is initialized to QStyle::State_None.

See also version and type.

pub unsafe fn new_0a() -> CppBox<QStyleOption>

The QStyleOption class stores the parameters used by QStyle functions.

Calls C++ function: [constructor] void QStyleOption::QStyleOption().

C++ documentation:

The QStyleOption class stores the parameters used by QStyle functions.

QStyleOption and its subclasses contain all the information that QStyle functions need to draw a graphical element.

For performance reasons, there are few member functions and the access to the member variables is direct (i.e., using the . or -> operator). This low-level feel makes the structures straightforward to use and emphasizes that these are simply parameters used by the style functions.

The caller of a QStyle function usually creates QStyleOption objects on the stack. This combined with Qt's extensive use of implicit sharing for types such as QString, QPalette, and QColor ensures that no memory allocation needlessly takes place.

The following code snippet shows how to use a specific QStyleOption subclass to paint a push button:

void MyPushButton::paintEvent(QPaintEvent *)
{
      QStyleOptionButton option;
      option.initFrom(this);
      option.state = isDown() ? QStyle::State_Sunken : QStyle::State_Raised;
      if (isDefault())
          option.features |= QStyleOptionButton::DefaultButton;
      option.text = text();
      option.icon = icon();
      QPainter painter(this);
      style()->drawControl(QStyle::CE_PushButton, &option, &painter, this);
}

In our example, the control is a QStyle::CE_PushButton, and according to the QStyle::drawControl() documentation the corresponding class is QStyleOptionButton.

When reimplementing QStyle functions that take a QStyleOption parameter, you often need to cast the QStyleOption to a subclass. For safety, you can use qstyleoption_cast() to ensure that the pointer type is correct. For example:

void MyStyle::drawPrimitive(PrimitiveElement element,
                              const QStyleOption option,
                              QPainter painter,
                              const QWidget widget)
{
      if (element == PE_FrameFocusRect) {
          const QStyleOptionFocusRect focusRectOption =
                  qstyleoption_cast<const QStyleOptionFocusRect *>(option);
          if (focusRectOption) {
              // ...
          }
      }
      // ...
}

The qstyleoption_cast() function will return 0 if the object to which option points is not of the correct type.

For an example demonstrating how style options can be used, see the Styles example.

pub unsafe fn new_1a(version: c_int) -> CppBox<QStyleOption>

Constructs a QStyleOption with the specified version and type.

Calls C++ function: [constructor] void QStyleOption::QStyleOption(int version = …).

C++ documentation:

Constructs a QStyleOption with the specified version and type.

The version has no special meaning for QStyleOption; it can be used by subclasses to distinguish between different version of the same option type.

The state member variable is initialized to QStyle::State_None.

See also version and type.

pub unsafe fn new_copy(
    other: impl CastInto<Ref<QStyleOption>>
) -> CppBox<QStyleOption>

Constructs a copy of other.

Calls C++ function: [constructor] void QStyleOption::QStyleOption(const QStyleOption& other).

C++ documentation:

Constructs a copy of other.

pub unsafe fn palette(&self) -> Ref<QPalette>

Returns a reference to the palette field.

pub unsafe fn palette_mut(&self) -> Ref<QPalette>

Returns a mutable reference to the palette field.

pub unsafe fn rect(&self) -> Ref<QRect>

Returns a reference to the rect field.

pub unsafe fn rect_mut(&self) -> Ref<QRect>

Returns a mutable reference to the rect field.

pub unsafe fn set_direction(&self, value: LayoutDirection)

Sets the value of the direction field.

pub unsafe fn set_font_metrics(&self, value: impl CastInto<Ref<QFontMetrics>>)

Sets the value of the fontMetrics field.

pub unsafe fn set_palette(&self, value: impl CastInto<Ref<QPalette>>)

Sets the value of the palette field.

pub unsafe fn set_rect(&self, value: impl CastInto<Ref<QRect>>)

Sets the value of the rect field.

pub unsafe fn set_state(&self, value: QFlags<StateFlag>)

