qstyle.cpp

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#include "qstyle.h"
#include "qapplication.h"
#include "qpainter.h"
#include "qwidget.h"
#include "qbitmap.h"
#include "qpixmapcache.h"
#include "qstyleoption.h"
#include "private/qstyle_p.h"
#ifndef QT_NO_DEBUG
#include "qdebug.h"
#endif

#ifdef Q_WS_X11
#include <qx11info_x11.h>
#endif

#include <limits.h>

QT_BEGIN_NAMESPACE

static const int MaxBits = 8 * sizeof(QSizePolicy::ControlType);

static int unpackControlTypes(QSizePolicy::ControlTypes controls, QSizePolicy::ControlType *array)
{
    if (!controls)
        return 0;

    // optimization: exactly one bit is set
    if ((controls & (controls - 1)) == 0) {
        array[0] = QSizePolicy::ControlType(uint(controls));
        return 1;
    }

    int count = 0;
    for (int i = 0; i < MaxBits; ++i) {
        if (uint bit = (controls & (0x1 << i)))
            array[count++] = QSizePolicy::ControlType(bit);
    }
    return count;
}

QStyle::QStyle()
    : QObject(*new QStylePrivate)
{
    Q_D(QStyle);
    d->proxyStyle = this;
}

QStyle::QStyle(QStylePrivate &dd)
    : QObject(dd)
{
  Q_D(QStyle);
  d->proxyStyle = this;
}

QStyle::~QStyle()
{
}

void QStyle::polish(QWidget * /* widget */)
{
}

void QStyle::unpolish(QWidget * /* widget */)
{
}

void QStyle::polish(QApplication * /* app */)
{
}

void QStyle::unpolish(QApplication * /* app */)
{
}

void QStyle::polish(QPalette & /* pal */)
{
}

QRect QStyle::itemTextRect(const QFontMetrics &metrics, const QRect &rect, int alignment, bool enabled,
                       const QString &text) const
{
    QRect result;
    int x, y, w, h;
    rect.getRect(&x, &y, &w, &h);
    if (!text.isEmpty()) {
        result = metrics.boundingRect(x, y, w, h, alignment, text);
        if (!enabled && proxy()->styleHint(SH_EtchDisabledText)) {
            result.setWidth(result.width()+1);
            result.setHeight(result.height()+1);
        }
    } else {
        result = QRect(x, y, w, h);
    }
    return result;
}

QRect QStyle::itemPixmapRect(const QRect &rect, int alignment, const QPixmap &pixmap) const
{
    QRect result;
    int x, y, w, h;
    rect.getRect(&x, &y, &w, &h);
    if ((alignment & Qt::AlignVCenter) == Qt::AlignVCenter)
        y += h/2 - pixmap.height()/2;
    else if ((alignment & Qt::AlignBottom) == Qt::AlignBottom)
        y += h - pixmap.height();
    if ((alignment & Qt::AlignRight) == Qt::AlignRight)
        x += w - pixmap.width();
    else if ((alignment & Qt::AlignHCenter) == Qt::AlignHCenter)
        x += w/2 - pixmap.width()/2;
    else if ((alignment & Qt::AlignLeft) != Qt::AlignLeft && QApplication::isRightToLeft())
        x += w - pixmap.width();
    result = QRect(x, y, pixmap.width(), pixmap.height());
    return result;
}

void QStyle::drawItemText(QPainter *painter, const QRect &rect, int alignment, const QPalette &pal,
                          bool enabled, const QString& text, QPalette::ColorRole textRole) const
{
    if (text.isEmpty())
        return;
    QPen savedPen;
    if (textRole != QPalette::NoRole) {
        savedPen = painter->pen();
        painter->setPen(QPen(pal.brush(textRole), savedPen.widthF()));
    }
    if (!enabled) {
        if (proxy()->styleHint(SH_DitherDisabledText)) {
            QRect br;
            painter->drawText(rect, alignment, text, &br);
            painter->fillRect(br, QBrush(painter->background().color(), Qt::Dense5Pattern));
            return;
        } else if (proxy()->styleHint(SH_EtchDisabledText)) {
            QPen pen = painter->pen();
            painter->setPen(pal.light().color());
            painter->drawText(rect.adjusted(1, 1, 1, 1), alignment, text);
            painter->setPen(pen);
        }
    }
    painter->drawText(rect, alignment, text);
    if (textRole != QPalette::NoRole)
        painter->setPen(savedPen);
}

