source: trunk/src/gui/kernel/qpalette.cpp@ 856

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#include "qpalette.h"
#include "qapplication.h"
#include "qdatastream.h"
#include "qvariant.h"

QT_BEGIN_NAMESPACE

static int qt_palette_count = 1;

class QPalettePrivate {
public:
    QPalettePrivate() : ref(1), ser_no(qt_palette_count++), detach_no(0) { }
    QAtomicInt ref;
    QBrush br[QPalette::NColorGroups][QPalette::NColorRoles];
    int ser_no;
    int detach_no;
};

static QColor qt_mix_colors(QColor a, QColor b)
{
    return QColor((a.red() + b.red()) / 2, (a.green() + b.green()) / 2,
                  (a.blue() + b.blue()) / 2, (a.alpha() + b.alpha()) / 2);
}

#ifdef QT3_SUPPORT

#ifndef QT_NO_DATASTREAM
QDataStream &qt_stream_out_qcolorgroup(QDataStream &s, const QColorGroup &g)
{
    if(s.version() == 1) {
        // Qt 1.x
        s << g.color(QPalette::Foreground) << g.color(QPalette::Background)
          << g.color(QPalette::Light) << g.color(QPalette::Dark)
          << g.color(QPalette::Mid) << g.color(QPalette::Text) << g.color(QPalette::Base);
    } else {
        int max = QPalette::NColorRoles;
        if (s.version() <= QDataStream::Qt_2_1)
            max = QPalette::HighlightedText + 1;
        else if (s.version() <= QDataStream::Qt_4_3)
            max = QPalette::AlternateBase + 1;
        for(int r = 0 ; r < max ; r++)
            s << g.brush((QPalette::ColorRole)r);
    }
    return s;
}

QDataStream &qt_stream_in_qcolorgroup(QDataStream &s, QColorGroup &g)
{
    if(s.version() == 1) {         // Qt 1.x
        QColor fg, bg, light, dark, mid, text, base;
        s >> fg >> bg >> light >> dark >> mid >> text >> base;
        QPalette p(bg);
        p.setColor(QPalette::Active, QPalette::Foreground, fg);
        p.setColor(QPalette::Active, QPalette::Light, light);
        p.setColor(QPalette::Active, QPalette::Dark, dark);
        p.setColor(QPalette::Active, QPalette::Mid, mid);
        p.setColor(QPalette::Active, QPalette::Text, text);
        p.setColor(QPalette::Active, QPalette::Base, base);
        g = p;
        g.setCurrentColorGroup(QPalette::Active);
    } else {
        int max = QPalette::NColorRoles;
        if (s.version() <= QDataStream::Qt_2_1)
            max = QPalette::HighlightedText + 1;
        else if (s.version() <= QDataStream::Qt_3_0)
            max = QPalette::LinkVisited + 1;
        else if (s.version() <= QDataStream::Qt_4_3)
            max = QPalette::AlternateBase + 1;
        QBrush tmp;
        for(int r = 0 ; r < max; r++) {
            s >> tmp;
            g.setBrush((QPalette::ColorRole)r, tmp);
        }
    }
    return s;
}

QDataStream &operator<<(QDataStream &s, const QColorGroup &g)
{
    return qt_stream_out_qcolorgroup(s, g);
}

QDataStream &operator>>(QDataStream &s, QColorGroup &g)
{
    return qt_stream_in_qcolorgroup(s, g);
}
#endif // QT_NO_DATASTREAM

/*!
    Constructs a palette with the specified \a active, \a disabled and
    \a inactive color groups.
*/
QPalette::QPalette(const QColorGroup &active, const QColorGroup &disabled,
                   const QColorGroup &inactive)
{
    Q_ASSERT(QPalette::NColorRoles == QPalette::ToolTipText + 1);
    init();
    setColorGroup(Active, active);
    setColorGroup(Disabled, disabled);
    setColorGroup(Inactive, inactive);
}

QColorGroup QPalette::createColorGroup(ColorGroup cr) const
{
    QColorGroup ret(*this);
    ret.setCurrentColorGroup(cr);
    return ret;
}

void QPalette::setColorGroup(ColorGroup cg, const QColorGroup &g)
{
    setColorGroup(cg, g.brush(WindowText), g.brush(Button), g.brush(Light),
                  g.brush(Dark), g.brush(Mid), g.brush(Text), g.brush(BrightText),
                  g.brush(Base), g.brush(AlternateBase), g.brush(Window),
                  g.brush(Midlight), g.brush(ButtonText), g.brush(Shadow),
                  g.brush(Highlight), g.brush(HighlightedText), g.brush(Link),
                  g.brush(LinkVisited), g.brush(ToolTipBase), g.brush(ToolTipText));
}

#endif // QT3_SUPPORT

/*!
   \fn const QColor &QPalette::color(ColorRole role) const

   \overload

    Returns the color that has been set for the given color \a role in
    the current ColorGroup.

