qheaderview.cpp

奇趣公司比较新的qt/emd版本

    Q_D(const QHeaderView);
    return d->sortIndicatorOrder;
}

/*!
    \property QHeaderView::stretchLastSection
    \brief whether the last visible section in the header takes up all the available space

    The default value is false.

    \bold{Note:} The horizontal headers provided by QTreeView are configured with
    this property set to true, ensuring that the view does not waste any of the
    space assigned to it for its header.

    \bold{Also note:} If the value is set to true, this property will override the
    resize mode set on the last section in the header.

    \sa setResizeMode()
*/
bool QHeaderView::stretchLastSection() const
{
    Q_D(const QHeaderView);
    return d->stretchLastSection;
}

void QHeaderView::setStretchLastSection(bool stretch)
{
    Q_D(QHeaderView);
    d->stretchLastSection = stretch;
    if (d->state != QHeaderViewPrivate::NoState)
        return;
    if (stretch)
        resizeSections();
    else if (count())
        resizeSection(count() - 1, d->defaultSectionSize);
}

/*!
    \since 4.2
    \property QHeaderView::cascadingSectionResizes
    \brief whether interactive resizing will be cascaded to the following sections once the
    section being resized by the user has reached its minimum size

    This property only affects sections that have \l Interactive as the resize mode.

    The default value is false.

    \sa setResizeMode()
*/
bool QHeaderView::cascadingSectionResizes() const
{
    Q_D(const QHeaderView);
    return d->cascadingResizing;
}

void QHeaderView::setCascadingSectionResizes(bool enable)
{
    Q_D(QHeaderView);
    d->cascadingResizing = enable;
}

/*!
    \property QHeaderView::defaultSectionSize
    \brief the default size of the header sections before resizing.

    This property only affects sections that have \l Interactive or \l Fixed as the resize mode.

    \sa setResizeMode() minimumSectionSize
*/
int QHeaderView::defaultSectionSize() const
{
    Q_D(const QHeaderView);
    return d->defaultSectionSize;
}

void QHeaderView::setDefaultSectionSize(int size)
{
    Q_D(QHeaderView);
    d->defaultSectionSize = size;
    d->forceInitializing = true;
}

/*!
    \since 4.2
    \property QHeaderView::minimumSectionSize
    \brief the minimum size of the header sections.

    The minimum section size is the smallest section size allowed.
    If the minimum section size is set to -1, QHeaderView will use the
    maximum of the \l{QApplication::globalStrut()}{global strut}
    or the \l{fontMetrics()}{font metrics} size.

    This property is honored by all \l{ResizeMode}{resize modes}.

    \sa setResizeMode() defaultSectionSize
*/
int QHeaderView::minimumSectionSize() const
{
    Q_D(const QHeaderView);
    if (d->minimumSectionSize == -1) {
        QSize strut = QApplication::globalStrut();
        int margin = style()->pixelMetric(QStyle::PM_HeaderMargin, 0, this);
        if (d->orientation == Qt::Horizontal)
            return qMax(strut.width(), (fontMetrics().maxWidth() + margin));
        return qMax(strut.height(), (fontMetrics().lineSpacing() + margin));
    }
    return d->minimumSectionSize;
}

void QHeaderView::setMinimumSectionSize(int size)
{
    Q_D(QHeaderView);
    d->minimumSectionSize = size;
}

/*!
    \since 4.1
    \property QHeaderView::defaultAlignment
    \brief the default alignment of the text in each header section
*/

Qt::Alignment QHeaderView::defaultAlignment() const
{
    Q_D(const QHeaderView);
    return d->defaultAlignment;
}

void QHeaderView::setDefaultAlignment(Qt::Alignment alignment)
{
    Q_D(QHeaderView);
    if (d->defaultAlignment == alignment)
        return;

    d->defaultAlignment = alignment;
    d->viewport->update();
}

/*!
    \internal
*/
void QHeaderView::doItemsLayout()
{
    initializeSections();
    QAbstractItemView::doItemsLayout();
}

/*!
  Returns true if sections in the header has been moved;
  otherwise returns false;

  \sa moveSection()
*/
bool QHeaderView::sectionsMoved() const
{
    Q_D(const QHeaderView);
    return !d->visualIndices.isEmpty();
}

/*!
    \since 4.1

    Returns true if sections in the header has been hidden;
    otherwise returns false;

    \sa setSectionHidden()
*/
bool QHeaderView::sectionsHidden() const
{
    Q_D(const QHeaderView);
    return !d->hiddenSectionSize.isEmpty();
}

#ifndef QT_NO_DATASTREAM
/*!
    \since 4.3

    Saves the current state of this header view.

