qheaderview.cpp

奇趣公司比较新的qt/emd版本

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#include "qheaderview.h"

#ifndef QT_NO_ITEMVIEWS
#include <qbitarray.h>
#include <qbrush.h>
#include <qdebug.h>
#include <qevent.h>
#include <qpainter.h>
#include <qscrollbar.h>
#include <qtooltip.h>
#include <qwhatsthis.h>
#include <qstyle.h>
#include <qstyleoption.h>
#include <qvector.h>
#include <qapplication.h>
#include <qvarlengtharray.h>
#include <qabstractitemdelegate.h>
#include <qvariant.h>
#include <private/qheaderview_p.h>
#include <private/qabstractitemmodel_p.h>

#ifndef QT_NO_DATASTREAM
#include <qdatastream.h>

QDataStream &operator<<(QDataStream &out, const QHeaderViewPrivate::SectionSpan &span)
{
    span.write(out);
    return out;
}

QDataStream &operator>>(QDataStream &in, QHeaderViewPrivate::SectionSpan &span)
{
    span.read(in);
    return in;
}
#endif


/*!
    \class QHeaderView

    \brief The QHeaderView class provides a header row or header column for item views.

    \ingroup model-view
    \mainclass

    A QHeaderView displays the headers used in item views such as the
    QTableView and QTreeView classes. It takes the place of
    the \c QHeader class previously used for the same purpose, but uses
    the Qt's model/view architecture for consistency with the item view
    classes.

    The QHeaderView class is one of the \l{Model/View Classes} and is
    part of Qt's \l{Model/View Programming}{model/view framework}.

    The header gets the data for each section from the model using
    the QAbstractItemModel::headerData() function. You can set the data
    by using QAbstractItemModel::setHeaderData().

    Each header has an orientation() and a number of sections, given by
    the count() function. A section refers to a part of the header - either
    a row or a column, depending on the orientation. 
    
    Sections can be moved and resized using moveSection() and resizeSection();
    they can also be hidden and shown with hideSection() and showSection().

    Each section of a header is described by a section ID, specified by
    its section(), and can be located at a particular visualIndex() in the
    header. A section can have a sort indicator set with
    setSortIndicator(); this indicates whether the items in the associated
    item view will be sorted in the order given by the section.

    For a horizontal header the section is equivalent to a column in the
    model, and for a vertical header the section is equivalent to a row
    in the model.

    \section1 Moving Header Sections

    A header can be fixed in place, or made movable with setMovable().
    It can be made clickable with setClickable(), and has resizing behavior
    in accordance with setResizeMode().

    A header emits sectionMoved() if the user moves a section,
    sectionResized() if the user resizes a section, and
    sectionClicked() and sectionHandleDoubleClicked() in response to
    mouse clicks. A header also emits sectionCountChanged() and
    sectionAutoResize().

    You can identify a section using the logicalIndex() and logicalIndexAt()
    functions, or by its index position, using the visualIndex() and visualIndexAt()
    functions. The visual index will change if a section is moved, but the logical
    index will not change.

    \section1 Appearance

    QTableWidget and QTableView create default headers. If you want
    the headers to be visible, you can use \l{QFrame::}{setVisible()}.

    \note Each header renders the data for each section itself, and does not
    rely on a delegate. As a result, calling a header's setItemDelegate()
    function will have no effect.

    \sa {Model/View Programming}, QListView, QTableView, QTreeView
*/

/*!
    \enum QHeaderView::ResizeMode

    The resize mode specifies the behavior of the header sections.
    It can be set on the entire header view or on individual sections using setResizeMode().

    \value Interactive The user can resize the section.
                                The section can also be resized programmatically using resizeSection().
                                The section size defaults to \l defaultSectionSize.
                                (See also \l cascadingSectionResizes.)

    \value Fixed The user cannot resize the section.
                         The section can only be resized programmatically using resizeSection().
                         The section size defaults to \l defaultSectionSize.

    \value Stretch QHeaderView will automatically resize the section to fill the available space.
                           The size cannot be changed by the user or programmatically.

    \value ResizeToContents QHeaderView will automatically resize the section to its optimal
                                             size based on the contents of the entire column or row.
                                             The size cannot be changed by the user or programmatically.
					     (This value was introduced in 4.2)

    The following values are obsolete:
    \value Custom Use Fixed instead.