    \sa brush() ColorRole
 */

/*!
    \fn const QBrush &QPalette::brush(ColorRole role) const

    \overload

    Returns the brush that has been set for the given color \a role in
    the current ColorGroup.

    \sa color() setBrush() ColorRole
*/

/*!
    \fn void QPalette::setColor(ColorRole role, const QColor &color)

    \overload

    Sets the color used for the given color \a role, in all color
    groups, to the specified solid \a color.

    \sa brush() setColor() ColorRole
*/

/*!
    \fn void QPalette::setBrush(ColorRole role, const QBrush &brush)

    Sets the brush for the given color \a role to the specified \a
    brush for all groups in the palette.

    \sa brush() setColor() ColorRole
*/

/*!
    \fn const QBrush & QPalette::foreground() const
    \obsolete

    Use windowText() instead.
*/

/*!
    \fn const QBrush & QPalette::windowText() const

    Returns the window text (general foreground) brush of the
    current color group.

    \sa ColorRole brush()
*/

/*!
    \fn const QBrush & QPalette::button() const

    Returns the button brush of the current color group.

    \sa ColorRole brush()
*/

/*!
    \fn const QBrush & QPalette::light() const

    Returns the light brush of the current color group.

    \sa ColorRole brush()
*/

/*!
    \fn const QBrush& QPalette::midlight() const

    Returns the midlight brush of the current color group.

    \sa ColorRole brush()
*/

/*!
    \fn const QBrush & QPalette::dark() const

    Returns the dark brush of the current color group.

    \sa ColorRole brush()
*/

/*!
    \fn const QBrush & QPalette::mid() const

    Returns the mid brush of the current color group.

    \sa ColorRole brush()
*/

/*!
    \fn const QBrush & QPalette::text() const

    Returns the text foreground brush of the current color group.

    \sa ColorRole brush()
*/

/*!
    \fn const QBrush & QPalette::brightText() const

    Returns the bright text foreground brush of the current color group.

    \sa ColorRole brush()
*/

/*!
    \fn const QBrush & QPalette::buttonText() const

    Returns the button text foreground brush of the current color group.

    \sa ColorRole brush()
*/

/*!
    \fn const QBrush & QPalette::base() const

    Returns the base brush of the current color group.

    \sa ColorRole brush()
*/

/*!
    \fn const QBrush & QPalette::alternateBase() const

    Returns the alternate base brush of the current color group.

    \sa ColorRole brush()
*/

/*!
    \fn const QBrush & QPalette::toolTipBase() const
    \since 4.4

    Returns the tool tip base brush of the current color group. This brush is
    used by QToolTip and QWhatsThis.

    \note Tool tips use the Inactive color group of QPalette, because tool
    tips are not active windows.

    \sa ColorRole brush()
*/

/*!
    \fn const QBrush & QPalette::toolTipText() const
    \since 4.4

    Returns the tool tip text brush of the current color group. This brush is
    used by QToolTip and QWhatsThis.

    \note Tool tips use the Inactive color group of QPalette, because tool
    tips are not active windows.

    \sa ColorRole brush()
*/

/*!
    \fn const QBrush & QPalette::background() const
    \obsolete

    Use window() instead.
*/

/*!
    \fn const QBrush & QPalette::window() const

    Returns the window (general background) brush of the current
    color group.

    \sa ColorRole brush()
*/

/*!
    \fn const QBrush & QPalette::shadow() const

    Returns the shadow brush of the current color group.

    \sa ColorRole brush()
*/

/*!
    \fn const QBrush & QPalette::highlight() const

    Returns the highlight brush of the current color group.

    \sa ColorRole brush()
*/

/*!
    \fn const QBrush & QPalette::highlightedText() const

    Returns the highlighted text brush of the current color group.

    \sa ColorRole brush()
*/

/*!
    \fn const QBrush & QPalette::link() const

    Returns the unvisited link text brush of the current color group.

    \sa ColorRole brush()
*/

/*!
    \fn const QBrush & QPalette::linkVisited() const

    Returns the visited link text brush of the current color group.

    \sa ColorRole brush()
*/

/*!
    \fn ColorGroup QPalette::currentColorGroup() const

    Returns the palette's current color group.
*/

/*!
    \fn void QPalette::setCurrentColorGroup(ColorGroup cg)

    Set the palette's current color group to \a cg.
*/

/*!
    \class QPalette

    \brief The QPalette class contains color groups for each widget state.

