qabstractslider.cpp

奇趣公司比较新的qt/emd版本

        else
            emit sliderReleased();
    }

    if (!down && d->position != d->value)
        triggerAction(SliderMove);
}

bool QAbstractSlider::isSliderDown() const
{
    Q_D(const QAbstractSlider);
    return d->pressed;
}


/*!
    \property QAbstractSlider::sliderPosition
    \brief the current slider position

    If \l tracking is enabled (the default), this is identical to \l value.
*/
void QAbstractSlider::setSliderPosition(int position)
{
    Q_D(QAbstractSlider);
    position = d->bound(position);
    if (position == d->position)
        return;
    d->position = position;
    if (!d->tracking)
        update();
    if (d->pressed)
        emit sliderMoved(position);
    if (d->tracking && !d->blocktracking)
        triggerAction(SliderMove);
}

int QAbstractSlider::sliderPosition() const
{
    Q_D(const QAbstractSlider);
    return d->position;
}


/*!
    \property QAbstractSlider::value
    \brief the slider's current value

    The slider forces the value to be within the legal range: \l
    minimum <= \c value <= \l maximum.

    Changing the value also changes the \l sliderPosition.
*/


int QAbstractSlider::value() const
{
    Q_D(const QAbstractSlider);
    return d->value;
}

void QAbstractSlider::setValue(int value)
{
    Q_D(QAbstractSlider);
    value = d->bound(value);
    if (d->value == value && d->position == value)
        return;
    d->value = value;
    if (d->position != value) {
        d->position = value;
        if (d->pressed)
            emit sliderMoved((d->position = value));
    }
#ifndef QT_NO_ACCESSIBILITY
    QAccessible::updateAccessibility(this, 0, QAccessible::ValueChanged);
#endif
    sliderChange(SliderValueChange);
    emit valueChanged(value);
}

/*!
    \property QAbstractSlider::invertedAppearance
    \brief whether or not a slider shows its values inverted.

    If this property is false (the default), the minimum and maximum will
    be shown in its classic position for the inherited widget. If the
    value is true, the minimum and maximum appear at their opposite location.

    Note: This property makes most sense for sliders and dials. For
    scroll bars, the visual effect of the scroll bar subcontrols depends on
    whether or not the styles understand inverted appearance; most styles
    ignore this property for scroll bars.
*/

bool QAbstractSlider::invertedAppearance() const
{
    Q_D(const QAbstractSlider);
    return d->invertedAppearance;
}

void QAbstractSlider::setInvertedAppearance(bool invert)
{
    Q_D(QAbstractSlider);
    d->invertedAppearance = invert;
    update();
}


/*!
    \property QAbstractSlider::invertedControls
    \brief whether or not the slider inverts its wheel and key events.

    If this property is false, scrolling the mouse wheel "up" and using keys
    like page up will increase the slider's value towards its maximum. Otherwise
    pressing page up will move value towards the slider's minimum.
*/


bool QAbstractSlider::invertedControls() const
{
    Q_D(const QAbstractSlider);
    return d->invertedControls;
}

void QAbstractSlider::setInvertedControls(bool invert)
{
    Q_D(QAbstractSlider);
    d->invertedControls = invert;
}

/*!  Triggers a slider \a action.  Possible actions are \l
  SliderSingleStepAdd, \l SliderSingleStepSub, \l SliderPageStepAdd,
  \l SliderPageStepSub, \l SliderToMinimum, \l SliderToMaximum, and \l
  SliderMove.

  \sa actionTriggered()
 */
void QAbstractSlider::triggerAction(SliderAction action)
{
    Q_D(QAbstractSlider);
    d->blocktracking = true;
    switch (action) {
    case SliderSingleStepAdd:
        setSliderPosition(d->value + d->singleStep);
        break;
    case SliderSingleStepSub:
        setSliderPosition(d->value - d->singleStep);
        break;
    case SliderPageStepAdd:
        setSliderPosition(d->value + d->pageStep);
        break;
    case SliderPageStepSub:
        setSliderPosition(d->value - d->pageStep);
        break;
    case SliderToMinimum:
        setSliderPosition(d->minimum);
        break;
    case SliderToMaximum:
        setSliderPosition(d->maximum);
        break;
    case SliderMove:
    case SliderNoAction:
        break;
    };
    emit actionTriggered(action);
    d->blocktracking = false;
    setValue(d->position);
}

/*!  Sets action \a action to be triggered repetitively in intervals
of \a repeatTime, after an initial delay of \a thresholdTime.