void QStyle::drawItemPixmap(QPainter *painter, const QRect &rect, int alignment,
                            const QPixmap &pixmap) const
{
    QRect aligned = alignedRect(QApplication::layoutDirection(), QFlag(alignment), pixmap.size(), rect);
    QRect inter = aligned.intersected(rect);

    painter->drawPixmap(inter.x(), inter.y(), pixmap, inter.x() - aligned.x(), inter.y() - aligned.y(), inter.width(), inter.height());
}

QRect QStyle::visualRect(Qt::LayoutDirection direction, const QRect &boundingRect, const QRect &logicalRect)
{
    if (direction == Qt::LeftToRight)
        return logicalRect;
    QRect rect = logicalRect;
    rect.translate(2 * (boundingRect.right() - logicalRect.right()) +
                   logicalRect.width() - boundingRect.width(), 0);
    return rect;
}

QPoint QStyle::visualPos(Qt::LayoutDirection direction, const QRect &boundingRect, const QPoint &logicalPos)
{
    if (direction == Qt::LeftToRight)
        return logicalPos;
    return QPoint(boundingRect.right() - logicalPos.x(), logicalPos.y());
}

QRect QStyle::alignedRect(Qt::LayoutDirection direction, Qt::Alignment alignment, const QSize &size, const QRect &rectangle)
{
    alignment = visualAlignment(direction, alignment);
    int x = rectangle.x();
    int y = rectangle.y();
    int w = size.width();
    int h = size.height();
    if ((alignment & Qt::AlignVCenter) == Qt::AlignVCenter)
        y += rectangle.size().height()/2 - h/2;
    else if ((alignment & Qt::AlignBottom) == Qt::AlignBottom)
        y += rectangle.size().height() - h;
    if ((alignment & Qt::AlignRight) == Qt::AlignRight)
        x += rectangle.size().width() - w;
    else if ((alignment & Qt::AlignHCenter) == Qt::AlignHCenter)
        x += rectangle.size().width()/2 - w/2;
    return QRect(x, y, w, h);
}

Qt::Alignment QStyle::visualAlignment(Qt::LayoutDirection direction, Qt::Alignment alignment)
{
    if (!(alignment & Qt::AlignHorizontal_Mask))
        alignment |= Qt::AlignLeft;
    if ((alignment & Qt::AlignAbsolute) == 0 && (alignment & (Qt::AlignLeft | Qt::AlignRight))) {
        if (direction == Qt::RightToLeft)
            alignment ^= (Qt::AlignLeft | Qt::AlignRight);
        alignment |= Qt::AlignAbsolute;
    }
    return alignment;
}

int QStyle::sliderPositionFromValue(int min, int max, int logicalValue, int span, bool upsideDown)
{
    if (span <= 0 || logicalValue < min || max <= min)
        return 0;
    if (logicalValue > max)
        return upsideDown ? span : min;

    uint range = max - min;
    uint p = upsideDown ? max - logicalValue : logicalValue - min;

    if (range > (uint)INT_MAX/4096) {
        double dpos = (double(p))/(double(range)/span);
        return int(dpos);
    } else if (range > (uint)span) {
        return (2 * p * span + range) / (2*range);
    } else {
        uint div = span / range;
        uint mod = span % range;
        return p * div + (2 * p * mod + range) / (2 * range);
    }
    // equiv. to (p * span) / range + 0.5
    // no overflow because of this implicit assumption:
    // span <= 4096
}

int QStyle::sliderValueFromPosition(int min, int max, int pos, int span, bool upsideDown)
{
    if (span <= 0 || pos <= 0)
        return upsideDown ? max : min;
    if (pos >= span)
        return upsideDown ? min : max;

    uint range = max - min;

    if ((uint)span > range) {
        int tmp = (2 * pos * range + span) / (2 * span);
        return upsideDown ? max - tmp : tmp + min;
    } else {
        uint div = range / span;
        uint mod = range % span;
        int tmp = pos * div + (2 * pos * mod + span) / (2 * span);
        return upsideDown ? max - tmp : tmp + min;
    }
    // equiv. to min + (pos*range)/span + 0.5
    // no overflow because of this implicit assumption:
    // pos <= span < sqrt(INT_MAX+0.0625)+0.25 ~ sqrt(INT_MAX)
}

