qgroupbox.cpp

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#include "qgroupbox.h"
 
#include "qapplication.h"
#include "qbitmap.h"
#include "qdrawutil.h"
#include "qevent.h"
#include "qlayout.h"
#if QT_CONFIG(radiobutton)
#include "qradiobutton.h"
#endif
#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;
};
 
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;
 
    option->state.setFlag(QStyle::State_MouseOver, d->hover);
    if (d->flat)
        option->features |= QStyleOptionFrame::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);
}
 
QGroupBox::QGroupBox(QWidget *parent)
    : QWidget(*new QGroupBoxPrivate, parent, { })
{
    Q_D(QGroupBox);
    d->init();
}
 
QGroupBox::QGroupBox(const QString &title, QWidget *parent)
    : QGroupBox(parent)
{
    setTitle(title);
}
 
 
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
    QAccessibleEvent event(this, QAccessible::NameChanged);
    QAccessible::updateAccessibility(&event);
#endif
}
 
QString QGroupBox::title() const
{
    Q_D(const QGroupBox);
    return d->title;
}
 
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();
}
 
void QGroupBox::resizeEvent(QResizeEvent *e)
{
    QWidget::resizeEvent(e);
}
 
void QGroupBox::paintEvent(QPaintEvent *)
{
    QStylePainter paint(this);
    QStyleOptionGroupBox option;
    initStyleOption(&option);
    paint.drawComplexControl(QStyle::CC_GroupBox, option);
}
 
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)->position().toPoint(),
                                                                    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);
}
 
void QGroupBox::childEvent(QChildEvent *c)
{
    Q_D(QGroupBox);
    /*
        Children might have been enabled after being added to the group box, in which case
        the childEvent handler ran too early, and we need to disabled children again.
    */
    if (!(c->added() || c->polished()) || !c->child()->isWidgetType())
        return;
    QWidget *w = static_cast<QWidget*>(c->child());
    if (w->isWindow())
        return;
    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);
            }
        }
    }
}
 
 
void QGroupBoxPrivate::_q_fixFocus(Qt::FocusReason reason)
{
    Q_Q(QGroupBox);
    QWidget *fw = q->focusWidget();
    if (!fw || fw == q) {
        QWidget * best = nullptr;
        QWidget * candidate = nullptr;
        QWidget * w = q;
        while ((w = w->nextInFocusChain()) != q) {
            if (q->isAncestorOf(w) && (w->focusPolicy() & Qt::TabFocus) == Qt::TabFocus && w->isVisibleTo(q)) {
#if QT_CONFIG(radiobutton)
                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
#endif
                    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);
}
 
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);
    }
}
 
 
QSize QGroupBox::minimumSizeHint() const
{
    Q_D(const QGroupBox);
    QStyleOptionGroupBox option;
    initStyleOption(&option);
 
    QFontMetrics metrics(fontMetrics());
 
    int baseWidth = metrics.horizontalAdvance(d->title) + metrics.horizontalAdvance(QLatin1Char(' '));
    int baseHeight = metrics.height();
    if (d->checkable) {
        baseWidth += style()->pixelMetric(QStyle::PM_IndicatorWidth, &option);
        baseWidth += style()->pixelMetric(QStyle::PM_CheckBoxLabelSpacing, &option);
        baseHeight = qMax(baseHeight, style()->pixelMetric(QStyle::PM_IndicatorHeight, &option));
    }
 
    QSize size = style()->sizeFromContents(QStyle::CT_GroupBox, &option, QSize(baseWidth, baseHeight), this);
    return size.expandedTo(QWidget::minimumSizeHint());
}
 
bool QGroupBox::isFlat() const
{
    Q_D(const QGroupBox);
    return d->flat;
}
 
void QGroupBox::setFlat(bool b)
{
    Q_D(QGroupBox);
    if (d->flat == b)
        return;
    d->flat = b;
    updateGeometry();
    update();
}
 
 
void QGroupBox::setCheckable(bool checkable)
{
    Q_D(QGroupBox);
 
    bool wasCheckable = d->checkable;
    d->checkable = checkable;
 
    if (checkable) {
        setChecked(true);
        if (!wasCheckable) {
            setFocusPolicy(Qt::StrongFocus);
            d->_q_setChildrenEnabled(true);
            updateGeometry();
        }
    } else {
        if (wasCheckable) {
            setFocusPolicy(Qt::NoFocus);
            d->_q_setChildrenEnabled(true);
            updateGeometry();
        }
        d->_q_setChildrenEnabled(true);
    }
 
    if (wasCheckable != checkable) {
        d->calculateFrame();
        update();
    }
}
 
bool QGroupBox::isCheckable() const
{
    Q_D(const QGroupBox);
    return d->checkable;
}
 
 
bool QGroupBox::isChecked() const
{
    Q_D(const QGroupBox);
    return d->checkable && d->checked;
}
 
 
void QGroupBox::setChecked(bool b)
{
    Q_D(QGroupBox);
    if (d->checkable && b != d->checked) {
        update();
        d->checked = b;
        d->_q_setChildrenEnabled(b);
#ifndef QT_NO_ACCESSIBILITY
        QAccessible::State st;
        st.checked = true;
        QAccessibleStateChangeEvent e(this, st);
        QAccessible::updateAccessibility(&e);
#endif
        emit toggled(b);
    }
}
 