\sa triggerAction() repeatAction()
 */
void QAbstractSlider::setRepeatAction(SliderAction action, int thresholdTime, int repeatTime)
{
    Q_D(QAbstractSlider);
    if ((d->repeatAction = action) == SliderNoAction) {
        d->repeatActionTimer.stop();
    } else {
        d->repeatActionTime = repeatTime;
        d->repeatActionTimer.start(thresholdTime, this);
    }
}

/*!
  Returns the current repeat action.
  \sa setRepeatAction()
 */
QAbstractSlider::SliderAction QAbstractSlider::repeatAction() const
{
    Q_D(const QAbstractSlider);
    return d->repeatAction;
}

/*!\reimp
 */
void QAbstractSlider::timerEvent(QTimerEvent *e)
{
    Q_D(QAbstractSlider);
    if (e->timerId() == d->repeatActionTimer.timerId()) {
        if (d->repeatActionTime) { // was threshold time, use repeat time next time
            d->repeatActionTimer.start(d->repeatActionTime, this);
            d->repeatActionTime = 0;
        }
        if (d->repeatAction == SliderPageStepAdd)
            d->setAdjustedSliderPosition(d->value + d->pageStep);
        else if (d->repeatAction == SliderPageStepSub)
            d->setAdjustedSliderPosition(d->value - d->pageStep);
        else
            triggerAction(d->repeatAction);
    }
}

/*!
    Reimplement this virtual function to track slider changes such as
    \l SliderRangeChange, \l SliderOrientationChange, \l
    SliderStepsChange, or \l SliderValueChange. The default
    implementation only updates the display and ignores the \a change
    parameter.
 */
void QAbstractSlider::sliderChange(SliderChange)
{
    update();
}


/*!
    \reimp
*/
#ifndef QT_NO_WHEELEVENT
void QAbstractSlider::wheelEvent(QWheelEvent * e)
{
    Q_D(QAbstractSlider);
    e->ignore();
    if (e->orientation() != d->orientation && !rect().contains(e->pos()))
        return;

    static qreal offset = 0;
    static QAbstractSlider *offset_owner = 0;
    if (offset_owner != this){
        offset_owner = this;
        offset = 0;
    }

    int step = qMin(QApplication::wheelScrollLines() * d->singleStep, d->pageStep);
    if ((e->modifiers() & Qt::ControlModifier) || (e->modifiers() & Qt::ShiftModifier))
        step = d->pageStep;
    offset += e->delta() * step / 120;
    if (d->invertedControls)
        offset = -offset;

    if (qAbs(offset) < 1)
        return;

    int prevValue = d->value;
    d->position = d->value + int(offset); // value will be updated by triggerAction()
    triggerAction(SliderMove);
    if (prevValue == d->value) {
        offset = 0;
    } else {
        offset -= int(offset);
        e->accept();
    }
}
#endif
/*!
    \reimp
*/
void QAbstractSlider::keyPressEvent(QKeyEvent *ev)
{
    Q_D(QAbstractSlider);
    SliderAction action = SliderNoAction;
    switch (ev->key()) {
#ifdef QT_KEYPAD_NAVIGATION
        case Qt::Key_Select:
            if (QApplication::keypadNavigationEnabled())
                setEditFocus(!hasEditFocus());
            else
                ev->ignore();
            break;
        case Qt::Key_Back:
            if (QApplication::keypadNavigationEnabled() && hasEditFocus()) {
                setValue(d->origValue);
                setEditFocus(false);
            } else
                ev->ignore();
            break;
#endif