/*### \fn void QStyle::drawItem(QPainter *p, const QRect &r,
                              int flags, const QColorGroup &colorgroup, bool enabled,
                              const QString &text, int len = -1,
                              const QColor *penColor = 0) const

    Use one of the drawItem() overloads that takes a QPalette instead
    of a QColorGroup.
*/

/*### \fn void QStyle::drawItem(QPainter *p, const QRect &r,
                              int flags, const QColorGroup colorgroup, bool enabled,
                              const QPixmap &pixmap,
                              const QColor *penColor = 0) const

    Use one of the drawItem() overloads that takes a QPalette instead
    of a QColorGroup.
*/

/*### \fn void QStyle::drawItem(QPainter *p, const QRect &r,
                          int flags, const QColorGroup colorgroup, bool enabled,
                          const QPixmap *pixmap,
                          const QString &text, int len = -1,
                          const QColor *penColor = 0) const

    Use one of the drawItem() overloads that takes a QPalette instead
    of a QColorGroup.
*/

QPalette QStyle::standardPalette() const
{
#ifdef Q_WS_X11
    QColor background;
    if (QX11Info::appDepth() > 8)
        background = QColor(0xd4, 0xd0, 0xc8); // win 2000 grey
    else
        background = QColor(192, 192, 192);
#else
    QColor background(0xd4, 0xd0, 0xc8); // win 2000 grey
#endif
    QColor light(background.lighter());
    QColor dark(background.darker());
    QColor mid(Qt::gray);
    QPalette palette(Qt::black, background, light, dark, mid, Qt::black, Qt::white);
    palette.setBrush(QPalette::Disabled, QPalette::WindowText, dark);
    palette.setBrush(QPalette::Disabled, QPalette::Text, dark);
    palette.setBrush(QPalette::Disabled, QPalette::ButtonText, dark);
    palette.setBrush(QPalette::Disabled, QPalette::Base, background);
    return palette;
}

QIcon QStyle::standardIcon(StandardPixmap standardIcon, const QStyleOption *option,
                           const QWidget *widget) const
{
    QIcon result;
    // ### Qt 4.1: invokeMethod should accept const functions, to avoid this dirty cast
    QMetaObject::invokeMethod(const_cast<QStyle*>(this),
                              "standardIconImplementation", Qt::DirectConnection,
                              Q_RETURN_ARG(QIcon, result),
                              Q_ARG(StandardPixmap, standardIcon),
                              Q_ARG(const QStyleOption*, option),
                              Q_ARG(const QWidget*, widget));
    return result;
}

QIcon QStyle::standardIconImplementation(StandardPixmap standardIcon, const QStyleOption *option,
                                         const QWidget *widget) const
{
    return QIcon(standardPixmap(standardIcon, option, widget));
}

int QStyle::layoutSpacing(QSizePolicy::ControlType control1, QSizePolicy::ControlType control2,
                          Qt::Orientation orientation, const QStyleOption *option,
                          const QWidget *widget) const
{
    Q_D(const QStyle);
    if (d->layoutSpacingIndex == -1) {
        d->layoutSpacingIndex = metaObject()->indexOfMethod(
            "layoutSpacingImplementation(QSizePolicy::ControlType,QSizePolicy::ControlType,"
            "Qt::Orientation,const QStyleOption*,const QWidget*)"
            );
    }
    if (d->layoutSpacingIndex < 0)
        return -1;
    int result = -1;
    void *param[] = {&result, &control1, &control2, &orientation, &option, &widget};