Sets the value of the state field.

pub unsafe fn set_style_object(&self, value: impl CastInto<Ptr<QObject>>)

Sets the value of the styleObject field.

pub unsafe fn set_type(&self, value: c_int)

Sets the value of the type field.

pub unsafe fn set_version(&self, value: c_int)

Sets the value of the version field.

pub unsafe fn state(&self) -> QFlags<StateFlag>

Returns a reference to the state field.

pub unsafe fn style_object(&self) -> QPtr<QObject>

Returns the value of the styleObject field.

pub unsafe fn type_(&self) -> c_int

Returns the value of the type field.

pub unsafe fn version(&self) -> c_int

Returns the value of the version field.

Trait Implementations

impl CppDeletable for QStyleOption

unsafe fn delete(&self)

Destroys this style option object.

Calls C++ function: [destructor] void QStyleOption::~QStyleOption().

C++ documentation:

Destroys this style option object.

impl StaticDowncast<QStyleOptionButton> for QStyleOption

unsafe fn static_downcast(ptr: Ptr<QStyleOption>) -> Ptr<QStyleOptionButton>

Calls C++ function: QStyleOptionButton* static_cast<QStyleOptionButton*>(QStyleOption* ptr).

impl StaticDowncast<QStyleOptionComboBox> for QStyleOption

unsafe fn static_downcast(ptr: Ptr<QStyleOption>) -> Ptr<QStyleOptionComboBox>

Calls C++ function: QStyleOptionComboBox* static_cast<QStyleOptionComboBox*>(QStyleOption* ptr).

impl StaticDowncast<QStyleOptionComplex> for QStyleOption

unsafe fn static_downcast(ptr: Ptr<QStyleOption>) -> Ptr<QStyleOptionComplex>

Calls C++ function: QStyleOptionComplex* static_cast<QStyleOptionComplex*>(QStyleOption* ptr).

impl StaticDowncast<QStyleOptionDockWidget> for QStyleOption

unsafe fn static_downcast(ptr: Ptr<QStyleOption>) -> Ptr<QStyleOptionDockWidget>

Calls C++ function: QStyleOptionDockWidget* static_cast<QStyleOptionDockWidget*>(QStyleOption* ptr).

impl StaticDowncast<QStyleOptionFocusRect> for QStyleOption

unsafe fn static_downcast(ptr: Ptr<QStyleOption>) -> Ptr<QStyleOptionFocusRect>

Calls C++ function: QStyleOptionFocusRect* static_cast<QStyleOptionFocusRect*>(QStyleOption* ptr).

impl StaticDowncast<QStyleOptionFrame> for QStyleOption

unsafe fn static_downcast(ptr: Ptr<QStyleOption>) -> Ptr<QStyleOptionFrame>

Calls C++ function: QStyleOptionFrame* static_cast<QStyleOptionFrame*>(QStyleOption* ptr).

impl StaticDowncast<QStyleOptionGraphicsItem> for QStyleOption

unsafe fn static_downcast(
    ptr: Ptr<QStyleOption>
) -> Ptr<QStyleOptionGraphicsItem>

Calls C++ function: QStyleOptionGraphicsItem* static_cast<QStyleOptionGraphicsItem*>(QStyleOption* ptr).

impl StaticDowncast<QStyleOptionGroupBox> for QStyleOption

unsafe fn static_downcast(ptr: Ptr<QStyleOption>) -> Ptr<QStyleOptionGroupBox>

Calls C++ function: QStyleOptionGroupBox* static_cast<QStyleOptionGroupBox*>(QStyleOption* ptr).

impl StaticDowncast<QStyleOptionHeader> for QStyleOption

unsafe fn static_downcast(ptr: Ptr<QStyleOption>) -> Ptr<QStyleOptionHeader>

Calls C++ function: QStyleOptionHeader* static_cast<QStyleOptionHeader*>(QStyleOption* ptr).