/*
  sets all children of the group box except the qt_groupbox_checkbox
  to either disabled/enabled
*/
void QGroupBoxPrivate::_q_setChildrenEnabled(bool b)
{
    Q_Q(QGroupBox);
    for (QObject *o : q->children()) {
        if (o->isWidgetType()) {
            QWidget *w = static_cast<QWidget *>(o);
            if (b) {
                if (!w->testAttribute(Qt::WA_ForceDisabled))
                    w->setEnabled(true);
            } else {
                if (w->isEnabled()) {
                    w->setEnabled(false);
                    w->setAttribute(Qt::WA_ForceDisabled, false);
                }
            }
        }
    }
}
 
void QGroupBox::changeEvent(QEvent *ev)
{
    Q_D(QGroupBox);
    if (ev->type() == QEvent::EnabledChange) {
        if (d->checkable && isEnabled()) {
            // we are being enabled - disable children
            if (!d->checked)
                d->_q_setChildrenEnabled(false);
        }
    } else if (ev->type() == QEvent::FontChange
#ifdef Q_OS_MAC
               || ev->type() == QEvent::MacSizeChange
#endif
               || ev->type() == QEvent::StyleChange) {
        d->calculateFrame();
    }
    QWidget::changeEvent(ev);
}
 
void QGroupBox::mousePressEvent(QMouseEvent *event)
{
    if (event->button() != Qt::LeftButton) {
        event->ignore();
        return;
    }
 
    Q_D(QGroupBox);
    QStyleOptionGroupBox box;
    initStyleOption(&box);
    d->pressedControl = style()->hitTestComplexControl(QStyle::CC_GroupBox, &box,
                                                       event->position().toPoint(), this);
    if (d->checkable && (d->pressedControl & (QStyle::SC_GroupBoxCheckBox | QStyle::SC_GroupBoxLabel))) {
        d->overCheckBox = true;
        update(style()->subControlRect(QStyle::CC_GroupBox, &box, QStyle::SC_GroupBoxCheckBox, this));
    } else {
        event->ignore();
    }
}
 
void QGroupBox::mouseMoveEvent(QMouseEvent *event)
{
    Q_D(QGroupBox);
    QStyleOptionGroupBox box;
    initStyleOption(&box);
    QStyle::SubControl pressed = style()->hitTestComplexControl(QStyle::CC_GroupBox, &box,
                                                                event->position().toPoint(), this);
    bool oldOverCheckBox = d->overCheckBox;
    d->overCheckBox = (pressed == QStyle::SC_GroupBoxCheckBox || pressed == QStyle::SC_GroupBoxLabel);
    if (d->checkable && (d->pressedControl == QStyle::SC_GroupBoxCheckBox || d->pressedControl == QStyle::SC_GroupBoxLabel)
        && (d->overCheckBox != oldOverCheckBox))
        update(style()->subControlRect(QStyle::CC_GroupBox, &box, QStyle::SC_GroupBoxCheckBox, this));
 
    event->ignore();
}
 
void QGroupBox::mouseReleaseEvent(QMouseEvent *event)
{
    if (event->button() != Qt::LeftButton) {
        event->ignore();
        return;
    }
 
    Q_D(QGroupBox);
    if (!d->overCheckBox) {
        event->ignore();
        return;
    }
    QStyleOptionGroupBox box;
    initStyleOption(&box);
    QStyle::SubControl released = style()->hitTestComplexControl(QStyle::CC_GroupBox, &box,
                                                                 event->position().toPoint(), this);
    bool toggle = d->checkable && (released == QStyle::SC_GroupBoxLabel
                                   || released == QStyle::SC_GroupBoxCheckBox);
    d->pressedControl = QStyle::SC_None;
    d->overCheckBox = false;
    if (toggle)
        d->click();
    else if (d->checkable)
        update(style()->subControlRect(QStyle::CC_GroupBox, &box, QStyle::SC_GroupBoxCheckBox, this));
}
 
QT_END_NAMESPACE
 
#include "moc_qgroupbox.cpp"