    const_cast<QStyle *>(this)->qt_metacall(QMetaObject::InvokeMetaMethod,
                                            d->layoutSpacingIndex, param);
    return result;
}

int QStyle::combinedLayoutSpacing(QSizePolicy::ControlTypes controls1,
                                  QSizePolicy::ControlTypes controls2, Qt::Orientation orientation,
                                  QStyleOption *option, QWidget *widget) const
{
    QSizePolicy::ControlType array1[MaxBits];
    QSizePolicy::ControlType array2[MaxBits];
    int count1 = unpackControlTypes(controls1, array1);
    int count2 = unpackControlTypes(controls2, array2);
    int result = -1;

    for (int i = 0; i < count1; ++i) {
        for (int j = 0; j < count2; ++j) {
            int spacing = layoutSpacing(array1[i], array2[j], orientation, option, widget);
            result = qMax(spacing, result);
        }
    }
    return result;
}

int QStyle::layoutSpacingImplementation(QSizePolicy::ControlType /* control1 */,
                                        QSizePolicy::ControlType /* control2 */,
                                        Qt::Orientation /*orientation*/,
                                        const QStyleOption * /* option */,
                                        const QWidget * /* widget */) const
{
    return -1;
}

QT_BEGIN_INCLUDE_NAMESPACE
#include <QDebug>
QT_END_INCLUDE_NAMESPACE

#if !defined(QT_NO_DEBUG_STREAM)
QDebug operator<<(QDebug debug, QStyle::State state)
{
#if !defined(QT_NO_DEBUG)
    debug << "QStyle::State(";

    QStringList states;
    if (state & QStyle::State_Active) states << QLatin1String("Active");
    if (state & QStyle::State_AutoRaise) states << QLatin1String("AutoRaise");
    if (state & QStyle::State_Bottom) states << QLatin1String("Bottom");
    if (state & QStyle::State_Children) states << QLatin1String("Children");
    if (state & QStyle::State_DownArrow) states << QLatin1String("DownArrow");
    if (state & QStyle::State_Editing) states << QLatin1String("Editing");
    if (state & QStyle::State_Enabled) states << QLatin1String("Enabled");
    if (state & QStyle::State_FocusAtBorder) states << QLatin1String("FocusAtBorder");
    if (state & QStyle::State_HasFocus) states << QLatin1String("HasFocus");
    if (state & QStyle::State_Horizontal) states << QLatin1String("Horizontal");
    if (state & QStyle::State_Item) states << QLatin1String("Item");
    if (state & QStyle::State_KeyboardFocusChange) states << QLatin1String("KeyboardFocusChange");
    if (state & QStyle::State_MouseOver) states << QLatin1String("MouseOver");
    if (state & QStyle::State_NoChange) states << QLatin1String("NoChange");
    if (state & QStyle::State_Off) states << QLatin1String("Off");
    if (state & QStyle::State_On) states << QLatin1String("On");
    if (state & QStyle::State_Open) states << QLatin1String("Open");
    if (state & QStyle::State_Raised) states << QLatin1String("Raised");
    if (state & QStyle::State_ReadOnly) states << QLatin1String("ReadOnly");
    if (state & QStyle::State_Selected) states << QLatin1String("Selected");
    if (state & QStyle::State_Sibling) states << QLatin1String("Sibling");
    if (state & QStyle::State_Sunken) states << QLatin1String("Sunken");
    if (state & QStyle::State_Top) states << QLatin1String("Top");
    if (state & QStyle::State_UpArrow) states << QLatin1String("UpArrow");

    qSort(states);
    debug << states.join(QLatin1String(" | "));
    debug << ')';
#else
    Q_UNUSED(state);
#endif
    return debug;
}
#endif

const QStyle * QStyle::proxy() const
{
    Q_D(const QStyle);
    return d->proxyStyle;
}

/* \internal

    This function sets the base style that style calls will be
    redirected to. Note that ownership is not transferred.
*/
void QStyle::setProxy(QStyle *style)
{
    Q_D(QStyle);
    d->proxyStyle = style;
}

QT_END_NAMESPACE