impl StaticDowncast<QStyleOptionMenuItem> for QStyleOption

unsafe fn static_downcast(ptr: Ptr<QStyleOption>) -> Ptr<QStyleOptionMenuItem>

Calls C++ function: QStyleOptionMenuItem* static_cast<QStyleOptionMenuItem*>(QStyleOption* ptr).

impl StaticDowncast<QStyleOptionProgressBar> for QStyleOption

unsafe fn static_downcast(
    ptr: Ptr<QStyleOption>
) -> Ptr<QStyleOptionProgressBar>

Calls C++ function: QStyleOptionProgressBar* static_cast<QStyleOptionProgressBar*>(QStyleOption* ptr).

impl StaticDowncast<QStyleOptionRubberBand> for QStyleOption

unsafe fn static_downcast(ptr: Ptr<QStyleOption>) -> Ptr<QStyleOptionRubberBand>

Calls C++ function: QStyleOptionRubberBand* static_cast<QStyleOptionRubberBand*>(QStyleOption* ptr).

impl StaticDowncast<QStyleOptionSizeGrip> for QStyleOption

unsafe fn static_downcast(ptr: Ptr<QStyleOption>) -> Ptr<QStyleOptionSizeGrip>

Calls C++ function: QStyleOptionSizeGrip* static_cast<QStyleOptionSizeGrip*>(QStyleOption* ptr).

impl StaticDowncast<QStyleOptionSlider> for QStyleOption

unsafe fn static_downcast(ptr: Ptr<QStyleOption>) -> Ptr<QStyleOptionSlider>

Calls C++ function: QStyleOptionSlider* static_cast<QStyleOptionSlider*>(QStyleOption* ptr).

impl StaticDowncast<QStyleOptionSpinBox> for QStyleOption

unsafe fn static_downcast(ptr: Ptr<QStyleOption>) -> Ptr<QStyleOptionSpinBox>

Calls C++ function: QStyleOptionSpinBox* static_cast<QStyleOptionSpinBox*>(QStyleOption* ptr).

impl StaticDowncast<QStyleOptionTab> for QStyleOption

unsafe fn static_downcast(ptr: Ptr<QStyleOption>) -> Ptr<QStyleOptionTab>

Calls C++ function: QStyleOptionTab* static_cast<QStyleOptionTab*>(QStyleOption* ptr).

impl StaticDowncast<QStyleOptionTabBarBase> for QStyleOption

unsafe fn static_downcast(ptr: Ptr<QStyleOption>) -> Ptr<QStyleOptionTabBarBase>

Calls C++ function: QStyleOptionTabBarBase* static_cast<QStyleOptionTabBarBase*>(QStyleOption* ptr).

impl StaticDowncast<QStyleOptionTabWidgetFrame> for QStyleOption

unsafe fn static_downcast(
    ptr: Ptr<QStyleOption>
) -> Ptr<QStyleOptionTabWidgetFrame>

Calls C++ function: QStyleOptionTabWidgetFrame* static_cast<QStyleOptionTabWidgetFrame*>(QStyleOption* ptr).

impl StaticDowncast<QStyleOptionTitleBar> for QStyleOption

unsafe fn static_downcast(ptr: Ptr<QStyleOption>) -> Ptr<QStyleOptionTitleBar>

Calls C++ function: QStyleOptionTitleBar* static_cast<QStyleOptionTitleBar*>(QStyleOption* ptr).

impl StaticDowncast<QStyleOptionToolBar> for QStyleOption

unsafe fn static_downcast(ptr: Ptr<QStyleOption>) -> Ptr<QStyleOptionToolBar>

Calls C++ function: QStyleOptionToolBar* static_cast<QStyleOptionToolBar*>(QStyleOption* ptr).

impl StaticDowncast<QStyleOptionToolBox> for QStyleOption

unsafe fn static_downcast(ptr: Ptr<QStyleOption>) -> Ptr<QStyleOptionToolBox>

Calls C++ function: QStyleOptionToolBox* static_cast<QStyleOptionToolBox*>(QStyleOption* ptr).