    \sa setResizeMode() stretchLastSection minimumSectionSize
*/

/*!
    \fn void QHeaderView::sectionMoved(int logicalIndex, int oldVisualIndex, int newVisualIndex)

    This signal is emitted when a section is moved. The section's logical
    index is specified by \a logicalIndex, the old index by \a oldVisualIndex,
    and the new index position by \a newVisualIndex.

    \sa moveSection()
*/

/*!
    \fn void QHeaderView::sectionResized(int logicalIndex, int oldSize, int newSize)

    This signal is emitted when a section is resized. The section's logical
    number is specified by \a logicalIndex, the old size by \a oldSize, and the
    new size by \a newSize.

    \sa resizeSection()
*/

/*!
    \fn void QHeaderView::sectionPressed(int logicalIndex)

    This signal is emitted when a section is pressed. The section's logical
    index is specified by \a logicalIndex.

    \sa setClickable()
*/

/*!
    \fn void QHeaderView::sectionClicked(int logicalIndex)

    This signal is emitted when a section is clicked. The section's logical
    index is specified by \a logicalIndex.

    Note that the sectionPressed signal will also be emitted.

    \sa setClickable(), sectionPressed()
*/

/*!
    \fn void QHeaderView::sectionEntered(int logicalIndex)
    \since 4.3

    This signal is emitted when the cursor moves over the section and the
    left mouse button is pressed. The section's logical index is specified
    by \a logicalIndex.

    \sa setClickable(), sectionPressed()
*/

/*!
    \fn void QHeaderView::sectionDoubleClicked(int logicalIndex)

    This signal is emitted when a section is double-clicked. The
    section's logical index is specified by \a logicalIndex.

    \sa setClickable()
*/

/*!
    \fn void QHeaderView::sectionCountChanged(int oldCount, int newCount)

    This signal is emitted when the number of sections changes; i.e.
    when sections are added or deleted. The original count is specified by
    \a oldCount, and the new count by \a newCount.

    \sa count(), length(), headerDataChanged()
*/

/*!
    \fn void QHeaderView::sectionHandleDoubleClicked(int logicalIndex)

    This signal is emitted when a section is double-clicked. The
    section's logical index is specified by \a logicalIndex.

    \sa setClickable()
*/

/*!
    \fn void QHeaderView::sortIndicatorChanged(int logicalIndex, Qt::SortOrder order)
    \since 4.3

    This signal is emitted when the section containing the sort indicator
    or the order indicated is changed. The section's logical index is
    specified by \a logicalIndex and the sort order is specified by \a order.

    \sa setSortIndicator()
*/

/*!
    \fn void QHeaderView::sectionAutoResize(int logicalIndex, QHeaderView::ResizeMode mode)

    This signal is emitted when a section is automatically resized.
    The section's logical index is specified by \a logicalIndex, and the
    resize mode by \a mode.

    \sa setResizeMode(), stretchLastSection()
*/
// ### Qt 5: change to sectionAutoResized()

/*!
  \fn void QHeaderView::geometriesChanged()
  \since 4.2

  This signal is emitted when the header geometries has changed.
*/

/*!
    \property QHeaderView::highlightSections
    \brief whether the sections containing selected items are highlighted
*/

/*!
    Creates a new generic header with the given \a orientation and \a parent.
*/
QHeaderView::QHeaderView(Qt::Orientation orientation, QWidget *parent)
    : QAbstractItemView(*new QHeaderViewPrivate, parent)
{
    Q_D(QHeaderView);
    d->setDefaultValues(orientation);
    initialize();
}

/*!
  \internal
*/
QHeaderView::QHeaderView(QHeaderViewPrivate &dd,
                         Qt::Orientation orientation, QWidget *parent)
    : QAbstractItemView(dd, parent)
{
    Q_D(QHeaderView);
    d->setDefaultValues(orientation);
    initialize();
}

/*!
  Destroys the header.
*/

QHeaderView::~QHeaderView()
{
}

/*!
  \internal
*/
void QHeaderView::initialize()
{
    Q_D(QHeaderView);
    setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
    setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
    setFrameStyle(NoFrame);
    setFocusPolicy(Qt::NoFocus);
    d->viewport->setMouseTracking(true);
    d->viewport->setBackgroundRole(QPalette::Button);
    d->textElideMode = Qt::ElideNone;
    delete d->itemDelegate;
}