        // It seems we need to use invertedAppearance for Left and right, otherwise, things look weird.
        case Qt::Key_Left:
#ifdef QT_KEYPAD_NAVIGATION
            if (QApplication::keypadNavigationEnabled() && !hasEditFocus()) {
                ev->ignore();
                return;
            }
            if (QApplication::keypadNavigationEnabled() && d->orientation == Qt::Vertical)
                action = d->invertedControls ? SliderSingleStepSub : SliderSingleStepAdd;
            else
#endif
            action = !d->invertedAppearance ? SliderSingleStepSub : SliderSingleStepAdd;
            break;
        case Qt::Key_Right:
#ifdef QT_KEYPAD_NAVIGATION
            if (QApplication::keypadNavigationEnabled() && !hasEditFocus()) {
                ev->ignore();
                return;
            }
            if (QApplication::keypadNavigationEnabled() && d->orientation == Qt::Vertical)
                action = d->invertedControls ? SliderSingleStepAdd : SliderSingleStepSub;
            else
#endif
            action = !d->invertedAppearance ? SliderSingleStepAdd : SliderSingleStepSub;
            break;
        case Qt::Key_Up:
#ifdef QT_KEYPAD_NAVIGATION
            if (QApplication::keypadNavigationEnabled()) {
                ev->ignore();
                break;
            }
#endif
            action = d->invertedControls ? SliderSingleStepSub : SliderSingleStepAdd;
            break;
        case Qt::Key_Down:
#ifdef QT_KEYPAD_NAVIGATION
            if (QApplication::keypadNavigationEnabled()) {
                ev->ignore();
                break;
            }
#endif
            action = d->invertedControls ? SliderSingleStepAdd : SliderSingleStepSub;
            break;
        case Qt::Key_PageUp:
            action = d->invertedControls ? SliderPageStepSub : SliderPageStepAdd;
            break;
        case Qt::Key_PageDown:
            action = d->invertedControls ? SliderPageStepAdd : SliderPageStepSub;
            break;
        case Qt::Key_Home:
            action = SliderToMinimum;
            break;
        case Qt::Key_End:
            action = SliderToMaximum;
            break;
        default:
            ev->ignore();
            break;
    }
    if (action)
        triggerAction(action);
}

/*!
    \reimp
*/
void QAbstractSlider::changeEvent(QEvent *ev)
{
    Q_D(QAbstractSlider);
    switch (ev->type()) {
    case QEvent::EnabledChange:
        if (!isEnabled()) {
            d->repeatActionTimer.stop();
            setSliderDown(false);
        }
        // fall through...
    default:
        QWidget::changeEvent(ev);
    }
}

/*!
    \reimp
*/
bool QAbstractSlider::event(QEvent *e)
{
#ifdef QT_KEYPAD_NAVIGATION
    Q_D(QAbstractSlider);
    switch (e->type()) {
    case QEvent::FocusIn:
        d->origValue = d->value;
        break;
    default:
        break;
    }
#endif
    
    return QWidget::event(e);
}

/*! \fn int QAbstractSlider::minValue() const

    Use minimum() instead.
*/

/*! \fn int QAbstractSlider::maxValue() const

    Use maximum() instead.
*/

/*! \fn int QAbstractSlider::lineStep() const

    Use singleStep() instead.
*/

/*! \fn void QAbstractSlider::setMinValue(int v)

    Use setMinimum() instead.
*/

/*! \fn void QAbstractSlider::setMaxValue(int v)

    Use setMaximum() instead.
*/

/*! \fn void QAbstractSlider::setLineStep(int v)

    Use setSingleStep() instead.
*/

/*! \fn void QAbstractSlider::addPage()

    Use triggerAction(QAbstractSlider::SliderPageStepAdd) instead.
*/

/*! \fn void QAbstractSlider::subtractPage()

    Use triggerAction(QAbstractSlider::SliderPageStepSub) instead.
*/

/*! \fn void QAbstractSlider::addLine()

    Use triggerAction(QAbstractSlider::SliderSingleStepAdd) instead.
*/

/*! \fn void QAbstractSlider::subtractLine()

    Use triggerAction(QAbstractSlider::SliderSingleStepSub) instead.
*/

/*! \fn void QAbstractSlider::setSteps(int single, int page)

    Use setSingleStep(\a single) followed by setPageStep(\a page)
    instead.
*/