impl StaticDowncast<QStyleOptionToolButton> for QStyleOption

unsafe fn static_downcast(ptr: Ptr<QStyleOption>) -> Ptr<QStyleOptionToolButton>

Calls C++ function: QStyleOptionToolButton* static_cast<QStyleOptionToolButton*>(QStyleOption* ptr).

impl StaticDowncast<QStyleOptionViewItem> for QStyleOption

unsafe fn static_downcast(ptr: Ptr<QStyleOption>) -> Ptr<QStyleOptionViewItem>

Calls C++ function: QStyleOptionViewItem* static_cast<QStyleOptionViewItem*>(QStyleOption* ptr).

impl StaticUpcast<QStyleOption> for QStyleOptionFocusRect

unsafe fn static_upcast(ptr: Ptr<QStyleOptionFocusRect>) -> Ptr<QStyleOption>

Calls C++ function: QStyleOption* static_cast<QStyleOption*>(QStyleOptionFocusRect* ptr).

impl StaticUpcast<QStyleOption> for QStyleOptionFrame

unsafe fn static_upcast(ptr: Ptr<QStyleOptionFrame>) -> Ptr<QStyleOption>

Calls C++ function: QStyleOption* static_cast<QStyleOption*>(QStyleOptionFrame* ptr).

impl StaticUpcast<QStyleOption> for QStyleOptionDockWidget

unsafe fn static_upcast(ptr: Ptr<QStyleOptionDockWidget>) -> Ptr<QStyleOption>

Calls C++ function: QStyleOption* static_cast<QStyleOption*>(QStyleOptionDockWidget* ptr).

impl StaticUpcast<QStyleOption> for QStyleOptionViewItem

unsafe fn static_upcast(ptr: Ptr<QStyleOptionViewItem>) -> Ptr<QStyleOption>

Calls C++ function: QStyleOption* static_cast<QStyleOption*>(QStyleOptionViewItem* ptr).

impl StaticUpcast<QStyleOption> for QStyleOptionToolBox

unsafe fn static_upcast(ptr: Ptr<QStyleOptionToolBox>) -> Ptr<QStyleOption>

Calls C++ function: QStyleOption* static_cast<QStyleOption*>(QStyleOptionToolBox* ptr).

impl StaticUpcast<QStyleOption> for QStyleOptionRubberBand

unsafe fn static_upcast(ptr: Ptr<QStyleOptionRubberBand>) -> Ptr<QStyleOption>

Calls C++ function: QStyleOption* static_cast<QStyleOption*>(QStyleOptionRubberBand* ptr).

impl StaticUpcast<QStyleOption> for QStyleOptionComplex

unsafe fn static_upcast(ptr: Ptr<QStyleOptionComplex>) -> Ptr<QStyleOption>

Calls C++ function: QStyleOption* static_cast<QStyleOption*>(QStyleOptionComplex* ptr).

impl StaticUpcast<QStyleOption> for QStyleOptionSlider

unsafe fn static_upcast(ptr: Ptr<QStyleOptionSlider>) -> Ptr<QStyleOption>

Calls C++ function: QStyleOption* static_cast<QStyleOption*>(QStyleOptionSlider* ptr).

impl StaticUpcast<QStyleOption> for QStyleOptionSpinBox

unsafe fn static_upcast(ptr: Ptr<QStyleOptionSpinBox>) -> Ptr<QStyleOption>

Calls C++ function: QStyleOption* static_cast<QStyleOption*>(QStyleOptionSpinBox* ptr).

impl StaticUpcast<QStyleOption> for QStyleOptionToolButton

unsafe fn static_upcast(ptr: Ptr<QStyleOptionToolButton>) -> Ptr<QStyleOption>

Calls C++ function: QStyleOption* static_cast<QStyleOption*>(QStyleOptionToolButton* ptr).

impl StaticUpcast<QStyleOption> for QStyleOptionComboBox

unsafe fn static_upcast(ptr: Ptr<QStyleOptionComboBox>) -> Ptr<QStyleOption>

Calls C++ function: QStyleOption* static_cast<QStyleOption*>(QStyleOptionComboBox* ptr).

