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#include "qgroupbox.h"

#ifndef QT_NO_GROUPBOX

#include "qapplication.h"

#include "qbitmap.h"

#include "qdrawutil.h"

#include "qevent.h"

#include "qlayout.h"

#include "qradiobutton.h"

#include "qstyle.h"

#include "qstyleoption.h"

#include "qstylepainter.h"

#ifndef QT_NO_ACCESSIBILITY

#include "qaccessible.h"

#endif

#include <private/qwidget_p.h>

#include "qdebug.h"

QT_BEGIN_NAMESPACE

class QGroupBoxPrivate : public QWidgetPrivate

{

    Q_DECLARE_PUBLIC(QGroupBox)

public:

    void skip();

    void init();

    void calculateFrame();

    QString title;

    int align;

#ifndef QT_NO_SHORTCUT

    int shortcutId;

#endif

    void _q_fixFocus(Qt::FocusReason reason);

    void _q_setChildrenEnabled(bool b);

    void click();

    bool flat;

    bool checkable;

    bool checked;

    bool hover;

    bool overCheckBox;

    QStyle::SubControl pressedControl;

};

/*!

    Initialize \a option with the values from this QGroupBox. This method

    is useful for subclasses when they need a QStyleOptionGroupBox, but don't want

    to fill in all the information themselves.

    \sa QStyleOption::initFrom()

*/

void QGroupBox::initStyleOption(QStyleOptionGroupBox *option) const

{

    if (!option)

        return;

    Q_D(const QGroupBox);

    option->initFrom(this);

    option->text = d->title;

    option->lineWidth = 1;

    option->midLineWidth = 0;

    option->textAlignment = Qt::Alignment(d->align);

    option->activeSubControls |= d->pressedControl;

    option->subControls = QStyle::SC_GroupBoxFrame;

    if (d->hover)

        option->state |= QStyle::State_MouseOver;

    else

        option->state &= ~QStyle::State_MouseOver;

    if (d->flat)

        option->features |= QStyleOptionFrameV2::Flat;

    if (d->checkable) {

        option->subControls |= QStyle::SC_GroupBoxCheckBox;

        option->state |= (d->checked ? QStyle::State_On : QStyle::State_Off);

        if ((d->pressedControl == QStyle::SC_GroupBoxCheckBox

            || d->pressedControl == QStyle::SC_GroupBoxLabel) && (d->hover || d->overCheckBox))

            option->state |= QStyle::State_Sunken;

    }

    if (!option->palette.isBrushSet(isEnabled() ? QPalette::Active : 

                                    QPalette::Disabled, QPalette::WindowText))

        option->textColor = QColor(style()->styleHint(QStyle::SH_GroupBox_TextLabelColor,

                                   option, this));

    if (!d->title.isEmpty())

        option->subControls |= QStyle::SC_GroupBoxLabel;

}

void QGroupBoxPrivate::click()

{

    Q_Q(QGroupBox);

    QPointer<QGroupBox> guard(q);

    q->setChecked(!checked);

    if (!guard)

        return;

    emit q->clicked(checked);

}

/*!

    \class QGroupBox

    \brief The QGroupBox widget provides a group box frame with a title.

    \ingroup organizers

    \ingroup geomanagement

    A group box provides a frame, a title and a keyboard shortcut, and

    displays various other widgets inside itself. The title is on top,

    the keyboard shortcut moves keyboard focus to one of the group

    box's child widgets.

    QGroupBox also lets you set the \l title (normally set in the

    constructor) and the title's \l alignment. Group boxes can be

    \l checkable; child widgets in checkable group boxes are enabled or

    disabled depending on whether or not the group box is \l checked.

    You can minimize the space consumption of a group box by enabling

    the \l flat property. In most \l{QStyle}{styles}, enabling this

    property results in the removal of the left, right and bottom

    edges of the frame.