    \ingroup appearance
    \ingroup shared
    \ingroup painting


    A palette consists of three color groups: \e Active, \e Disabled,
    and \e Inactive. All widgets in Qt contain a palette and
    use their palette to draw themselves. This makes the user
    interface easily configurable and easier to keep consistent.


    If you create a new widget we strongly recommend that you use the
    colors in the palette rather than hard-coding specific colors.

    The color groups:
    \list
    \i The Active group is used for the window that has keyboard focus.
    \i The Inactive group is used for other windows.
    \i The Disabled group is used for widgets (not windows) that are
    disabled for some reason.
    \endlist

    Both active and inactive windows can contain disabled widgets.
    (Disabled widgets are often called \e inaccessible or \e{grayed
    out}.)

    In most styles, Active and Inactive look the same.

    Colors and brushes can be set for particular roles in any of a palette's
    color groups with setColor() and setBrush().  A color group contains a
    group of colors used by widgets for drawing themselves. We recommend that
    widgets use color group roles from the palette such as "foreground" and
    "base" rather than literal colors like "red" or "turquoise". The color
    roles are enumerated and defined in the \l ColorRole documentation.

    We strongly recommend that you use the default palette of the
    current style (returned by QApplication::palette()) and
    modify that as necessary. This is done by Qt's widgets when they
    are drawn.

    To modify a color group you call the functions
    setColor() and setBrush(), depending on whether you want a pure
    color or a pixmap pattern.

    There are also corresponding color() and brush() getters, and a
    commonly used convenience function to get the ColorRole for the current ColorGroup:
    window(), windowText(), base(), etc.


    You can copy a palette using the copy constructor and test to see
    if two palettes are \e identical using isCopyOf().

    QPalette is optimized by the use of \l{implicit sharing},
    so it is very efficient to pass QPalette objects as arguments.

    \warning Some styles do not use the palette for all drawing, for
    instance, if they make use of native theme engines. This is the
    case for both the Windows XP, Windows Vista, and the Mac OS X
    styles.

    \sa QApplication::setPalette(), QWidget::setPalette(), QColor
*/

/*!
    \enum QPalette::ColorGroup

    \value Disabled
    \value Active
    \value Inactive
    \value Normal synonym for Active

    \omitvalue All
    \omitvalue NColorGroups
    \omitvalue Current
*/

/*!
    \enum QPalette::ColorRole

    \img palette.png Color Roles

    The ColorRole enum defines the different symbolic color roles used
    in current GUIs.

    The central roles are:

    \value Window  A general background color.

    \value Background  This value is obsolete. Use Window instead.

    \value WindowText  A general foreground color.

    \value Foreground  This value is obsolete. Use WindowText instead.

    \value Base  Used mostly as the background color for text entry widgets,
                 but can also be used for other painting - such as the
                 background of combobox drop down lists and toolbar handles.
                 It is usually white or another light color.

    \value AlternateBase  Used as the alternate background color in views with
                          alternating row colors (see
                          QAbstractItemView::setAlternatingRowColors()).

    \value ToolTipBase Used as the background color for QToolTip and
                          QWhatsThis. Tool tips use the Inactive color group
                          of QPalette, because tool tips are not active
                          windows.

    \value ToolTipText Used as the foreground color for QToolTip and
                          QWhatsThis. Tool tips use the Inactive color group
                          of QPalette, because tool tips are not active
                          windows.

    \value Text  The foreground color used with \c Base. This is usually
                 the same as the \c WindowText, in which case it must provide
                 good contrast with \c Window and \c Base.

    \value Button The general button background color. This background can be different from
                  \c Window as some styles require a different background color for buttons.

    \value ButtonText  A foreground color used with the \c Button color.

    \value BrightText  A text color that is very different from
                       \c WindowText, and contrasts well with e.g. \c
                       Dark. Typically used for text that needs to be
                       drawn where \c Text or \c WindowText would give
                       poor contrast, such as on pressed push buttons.
                       Note that text colors can be used for things
                       other than just words; text colors are \e
                       usually used for text, but it's quite common to
                       use the text color roles for lines, icons, etc.


    There are some color roles used mostly for 3D bevel and shadow effects.
    All of these are normally derived from \c Window, and used in ways that
    depend on that relationship. For example, buttons depend on it to make the
    bevels look attractive, and Motif scroll bars depend on \c Mid to be
    slightly different from \c Window.

    \value Light  Lighter than \c Button color.