impl StaticUpcast<QStyleOption> for QStyleOptionTitleBar

unsafe fn static_upcast(ptr: Ptr<QStyleOptionTitleBar>) -> Ptr<QStyleOption>

Calls C++ function: QStyleOption* static_cast<QStyleOption*>(QStyleOptionTitleBar* ptr).

impl StaticUpcast<QStyleOption> for QStyleOptionTabWidgetFrame

unsafe fn static_upcast(
    ptr: Ptr<QStyleOptionTabWidgetFrame>
) -> Ptr<QStyleOption>

Calls C++ function: QStyleOption* static_cast<QStyleOption*>(QStyleOptionTabWidgetFrame* ptr).

impl StaticUpcast<QStyleOption> for QStyleOptionGroupBox

unsafe fn static_upcast(ptr: Ptr<QStyleOptionGroupBox>) -> Ptr<QStyleOption>

Calls C++ function: QStyleOption* static_cast<QStyleOption*>(QStyleOptionGroupBox* ptr).

impl StaticUpcast<QStyleOption> for QStyleOptionSizeGrip

unsafe fn static_upcast(ptr: Ptr<QStyleOptionSizeGrip>) -> Ptr<QStyleOption>

Calls C++ function: QStyleOption* static_cast<QStyleOption*>(QStyleOptionSizeGrip* ptr).

impl StaticUpcast<QStyleOption> for QStyleOptionGraphicsItem

unsafe fn static_upcast(ptr: Ptr<QStyleOptionGraphicsItem>) -> Ptr<QStyleOption>

Calls C++ function: QStyleOption* static_cast<QStyleOption*>(QStyleOptionGraphicsItem* ptr).

impl StaticUpcast<QStyleOption> for QStyleOptionTabBarBase

unsafe fn static_upcast(ptr: Ptr<QStyleOptionTabBarBase>) -> Ptr<QStyleOption>

Calls C++ function: QStyleOption* static_cast<QStyleOption*>(QStyleOptionTabBarBase* ptr).

impl StaticUpcast<QStyleOption> for QStyleOptionHeader

unsafe fn static_upcast(ptr: Ptr<QStyleOptionHeader>) -> Ptr<QStyleOption>

Calls C++ function: QStyleOption* static_cast<QStyleOption*>(QStyleOptionHeader* ptr).

impl StaticUpcast<QStyleOption> for QStyleOptionButton

unsafe fn static_upcast(ptr: Ptr<QStyleOptionButton>) -> Ptr<QStyleOption>

Calls C++ function: QStyleOption* static_cast<QStyleOption*>(QStyleOptionButton* ptr).

impl StaticUpcast<QStyleOption> for QStyleOptionTab

unsafe fn static_upcast(ptr: Ptr<QStyleOptionTab>) -> Ptr<QStyleOption>

Calls C++ function: QStyleOption* static_cast<QStyleOption*>(QStyleOptionTab* ptr).

impl StaticUpcast<QStyleOption> for QStyleOptionToolBar

unsafe fn static_upcast(ptr: Ptr<QStyleOptionToolBar>) -> Ptr<QStyleOption>

Calls C++ function: QStyleOption* static_cast<QStyleOption*>(QStyleOptionToolBar* ptr).

impl StaticUpcast<QStyleOption> for QStyleOptionProgressBar

unsafe fn static_upcast(ptr: Ptr<QStyleOptionProgressBar>) -> Ptr<QStyleOption>

Calls C++ function: QStyleOption* static_cast<QStyleOption*>(QStyleOptionProgressBar* ptr).

impl StaticUpcast<QStyleOption> for QStyleOptionMenuItem

unsafe fn static_upcast(ptr: Ptr<QStyleOptionMenuItem>) -> Ptr<QStyleOption>

Calls C++ function: QStyleOption* static_cast<QStyleOption*>(QStyleOptionMenuItem* ptr).