    QGroupBox doesn't automatically lay out the child widgets (which

    are often \l{QCheckBox}es or \l{QRadioButton}s but can be any

    widgets). The following example shows how we can set up a

    QGroupBox with a layout:

    \snippet examples/widgets/groupbox/window.cpp 2

    \table 100%

    \row \o \inlineimage windowsxp-groupbox.png Screenshot of a Windows XP style group box

         \o \inlineimage macintosh-groupbox.png Screenshot of a Macintosh style group box

         \o \inlineimage plastique-groupbox.png Screenshot of a Plastique style group box

    \row \o A \l{Windows XP Style Widget Gallery}{Windows XP style} group box.

         \o A \l{Macintosh Style Widget Gallery}{Macintosh style} group box.

         \o A \l{Plastique Style Widget Gallery}{Plastique style} group box.

    \endtable

    \sa QButtonGroup, {Group Box Example}

*/

/*!

    Constructs a group box widget with the given \a parent but with no title.

*/

QGroupBox::QGroupBox(QWidget *parent)

    : QWidget(*new QGroupBoxPrivate, parent, 0)

{

    Q_D(QGroupBox);

    d->init();

}

/*!

    Constructs a group box with the given \a title and \a parent.

*/

QGroupBox::QGroupBox(const QString &title, QWidget *parent)

    : QWidget(*new QGroupBoxPrivate, parent, 0)

{

    Q_D(QGroupBox);

    d->init();

    setTitle(title);

}

/*!

    Destroys the group box.

*/

QGroupBox::~QGroupBox()

{

}

void QGroupBoxPrivate::init()

{

    Q_Q(QGroupBox);

    align = Qt::AlignLeft;

#ifndef QT_NO_SHORTCUT

    shortcutId = 0;

#endif

    flat = false;

    checkable = false;

    checked = true;

    hover = false;

    overCheckBox = false;

    pressedControl = QStyle::SC_None;

    calculateFrame();

    q->setSizePolicy(QSizePolicy(QSizePolicy::Preferred, QSizePolicy::Preferred, 

                     QSizePolicy::GroupBox));

}

void QGroupBox::setTitle(const QString &title)

{

    Q_D(QGroupBox);

    if (d->title == title)                                // no change

        return;

    d->title = title;

#ifndef QT_NO_SHORTCUT

    releaseShortcut(d->shortcutId);

    d->shortcutId = grabShortcut(QKeySequence::mnemonic(title));

#endif

    d->calculateFrame();

    update();

    updateGeometry();

#ifndef QT_NO_ACCESSIBILITY

    QAccessible::updateAccessibility(this, 0, QAccessible::NameChanged);

#endif

}

/*!

    \property QGroupBox::title

    \brief the group box title text

    The group box title text will have a keyboard shortcut if the title

    contains an ampersand ('&') followed by a letter.

    \snippet doc/src/snippets/code/src_gui_widgets_qgroupbox.cpp 0

    In the example above, \key Alt+U moves the keyboard focus to the

    group box. See the \l {QShortcut#mnemonic}{QShortcut}

    documentation for details (to display an actual ampersand, use

    '&&').

    There is no default title text.

    \sa alignment

*/

QString QGroupBox::title() const

{

    Q_D(const QGroupBox);

    return d->title;

}

/*!

    \property QGroupBox::alignment

    \brief the alignment of the group box title.

    Most styles place the title at the top of the frame. The horizontal

    alignment of the title can be specified using single values from

    the following list:

    \list

    \i Qt::AlignLeft aligns the title text with the left-hand side of the group box.

    \i Qt::AlignRight aligns the title text with the right-hand side of the group box.

    \i Qt::AlignHCenter aligns the title text with the horizontal center of the group box.

    \endlist

    The default alignment is Qt::AlignLeft.

