qstyleoption.cpp

奇趣公司比较新的qt/emd版本

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#include "qstyleoption.h"
#include "qapplication.h"
#ifdef Q_WS_MAC
# include "private/qt_mac_p.h"
# include "qmacstyle_mac.h"
#endif
#ifndef QT_NO_DEBUG
#include <qdebug.h>
#endif

/*!
    \class QStyleOption
    \brief The QStyleOption class stores the parameters used by QStyle functions.

    \ingroup appearance

    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 \c . or
    \c -> 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
    \l{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:

    \quotefromfile snippets/qstyleoption/main.cpp
    \skipto MyPushButton::paintEvent
    \printuntil /^\}/

    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:

    \quotefromfile snippets/qstyleoption/main.cpp
    \skipto MyStyle::drawPrimitive
    \printuntil /^\}/

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

    For an example demonstrating how style options can be used, see
    the \l {widgets/styles}{Styles} example.

    \sa QStyle, QStylePainter
*/

/*!
    \enum QStyleOption::OptionType

    This enum is used internally by QStyleOption, its subclasses, and
    qstyleoption_cast() to determine the type of style option. In
    general you do not need to worry about this unless you want to
    create your own QStyleOption subclass and your own styles.

    \value SO_Button \l QStyleOptionButton
    \value SO_ComboBox \l QStyleOptionComboBox
    \value SO_Complex \l QStyleOptionComplex
    \value SO_Default QStyleOption
    \value SO_DockWidget \l QStyleOptionDockWidget
    \value SO_FocusRect \l QStyleOptionFocusRect
    \value SO_Frame \l QStyleOptionFrame \l QStyleOptionFrameV2
    \value SO_GraphicsItem \l QStyleOptionGraphicsItem
    \value SO_GroupBox \l QStyleOptionGroupBox
    \value SO_Header \l QStyleOptionHeader
    \value SO_MenuItem \l QStyleOptionMenuItem
    \value SO_ProgressBar \l QStyleOptionProgressBar \l QStyleOptionProgressBarV2
    \value SO_RubberBand \l QStyleOptionRubberBand
    \value SO_SizeGrip \l QStyleOptionSizeGrip
    \value SO_Slider \l QStyleOptionSlider
    \value SO_SpinBox \l QStyleOptionSpinBox
    \value SO_Tab \l QStyleOptionTab
    \value SO_TabBarBase \l QStyleOptionTabBarBase
    \value SO_TabWidgetFrame \l QStyleOptionTabWidgetFrame
    \value SO_TitleBar \l QStyleOptionTitleBar
    \value SO_ToolBar \l QStyleOptionToolBar
    \value SO_ToolBox \l QStyleOptionToolBox
    \value SO_ToolButton \l QStyleOptionToolButton
    \value SO_ViewItem \l QStyleOptionViewItem (used in Interviews)

    The following values are used for custom controls:

    \value SO_CustomBase Reserved for custom QStyleOptions;
                         all custom controls values must be above this value
    \value SO_ComplexCustomBase Reserved for custom QStyleOptions;
                         all custom complex controls values must be above this value

    Some style options are defined for various Qt3Support controls:

    \value SO_Q3DockWindow \l QStyleOptionQ3DockWindow
    \value SO_Q3ListView \l QStyleOptionQ3ListView
    \value SO_Q3ListViewItem \l QStyleOptionQ3ListViewItem

    \sa type
*/

/*!
    Constructs a QStyleOption with the specified \a version and \a
    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 \l state member variable is initialized to
    QStyle::State_None.

    \sa version, type
*/

QStyleOption::QStyleOption(int version, int type)
    : version(version), type(type), state(QStyle::State_None),
      direction(QApplication::layoutDirection()), fontMetrics(QFont())
{
}


/*!
    Destroys this style option object.
*/
QStyleOption::~QStyleOption()
{
}

/*!
    \fn void QStyleOption::initFrom(const QWidget *widget)
    \since 4.1

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

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

    \sa QWidget::layoutDirection(), QWidget::rect(),
        QWidget::palette(), QWidget::fontMetrics()
*/

/*!
    \obsolete

    Use initFrom(\a widget) instead.
*/
void QStyleOption::init(const QWidget *widget)
{
    QWidget *window = widget->window();
    state = QStyle::State_None;
    if (widget->isEnabled())
        state |= QStyle::State_Enabled;
    if (widget->hasFocus())
        state |= QStyle::State_HasFocus;
    if (window->testAttribute(Qt::WA_KeyboardFocusChange))
        state |= QStyle::State_KeyboardFocusChange;
    if (widget->underMouse())
        state |= QStyle::State_MouseOver;
    if (window->isActiveWindow())
        state |= QStyle::State_Active;
    if (widget->isWindow())
        state |= QStyle::State_Window;
#ifdef Q_WS_MAC
    extern bool qt_mac_can_clickThrough(const QWidget *w); //qwidget_mac.cpp
    if (!(state & QStyle::State_Active) && !qt_mac_can_clickThrough(widget))
        state &= ~QStyle::State_Enabled;

    switch (QMacStyle::widgetSizePolicy(widget)) {
    case QMacStyle::SizeSmall:
        state |= QStyle::State_Small;
        break;
    case QMacStyle::SizeMini:
        state |= QStyle::State_Mini;
        break;
    default:
        ;
    }
#endif
#ifdef QT_KEYPAD_NAVIGATION
    if (widget->hasEditFocus())
        state |= QStyle::State_HasEditFocus;
#endif

    direction = widget->layoutDirection();
    rect = widget->rect();
    palette = widget->palette();
    fontMetrics = widget->fontMetrics();
}