    \value Midlight  Between \c Button and \c Light.

    \value Dark  Darker than \c Button.

    \value Mid  Between \c Button and \c Dark.

    \value Shadow  A very dark color. By default, the shadow color is
                   Qt::black.


    Selected (marked) items have two roles:

    \value Highlight   A color to indicate a selected item or the current
                       item. By default, the highlight color is
                       Qt::darkBlue.

    \value HighlightedText  A text color that contrasts with \c Highlight.
                            By default, the highlighted text color is Qt::white.

    There are two color roles related to hyperlinks:

    \value Link  A text color used for unvisited hyperlinks.
                 By default, the link color is Qt::blue.

    \value LinkVisited  A text color used for already visited hyperlinks.
                        By default, the linkvisited color is Qt::magenta.

    Note that we do not use the \c Link and \c LinkVisited roles when
    rendering rich text in Qt, and that we recommend that you use CSS
    and the QTextDocument::setDefaultStyleSheet() function to alter
    the appearance of links. For example:

    \snippet doc/src/snippets/textdocument-css/main.cpp 0

    \value NoRole No role; this special role is often used to indicate that a
    role has not been assigned.

    \omitvalue NColorRoles
*/

/*!
    Constructs a palette object that uses the application's default palette.

    \sa QApplication::setPalette(), QApplication::palette()
*/
QPalette::QPalette()
    : d(QApplication::palette().d),
      current_group(Active),
      resolve_mask(0)
{
    d->ref.ref();
}

static void qt_palette_from_color(QPalette &pal, const QColor & button)
{
    QColor bg = button,
           btn = button,
           fg, base;
    int h, s, v;
    bg.getHsv(&h, &s, &v);
    if(v > 128) {
        fg   = Qt::black;
        base = Qt::white;
    } else {
        fg   = Qt::white;
        base = Qt::black;
    }
    //inactive and active are the same..
    pal.setColorGroup(QPalette::Active, QBrush(fg), QBrush(btn), QBrush(btn.lighter(150)),
                      QBrush(btn.darker()), QBrush(btn.darker(150)), QBrush(fg), QBrush(Qt::white),
                      QBrush(base), QBrush(bg));
    pal.setColorGroup(QPalette::Inactive, QBrush(fg), QBrush(btn), QBrush(btn.lighter(150)),
                      QBrush(btn.darker()), QBrush(btn.darker(150)), QBrush(fg), QBrush(Qt::white),
                      QBrush(base), QBrush(bg));
    pal.setColorGroup(QPalette::Disabled, QBrush(btn.darker()), QBrush(btn), QBrush(btn.lighter(150)),
                      QBrush(btn.darker()), QBrush(btn.darker(150)), QBrush(btn.darker()),
                      QBrush(Qt::white), QBrush(bg), QBrush(bg));
}


/*!
  Constructs a palette from the \a button color. The other colors are
  automatically calculated, based on this color. \c Window will be
  the button color as well.
*/
QPalette::QPalette(const QColor &button)
{
    init();
    qt_palette_from_color(*this, button);
}

/*!
  Constructs a palette from the \a button color. The other colors are
  automatically calculated, based on this color. \c Window will be
  the button color as well.
*/
QPalette::QPalette(Qt::GlobalColor button)
{
    init();
    qt_palette_from_color(*this, button);
}

/*!
    Constructs a palette. You can pass either brushes, pixmaps or
    plain colors for \a windowText, \a button, \a light, \a dark, \a
    mid, \a text, \a bright_text, \a base and \a window.

    \sa QBrush
*/
QPalette::QPalette(const QBrush &windowText, const QBrush &button,
                   const QBrush &light, const QBrush &dark,
                   const QBrush &mid, const QBrush &text,
                   const QBrush &bright_text, const QBrush &base,
                   const QBrush &window)
{
    init();
    setColorGroup(All, windowText, button, light, dark, mid, text, bright_text,
                  base, window);
}


/*!\obsolete

  Constructs a palette with the specified \a windowText, \a
  window, \a light, \a dark, \a mid, \a text, and \a base colors.
  The button color will be set to the window color.
*/
QPalette::QPalette(const QColor &windowText, const QColor &window,
                   const QColor &light, const QColor &dark, const QColor &mid,
                   const QColor &text, const QColor &base)
{
    init();
    setColorGroup(All, QBrush(windowText), QBrush(window), QBrush(light),
                  QBrush(dark), QBrush(mid), QBrush(text), QBrush(light),
                  QBrush(base), QBrush(window));
}