    To restore the saved state, pass the return value to restoreState().

    \sa restoreState()
*/
QByteArray QHeaderView::saveState() const
{
    Q_D(const QHeaderView);
    QByteArray data;
    QDataStream stream(&data, QIODevice::WriteOnly);
    stream << QHeaderViewPrivate::VersionMarker;
    stream << 0; // current version is 0
    d->write(stream);
    return data;
}

/*!
    \since 4.3
    Restores the \a state of this header view.
    This function returns \c true if the state was
    restored, otherwise returns false.

    \sa saveState()
*/
bool QHeaderView::restoreState(const QByteArray &state)
{
    Q_D(QHeaderView);
    if (state.isEmpty())
        return false;
    QByteArray data = state;
    QDataStream stream(&data, QIODevice::ReadOnly);
    int marker;
    int ver;
    stream >> marker;
    stream >> ver;
    if (stream.status() != QDataStream::Ok
        || marker != QHeaderViewPrivate::VersionMarker
        || ver != 0) // current version is 0
        return false;
    return d->read(stream);
}
#endif

/*!
  \reimp
*/
void QHeaderView::reset()
{
    QAbstractItemView::reset();
    // it would be correct to call clear, but some apps rely
    // on the header keeping the sections, even after calling reset
    //d->clear();
    initializeSections();
}

/*!
  Updates the changed header sections with the given \a orientation, from
  \a logicalFirst to \a logicalLast inclusive.
*/
void QHeaderView::headerDataChanged(Qt::Orientation orientation, int logicalFirst, int logicalLast)
{
    Q_D(QHeaderView);
    if (d->orientation != orientation)
        return;

    if (logicalFirst < 0 || logicalLast < 0 || logicalFirst >= count() || logicalLast >= count())
        return;

    d->invalidateCachedSizeHint();

    if (orientation == Qt::Horizontal) {
        int left = sectionViewportPosition(logicalFirst);
        int right = sectionViewportPosition(logicalLast);
        right += sectionSize(logicalLast);
        d->viewport->update(left, 0, right - left, d->viewport->height());
    } else {
        int top = sectionViewportPosition(logicalFirst);
        int bottom = sectionViewportPosition(logicalLast);
        bottom += sectionSize(logicalLast);
        d->viewport->update(0, top, d->viewport->width(), bottom - top);
    }
}

/*!
    \internal
    \since 4.2

    Updates the section specified by the given \a logicalIndex.
*/

void QHeaderView::updateSection(int logicalIndex)
{
    Q_D(QHeaderView);
    if (d->orientation == Qt::Horizontal)
        d->viewport->update(QRect(sectionViewportPosition(logicalIndex),
                                  0, sectionSize(logicalIndex), d->viewport->height()));
    else
        d->viewport->update(QRect(0, sectionViewportPosition(logicalIndex),
                                  d->viewport->width(), sectionSize(logicalIndex)));
}

/*!
    Resizes the sections according to their size hints. You should not
    normally need to call this function.
*/

void QHeaderView::resizeSections()
{
    Q_D(QHeaderView);
    if (d->hasAutoResizeSections())
        d->resizeSections(Interactive, false); // no global resize mode
}

/*!
    This slot is called when sections are inserted into the \a parent,
    \a logicalFirst and \a logicalLast indexes signify where the new
    sections are inserted.

    \a logicalFirst and \a logicalLast will be the same if just one
    section is inserted.
*/

void QHeaderView::sectionsInserted(const QModelIndex &parent,
                                   int logicalFirst, int logicalLast)
{
    Q_D(QHeaderView);
    if (parent != d->root)
        return; // we only handle changes in the top level
    int oldCount = d->sectionCount;

    d->invalidateCachedSizeHint();