/*!
  \reimp
*/
void QHeaderView::setModel(QAbstractItemModel *model)
{
    if (model == this->model())
        return;
    Q_D(QHeaderView);
    if (d->model && d->model != QAbstractItemModelPrivate::staticEmptyModel()) {
        if (d->orientation == Qt::Horizontal) {
            QObject::disconnect(d->model, SIGNAL(columnsInserted(QModelIndex,int,int)),
                                this, SLOT(sectionsInserted(QModelIndex,int,int)));
            QObject::disconnect(d->model, SIGNAL(columnsAboutToBeRemoved(QModelIndex,int,int)),
                                this, SLOT(sectionsAboutToBeRemoved(QModelIndex,int,int)));
            QObject::disconnect(d->model, SIGNAL(columnsRemoved(QModelIndex,int,int)),
                                this, SLOT(_q_sectionsRemoved(QModelIndex,int,int)));
        } else {
            QObject::disconnect(d->model, SIGNAL(rowsInserted(QModelIndex,int,int)),
                                this, SLOT(sectionsInserted(QModelIndex,int,int)));
            QObject::disconnect(d->model, SIGNAL(rowsAboutToBeRemoved(QModelIndex,int,int)),
                                this, SLOT(sectionsAboutToBeRemoved(QModelIndex,int,int)));
            QObject::disconnect(d->model, SIGNAL(rowsRemoved(QModelIndex,int,int)),
                                this, SLOT(_q_sectionsRemoved(QModelIndex,int,int)));
        }
        QObject::disconnect(d->model, SIGNAL(headerDataChanged(Qt::Orientation,int,int)),
                                this, SLOT(headerDataChanged(Qt::Orientation,int,int)));
        QObject::disconnect(d->model, SIGNAL(layoutAboutToBeChanged()),
                            this, SLOT(_q_layoutAboutToBeChanged()));
    }

    if (model && model != QAbstractItemModelPrivate::staticEmptyModel()) {
        if (d->orientation == Qt::Horizontal) {
            QObject::connect(model, SIGNAL(columnsInserted(QModelIndex,int,int)),
                             this, SLOT(sectionsInserted(QModelIndex,int,int)));
            QObject::connect(model, SIGNAL(columnsAboutToBeRemoved(QModelIndex,int,int)),
                this, SLOT(sectionsAboutToBeRemoved(QModelIndex,int,int)));
            QObject::connect(model, SIGNAL(columnsRemoved(QModelIndex,int,int)),
                this, SLOT(_q_sectionsRemoved(QModelIndex,int,int)));
        } else {
            QObject::connect(model, SIGNAL(rowsInserted(QModelIndex,int,int)),
                             this, SLOT(sectionsInserted(QModelIndex,int,int)));
            QObject::connect(model, SIGNAL(rowsAboutToBeRemoved(QModelIndex,int,int)),
                             this, SLOT(sectionsAboutToBeRemoved(QModelIndex,int,int)));
            QObject::connect(model, SIGNAL(rowsRemoved(QModelIndex,int,int)),
                             this, SLOT(_q_sectionsRemoved(QModelIndex,int,int)));
        }
        QObject::connect(model, SIGNAL(headerDataChanged(Qt::Orientation,int,int)),
                         this, SLOT(headerDataChanged(Qt::Orientation,int,int)));
        QObject::connect(model, SIGNAL(layoutAboutToBeChanged()),
                         this, SLOT(_q_layoutAboutToBeChanged()));
    }

    d->state = QHeaderViewPrivate::NoClear;
    QAbstractItemView::setModel(model);
    d->state = QHeaderViewPrivate::NoState;

    // Users want to set sizes and modes before the widget is shown.
    // Thus, we have to initialize when the model is set,
    // and not lazily like we do in the other views.
    initializeSections();
}

/*!
  Returns the orientation of the header.

  \sa Qt::Orientation
*/

Qt::Orientation QHeaderView::orientation() const
{
    Q_D(const QHeaderView);
    return d->orientation;
}

/*!
    Returns the offset of the header: this is the header's left-most
    (or top-most for vertical headers) visible pixel.

    \sa setOffset()
*/

int QHeaderView::offset() const
{
    Q_D(const QHeaderView);
    return d->offset;
}