/*!
   Constructs a copy of \a other.
*/
QStyleOption::QStyleOption(const QStyleOption &other)
    : version(Version), type(Type), state(other.state),
      direction(other.direction), rect(other.rect), fontMetrics(other.fontMetrics),
      palette(other.palette)
{
}

/*!
    Assign \a other to this QStyleOption.
*/
QStyleOption &QStyleOption::operator=(const QStyleOption &other)
{
    state = other.state;
    direction = other.direction;
    rect = other.rect;
    fontMetrics = other.fontMetrics;
    palette = other.palette;
    return *this;
}

/*!
    \enum QStyleOption::StyleOptionType

    This enum is used to hold information about the type of the style option, and
    is defined for each QStyleOption subclass.

    \value Type The type of style option provided (\l{SO_Default} for
           this class).

    The type is used internally by QStyleOption, its subclasses, and
    qstyleoption_cast() to determine the type of style option. In
    general you do not need to worry about this unless you want to
    create your own QStyleOption subclass and your own styles.

    \sa StyleOptionVersion
*/

/*!
    \enum QStyleOption::StyleOptionVersion

    This enum is used to hold information about the version of the style option, and
    is defined for each QStyleOption subclass.

    \value Version 1

    The version is used by QStyleOption subclasses to implement
    extensions without breaking compatibility. If you use
    qstyleoption_cast(), you normally don't need to check it.

    \sa StyleOptionType
*/

/*!
    \variable QStyleOption::palette
    \brief the palette that should be used when painting the control

    By default, the application's default palette is used.

    \sa initFrom()
*/

/*!
    \variable QStyleOption::direction
    \brief the text layout direction that should be used when drawing text in the control

    By default, the layout direction is Qt::LeftToRight.

    \sa initFrom()
*/

/*!
    \variable QStyleOption::fontMetrics
    \brief the font metrics that should be used when drawing text in the control

    By default, the application's default font is used.

    \sa initFrom()
*/

/*!
    \variable QStyleOption::rect
    \brief the area that should be used for various calculations and painting

    This can have different meanings for different types of elements.
    For example, for a \l QStyle::CE_PushButton element it would be
    the rectangle for the entire button, while for a \l
    QStyle::CE_PushButtonLabel element it would be just the area for
    the push button label.

    The default value is a null rectangle, i.e. a rectangle with both
    the width and the height set to 0.

    \sa initFrom()
*/

/*!
    \variable QStyleOption::state
    \brief the style flags that are used when drawing the control

    The default value is QStyle::State_None.

    \sa initFrom(), QStyle::drawPrimitive(), QStyle::drawControl(),
    QStyle::drawComplexControl(), QStyle::State
*/

/*!
    \variable QStyleOption::type
    \brief the option type of the style option

    The default value is SO_Default.

    \sa OptionType
*/

/*!
    \variable QStyleOption::version
    \brief the version of the style option

    This value can be used by subclasses to implement extensions
    without breaking compatibility. If you use the qstyleoption_cast()
    function, you normally don't need to check it.

    The default value is 1.
*/

/*!
    \class QStyleOptionFocusRect
    \brief The QStyleOptionFocusRect class is used to describe the
    parameters for drawing a focus rectangle with QStyle.

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

    For an example demonstrating how style options can be used, see
    the \l {widgets/styles}{Styles} example.

    \sa QStyleOption
*/

/*!
    Constructs a QStyleOptionFocusRect, initializing the members
    variables to their default values.
*/

QStyleOptionFocusRect::QStyleOptionFocusRect()
    : QStyleOption(Version, SO_FocusRect)
{
    state |= QStyle::State_KeyboardFocusChange; // assume we had one, will be corrected in initFrom()
}

/*!
    \internal
*/
QStyleOptionFocusRect::QStyleOptionFocusRect(int version)
    : QStyleOption(version, SO_FocusRect)
{
    state |= QStyle::State_KeyboardFocusChange;  // assume we had one, will be corrected in initFrom()
}

/*!
    \enum QStyleOptionFocusRect::StyleOptionType

    This enum is used to hold information about the type of the style option, and
    is defined for each QStyleOption subclass.

    \value Type The type of style option provided (\l{SO_FocusRect} for this class).

    The type is used internally by QStyleOption, its subclasses, and
    qstyleoption_cast() to determine the type of style option. In
    general you do not need to worry about this unless you want to
    create your own QStyleOption subclass and your own styles.

    \sa StyleOptionVersion
*/

/*!
    \enum QStyleOptionFocusRect::StyleOptionVersion

    This enum is used to hold information about the version of the style option, and
    is defined for each QStyleOption subclass.

    \value Version 1

    The version is used by QStyleOption subclasses to implement
    extensions without breaking compatibility. If you use
    qstyleoption_cast(), you normally don't need to check it.

    \sa StyleOptionType
*/

/*!