source: trunk/src/gui/itemviews/qabstractproxymodel.cpp@ 1021

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#include "qabstractproxymodel.h"

#ifndef QT_NO_PROXYMODEL

#include "qitemselectionmodel.h"
#include <private/qabstractproxymodel_p.h>

QT_BEGIN_NAMESPACE

/*!
    \since 4.1
    \class QAbstractProxyModel
    \brief The QAbstractProxyModel class provides a base class for proxy item
    models that can do sorting, filtering or other data processing tasks.
    \ingroup model-view

    This class defines the standard interface that proxy models must use to be
    able to interoperate correctly with other model/view components. It is not
    supposed to be instantiated directly.

    All standard proxy models are derived from the QAbstractProxyModel class.
    If you need to create a new proxy model class, it is usually better to
    subclass an existing class that provides the closest behavior to the one
    you want to provide.

    Proxy models that filter or sort items of data from a source model should
    be created by using or subclassing QSortFilterProxyModel.

    To subclass QAbstractProxyModel, you need to implement mapFromSource() and
    mapToSource(). The mapSelectionFromSource() and mapSelectionToSource()
    functions only need to be reimplemented if you need a behavior different
    from the default behavior.

    \note If the source model is deleted or no source model is specified, the
    proxy model operates on a empty placeholder model.

    \sa QSortFilterProxyModel, QAbstractItemModel, {Model/View Programming}
*/

//detects the deletion of the source model
void QAbstractProxyModelPrivate::_q_sourceModelDestroyed()
{
    model = QAbstractItemModelPrivate::staticEmptyModel();
}

/*!
    Constructs a proxy model with the given \a parent.
*/

QAbstractProxyModel::QAbstractProxyModel(QObject *parent)
    :QAbstractItemModel(*new QAbstractProxyModelPrivate, parent)
{
    setSourceModel(QAbstractItemModelPrivate::staticEmptyModel());
}

/*!
    \internal
*/

QAbstractProxyModel::QAbstractProxyModel(QAbstractProxyModelPrivate &dd, QObject *parent)
    : QAbstractItemModel(dd, parent)
{
    setSourceModel(QAbstractItemModelPrivate::staticEmptyModel());
}

/*!
    Destroys the proxy model.
*/
QAbstractProxyModel::~QAbstractProxyModel()
{

}

/*!
    Sets the given \a sourceModel to be processed by the proxy model.
*/
void QAbstractProxyModel::setSourceModel(QAbstractItemModel *sourceModel)
{
    Q_D(QAbstractProxyModel);
    if (d->model)
        disconnect(d->model, SIGNAL(destroyed()), this, SLOT(_q_sourceModelDestroyed()));

    if (sourceModel) {
        d->model = sourceModel;
        connect(d->model, SIGNAL(destroyed()), this, SLOT(_q_sourceModelDestroyed()));
    } else {
        d->model = QAbstractItemModelPrivate::staticEmptyModel();
    }
    d->roleNames = d->model->roleNames();
}

/*!
    Returns the model that contains the data that is available through the proxy model.
*/
QAbstractItemModel *QAbstractProxyModel::sourceModel() const
{
    Q_D(const QAbstractProxyModel);
    if (d->model == QAbstractItemModelPrivate::staticEmptyModel())
        return 0;
    return d->model;
}

/*!
    \reimp
 */
bool QAbstractProxyModel::submit()
{
    Q_D(QAbstractProxyModel);
    return d->model->submit();
}

/*!
    \reimp
 */
void QAbstractProxyModel::revert()
{
    Q_D(QAbstractProxyModel);
    d->model->revert();
}


/*!
  \fn QModelIndex QAbstractProxyModel::mapToSource(const QModelIndex &proxyIndex) const

  Reimplement this function to return the model index in the source model that
  corresponds to the \a proxyIndex in the proxy model.

  \sa mapFromSource()
*/

/*!
  \fn QModelIndex QAbstractProxyModel::mapFromSource(const QModelIndex &sourceIndex) const

  Reimplement this function to return the model index in the proxy model that
  corresponds to the \a sourceIndex from the source model.

  \sa mapToSource()
*/