    // add the new sections
    int insertAt = 0;
    for (int spanStart = 0; insertAt < d->sectionSpans.count() && spanStart < logicalFirst; ++insertAt)
        spanStart += d->sectionSpans.at(insertAt).count;
    
    int insertCount = logicalLast - logicalFirst + 1;
    d->sectionCount += insertCount;
        
    if (d->sectionSpans.isEmpty() || insertAt >= d->sectionSpans.count()) {
        int insertLength = d->defaultSectionSize * insertCount;
        d->length += insertLength;
        QHeaderViewPrivate::SectionSpan span(insertLength, insertCount, d->globalResizeMode);
        d->sectionSpans.append(span);
    } else if ((d->sectionSpans.at(insertAt).sectionSize() == d->defaultSectionSize)
               && d->sectionSpans.at(insertAt).resizeMode == d->globalResizeMode) {
        // add the new sections to an existing span
        int insertLength = d->sectionSpans.at(insertAt).sectionSize() * insertCount;
        d->length += insertLength;
        d->sectionSpans[insertAt].size += insertLength;
        d->sectionSpans[insertAt].count += insertCount;
    } else {
        // separate them out into their own span
        int insertLength = d->defaultSectionSize * insertCount;
        d->length += insertLength;
        QHeaderViewPrivate::SectionSpan span(insertLength, insertCount, d->globalResizeMode);
        d->sectionSpans.insert(insertAt, span);
    }
    
    // update resize mode section counts
    if (d->globalResizeMode == Stretch)
        d->stretchSections = d->sectionCount;
    else if (d->globalResizeMode == ResizeToContents)
        d->contentsSections = d->sectionCount;

    // insert new sections in sectionsHidden
    if (!d->sectionHidden.isEmpty()) {
        QBitArray sectionHidden(d->sectionHidden);
        sectionHidden.resize(sectionHidden.count() + insertCount);
        //sectionHidden.fill(false, logicalFirst, logicalLast + 1);
        for (int i = logicalFirst; i <= logicalLast; ++i)
            sectionHidden.setBit(i, false);
        for (int j = logicalLast + 1; j < sectionHidden.count(); ++j)
            sectionHidden.setBit(j, d->sectionHidden.testBit(j - insertCount));
        d->sectionHidden = sectionHidden;
    }

    // clear selection cache
    d->sectionSelected.clear();

    // update mapping
    if (!d->visualIndices.isEmpty() && !d->logicalIndices.isEmpty()) {
        Q_ASSERT(d->visualIndices.count() == d->logicalIndices.count());
        int mappingCount = d->visualIndices.count();
        for (int i = 0; i < mappingCount; ++i) {
            if (d->visualIndices.at(i) >= logicalFirst)
               d->visualIndices[i] += insertCount;
            if (d->logicalIndices.at(i) >= logicalFirst)
                d->logicalIndices[i] += insertCount;
        }
        for (int j = logicalFirst; j <= logicalLast; ++j) {
            d->visualIndices.insert(j, j);
            d->logicalIndices.insert(j, j);
        }
    }

    resizeSections();
    emit sectionCountChanged(oldCount, count());

    // if the new sections were not updated by resizing, we need to update now
    if (!d->hasAutoResizeSections())
        d->viewport->update();
}

/*!
    This slot is called when sections are removed from the \a parent,
    \a logicalFirst and \a logicalLast signify where the sections are removed
    from. (\a logicalFirst and \a logicalLast will be the same if just one section
    is removed.)
*/

void QHeaderView::sectionsAboutToBeRemoved(const QModelIndex &parent,
                                           int logicalFirst, int logicalLast)
{
    Q_UNUSED(parent);
    Q_UNUSED(logicalFirst);
    Q_UNUSED(logicalLast);
}

void QHeaderViewPrivate::_q_sectionsRemoved(const QModelIndex &parent,
                                            int logicalFirst, int logicalLast)
{
    Q_Q(QHeaderView);
    if (parent != root)
        return; // we only handle changes in the top level
    if (qMin(logicalFirst, logicalLast) < 0
        || qMax(logicalLast, logicalFirst) >= sectionCount)
        return;
    int oldCount = q->count();
    int changeCount = logicalLast - logicalFirst + 1;

    // remove sections in sectionsHidden
    if (!sectionHidden.isEmpty()) {
        const int newsize = qMin(sectionCount - changeCount, sectionHidden.size());
        QBitArray newSectionHidden(newsize);
        for(int j = 0, k = 0; j < sectionHidden.size(); ++j) {
            const int logical = q->logicalIndex(j);
            if (logical < logicalFirst || logical > logicalLast) {
                newSectionHidden[k++] = sectionHidden[j];