    \sa Qt::Alignment

*/

Qt::Alignment QGroupBox::alignment() const

{

    Q_D(const QGroupBox);

    return QFlag(d->align);

}

void QGroupBox::setAlignment(int alignment)

{

    Q_D(QGroupBox);

    d->align = alignment;

    updateGeometry();

    update();

}

/*! \reimp

*/

void QGroupBox::resizeEvent(QResizeEvent *e)

{

    QWidget::resizeEvent(e);

}

/*! \reimp

*/

void QGroupBox::paintEvent(QPaintEvent *)

{

    QStylePainter paint(this);

    QStyleOptionGroupBox option;

    initStyleOption(&option);

    paint.drawComplexControl(QStyle::CC_GroupBox, option);

}

/*! \reimp  */

bool QGroupBox::event(QEvent *e)

{

    Q_D(QGroupBox);

#ifndef QT_NO_SHORTCUT

    if (e->type() == QEvent::Shortcut) {

        QShortcutEvent *se = static_cast<QShortcutEvent *>(e);

        if (se->shortcutId() == d->shortcutId) {

            if (!isCheckable()) {

                d->_q_fixFocus(Qt::ShortcutFocusReason);

            } else {

                d->click();

                setFocus(Qt::ShortcutFocusReason);

            }

            return true;

        }

    }

#endif

    QStyleOptionGroupBox box;

    initStyleOption(&box);

    switch (e->type()) {

    case QEvent::HoverEnter:

    case QEvent::HoverMove: {

        QStyle::SubControl control = style()->hitTestComplexControl(QStyle::CC_GroupBox, &box,

                                                                    static_cast<QHoverEvent *>(e)->pos(),

                                                                    this);

        bool oldHover = d->hover;

        d->hover = d->checkable && (control == QStyle::SC_GroupBoxLabel || control == QStyle::SC_GroupBoxCheckBox);

        if (oldHover != d->hover) {

            QRect rect = style()->subControlRect(QStyle::CC_GroupBox, &box, QStyle::SC_GroupBoxCheckBox, this)

                         | style()->subControlRect(QStyle::CC_GroupBox, &box, QStyle::SC_GroupBoxLabel, this);

            update(rect);

        }

        return true;

    }

    case QEvent::HoverLeave:

        d->hover = false;

        if (d->checkable) {

            QRect rect = style()->subControlRect(QStyle::CC_GroupBox, &box, QStyle::SC_GroupBoxCheckBox, this)

                         | style()->subControlRect(QStyle::CC_GroupBox, &box, QStyle::SC_GroupBoxLabel, this);

            update(rect);

        }

        return true;

    case QEvent::KeyPress: {

        QKeyEvent *k = static_cast<QKeyEvent*>(e);

        if (!k->isAutoRepeat() && (k->key() == Qt::Key_Select || k->key() == Qt::Key_Space)) {

            d->pressedControl = QStyle::SC_GroupBoxCheckBox;

            update(style()->subControlRect(QStyle::CC_GroupBox, &box, QStyle::SC_GroupBoxCheckBox, this));

            return true;

        }

        break;

    }

    case QEvent::KeyRelease: {

        QKeyEvent *k = static_cast<QKeyEvent*>(e);

        if (!k->isAutoRepeat() && (k->key() == Qt::Key_Select || k->key() == Qt::Key_Space)) {

            bool toggle = (d->pressedControl == QStyle::SC_GroupBoxLabel

                           || d->pressedControl == QStyle::SC_GroupBoxCheckBox);

            d->pressedControl = QStyle::SC_None;

            if (toggle)

                d->click();

            return true;

        }

        break;

    }

    default:

        break;

    }

    return QWidget::event(e);

}

/*!\reimp */

void QGroupBox::childEvent(QChildEvent *c)

{

    Q_D(QGroupBox);

    if (c->type() != QEvent::ChildAdded || !c->child()->isWidgetType())

        return;

    QWidget *w = (QWidget*)c->child();

    if (d->checkable) {

        if (d->checked) {

            if (!w->testAttribute(Qt::WA_ForceDisabled))

                w->setEnabled(true);

        } else {

            if (w->isEnabled()) {

                w->setEnabled(false);

                w->setAttribute(Qt::WA_ForceDisabled, false);

            }

        }

    }

}

/*!