/*!
    Constructs a palette from a \a button color and a \a window.
    The other colors are automatically calculated, based on these
    colors.
*/
QPalette::QPalette(const QColor &button, const QColor &window)
{
    init();
    QColor bg = window, btn = button, fg, base, disfg;
    int h, s, v;
    bg.getHsv(&h, &s, &v);
    if(v > 128) {
        fg   = Qt::black;
        base = Qt::white;
        disfg = Qt::darkGray;
    } else {
        fg   = Qt::white;
        base = Qt::black;
        disfg = Qt::darkGray;
    }
    //inactive and active are identical
    setColorGroup(Inactive, QBrush(fg), QBrush(btn), QBrush(btn.lighter(150)), QBrush(btn.darker()),
                  QBrush(btn.darker(150)), QBrush(fg), QBrush(Qt::white), QBrush(base),
                  QBrush(bg));
    setColorGroup(Active, QBrush(fg), QBrush(btn), QBrush(btn.lighter(150)), QBrush(btn.darker()),
                  QBrush(btn.darker(150)), QBrush(fg), QBrush(Qt::white), QBrush(base),
                  QBrush(bg));
    setColorGroup(Disabled, QBrush(disfg), QBrush(btn), QBrush(btn.lighter(150)),
                  QBrush(btn.darker()), QBrush(btn.darker(150)), QBrush(disfg),
                  QBrush(Qt::white), QBrush(base), QBrush(bg));
}

/*!
    Constructs a copy of \a p.

    This constructor is fast thanks to \l{implicit sharing}.
*/
QPalette::QPalette(const QPalette &p)
{
    d = p.d;
    d->ref.ref();
    resolve_mask = p.resolve_mask;
    current_group = p.current_group;
}

/*!
    Destroys the palette.
*/
QPalette::~QPalette()
{
    if(!d->ref.deref())
        delete d;
}

/*!\internal*/
void QPalette::init() {
    d = new QPalettePrivate;
    resolve_mask = 0;
    current_group = Active; //as a default..
}

/*!
    Assigns \a p to this palette and returns a reference to this
    palette.

    This operation is fast thanks to \l{implicit sharing}.
*/
QPalette &QPalette::operator=(const QPalette &p)
{
    p.d->ref.ref();
    resolve_mask = p.resolve_mask;
    current_group = p.current_group;
    if(!d->ref.deref())
        delete d;
    d = p.d;
    return *this;
}

/*!
   Returns the palette as a QVariant
*/
QPalette::operator QVariant() const
{
    return QVariant(QVariant::Palette, this);
}

/*!
    \fn const QColor &QPalette::color(ColorGroup group, ColorRole role) const

    Returns the color in the specified color \a group, used for the
    given color \a role.

    \sa brush() setColor() ColorRole
*/

/*!
    \fn const QBrush &QPalette::brush(ColorGroup group, ColorRole role) const

    Returns the brush in the specified color \a group, used for the
    given color \a role.

    \sa color() setBrush() ColorRole
*/
const QBrush &QPalette::brush(ColorGroup gr, ColorRole cr) const
{
    Q_ASSERT(cr < NColorRoles);
    if(gr >= (int)NColorGroups) {
        if(gr == Current) {
            gr = (ColorGroup)current_group;
        } else {
            qWarning("QPalette::brush: Unknown ColorGroup: %d", (int)gr);
            gr = Active;
        }
    }
    return d->br[gr][cr];
}

/*!
    \fn void QPalette::setColor(ColorGroup group, ColorRole role, const QColor &color)

    Sets the color in the specified color \a group, used for the given
    color \a role, to the specified solid \a color.

    \sa setBrush() color() ColorRole
*/

/*!
    \fn void QPalette::setBrush(ColorGroup group, ColorRole role, const QBrush &brush)
    \overload

    Sets the brush in the specified color \a group, used for the given
    color \a role, to \a brush.

    \sa brush() setColor() ColorRole
*/
void QPalette::setBrush(ColorGroup cg, ColorRole cr, const QBrush &b)
{
    Q_ASSERT(cr < NColorRoles);
    detach();
    if(cg >= (int)NColorGroups) {
        if(cg == All) {
            for(int i = 0; i < (int)NColorGroups; i++)
                d->br[i][cr] = b;
            resolve_mask |= (1<<cr);
            return;
        } else if(cg == Current) {
            cg = (ColorGroup)current_group;
        } else {
            qWarning("QPalette::setBrush: Unknown ColorGroup: %d", (int)cg);
            cg = Active;
        }
    }
    d->br[cg][cr] = b;
    resolve_mask |= (1<<cr);
}

/*!
    \since 4.2