    \internal

    This private slot finds a widget in this group box that can accept

    focus, and gives the focus to that widget.

*/

void QGroupBoxPrivate::_q_fixFocus(Qt::FocusReason reason)

{

    Q_Q(QGroupBox);

    QWidget *fw = q->focusWidget();

    if (!fw || fw == q) {

        QWidget * best = 0;

        QWidget * candidate = 0;

        QWidget * w = q;

        while ((w = w->nextInFocusChain()) != q) {

            if (q->isAncestorOf(w) && (w->focusPolicy() & Qt::TabFocus) == Qt::TabFocus && w->isVisibleTo(q)) {

                if (!best && qobject_cast<QRadioButton*>(w) && ((QRadioButton*)w)->isChecked())

                    // we prefer a checked radio button or a widget that

                    // already has focus, if there is one

                    best = w;

                else

                    if (!candidate)

                        // but we'll accept anything that takes focus

                        candidate = w;

            }

        }

        if (best)

            fw = best;

        else if (candidate)

                fw = candidate;

    }

    if (fw)

        fw->setFocus(reason);

}

/*

    Sets the right frame rect depending on the title.

*/

void QGroupBoxPrivate::calculateFrame()

{

    Q_Q(QGroupBox);

    QStyleOptionGroupBox box;

    q->initStyleOption(&box);

    QRect contentsRect = q->style()->subControlRect(QStyle::CC_GroupBox, &box, QStyle::SC_GroupBoxContents, q);

    q->setContentsMargins(contentsRect.left() - box.rect.left(), contentsRect.top() - box.rect.top(),

                          box.rect.right() - contentsRect.right(), box.rect.bottom() - contentsRect.bottom());

    setLayoutItemMargins(QStyle::SE_GroupBoxLayoutItem, &box);

}

/*! \reimp

 */

void QGroupBox::focusInEvent(QFocusEvent *fe)

{ // note no call to super

    Q_D(QGroupBox);

    if (focusPolicy() == Qt::NoFocus) {

        d->_q_fixFocus(fe->reason());

    } else {

        QWidget::focusInEvent(fe);

    }

}

/*!

  \reimp

*/

QSize QGroupBox::minimumSizeHint() const

{

    Q_D(const QGroupBox);

    QStyleOptionGroupBox option;

    initStyleOption(&option);

    QFontMetrics metrics(fontMetrics());

    int baseWidth = metrics.width(d->title) + metrics.width(QLatin1Char(' '));

    int baseHeight = metrics.height();

    if (d->checkable) {

        baseWidth += style()->pixelMetric(QStyle::PM_IndicatorWidth);

        baseWidth += style()->pixelMetric(QStyle::PM_CheckBoxLabelSpacing);

        baseHeight = qMax(baseHeight, style()->pixelMetric(QStyle::PM_IndicatorHeight));

    }

    QSize size = style()->sizeFromContents(QStyle::CT_GroupBox, &option, QSize(baseWidth, baseHeight), this);

    return size.expandedTo(QWidget::minimumSizeHint());

}

/*!

    \property QGroupBox::flat

    \brief whether the group box is painted flat or has a frame

    A group box usually consists of a surrounding frame with a title

    at the top. If this property is enabled, only the top part of the frame is

    drawn in most styles; otherwise the whole frame is drawn.

    By default, this property is disabled; i.e. group boxes are not flat unless

    explicitly specified.

    \bold{Note:} In some styles, flat and non-flat group boxes have similar

    representations and may not be as distinguishable as they are in other

    styles.

    \sa title

*/

bool QGroupBox::isFlat() const

{

    Q_D(const QGroupBox);

    return d->flat;

}