source: trunk/src/gui/itemviews/qproxymodel.cpp@ 1058

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#include "qproxymodel.h"

#ifndef QT_NO_PROXYMODEL
#include <private/qproxymodel_p.h>
#include <qsize.h>
#include <qstringlist.h>

QT_BEGIN_NAMESPACE

/*!
    \class QProxyModel
    \obsolete
    \brief The QProxyModel class provides support for processing data
    passed between another model and a view.

    \ingroup model-view

    If you want to do filtering and sorting, see QSortFilterProxyModel.

    Proxy models provide a standard model interface that can be used to
    manipulate the data retrieved through an underlying model. They can be used to
    perform operations such as sorting and filtering on the data obtained without
    changing the contents of the model.

    Just as with subclasses of QAbstractItemView, QProxyModel provides the setModel()
    function that is used to specify the model to be acted on by the proxy.
    Views can be connected to either the underlying model or the proxy model with
    \l QAbstractItemView::setModel().

    Since views rely on the information provided in model indexes to identify
    items of data from models, and to position these items in some visual
    representation, proxy models must create their own model indexes instead of
    supplying model indexes from their underlying models.

    \sa \link model-view-programming.html Model/View Programming\endlink QAbstractItemModel

*/

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

QProxyModel::QProxyModel(QObject *parent)
    : QAbstractItemModel(*new QProxyModelPrivate, parent)
{
    Q_D(QProxyModel);
    setModel(&d->empty);
}

/*!
    \internal
*/
QProxyModel::QProxyModel(QProxyModelPrivate &dd, QObject *parent)
    : QAbstractItemModel(dd, parent)
{
    Q_D(QProxyModel);
    setModel(&d->empty);
}

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

/*!
    Sets the given \a model to be processed by the proxy model.
*/
void QProxyModel::setModel(QAbstractItemModel *model)
{
    Q_D(QProxyModel);
    if (d->model && d->model != &d->empty)
        disconnectFromModel(d->model);
    if (model) {
        d->model = model;
        connectToModel(model);
    } else {
        d->model = &d->empty;
    }
}

/*!
    Returns the model that contains the data that is available through the
    proxy model.
*/
QAbstractItemModel *QProxyModel::model() const
{
    Q_D(const QProxyModel);
    return d->model;
}

/*!
    Returns the model index with the given \a row, \a column, and \a parent.

    \sa QAbstractItemModel::index()
*/
QModelIndex QProxyModel::index(int row, int column, const QModelIndex &parent) const
{
    Q_D(const QProxyModel);
    return setProxyModel(d->model->index(row, column, setSourceModel(parent)));
}

/*!
    Returns the model index that corresponds to the parent of the given \a child
    index.
*/
QModelIndex QProxyModel::parent(const QModelIndex &child) const
{
    Q_D(const QProxyModel);
    return setProxyModel(d->model->parent(setSourceModel(child)));
}

/*!
    Returns the number of rows for the given \a parent.

    \sa QAbstractItemModel::rowCount()
*/
int QProxyModel::rowCount(const QModelIndex &parent) const
{
    Q_D(const QProxyModel);
    return d->model->rowCount(setSourceModel(parent));
}

/*!
    Returns the number of columns for the given \a parent.

    \sa QAbstractItemModel::columnCount()
*/
int QProxyModel::columnCount(const QModelIndex &parent) const
{
    Q_D(const QProxyModel);
    return d->model->columnCount(setSourceModel(parent));
}

/*!
    Returns true if the item corresponding to the \a parent index has child
    items; otherwise returns false.

    \sa QAbstractItemModel::hasChildren()
*/
bool QProxyModel::hasChildren(const QModelIndex &parent) const
{
    Q_D(const QProxyModel);
    return d->model->hasChildren(setSourceModel(parent));
}

/*!
    Returns the data stored in the item with the given \a index under the
    specified \a role.
*/
QVariant QProxyModel::data(const QModelIndex &index, int role) const
{
    Q_D(const QProxyModel);
    return d->model->data(setSourceModel(index), role);
}

/*!
    Sets the \a role data for the item at \a index to \a value.
    Returns true if successful; otherwise returns false.

    The base class implementation returns false. This function and
    data() must be reimplemented for editable models.

    \sa data() itemData() QAbstractItemModel::setData()
*/
bool QProxyModel::setData(const QModelIndex &index, const QVariant &value, int role)
{
    Q_D(const QProxyModel);
    return d->model->setData(setSourceModel(index), value, role);
}

/*!
    Returns the data stored in the \a section of the header with specified
    \a orientation under the given \a role.
*/
QVariant QProxyModel::headerData(int section, Qt::Orientation orientation, int role) const
{
    Q_D(const QProxyModel);
    return d->model->headerData(section, orientation, role);
}

/*!
    Sets the \a role data in the \a section of the header with the specified
    \a orientation to the \a value given.

    \sa QAbstractItemModel::setHeaderData()
*/
bool QProxyModel::setHeaderData(int section, Qt::Orientation orientation,
                                const QVariant &value, int role)
{
    Q_D(const QProxyModel);
    return d->model->setHeaderData(section, orientation, value, role);
}

/*!
    Returns a list of MIME types that are supported by the model.
*/
QStringList QProxyModel::mimeTypes() const
{
    Q_D(const QProxyModel);
    return d->model->mimeTypes();
}

/*!
    Returns MIME data for the specified \a indexes in the model.
*/
QMimeData *QProxyModel::mimeData(const QModelIndexList &indexes) const
{
    Q_D(const QProxyModel);
    QModelIndexList lst;
    for (int i = 0; i < indexes.count(); ++i)
        lst.append(setSourceModel(indexes.at(i)));
    return d->model->mimeData(lst);
}

/*!
    Returns true if the model accepts the \a data dropped onto an attached
    view for the specified \a action; otherwise returns false.

    The \a parent, \a row, and \a column details can be used to control
    which MIME types are acceptable to different parts of a model when
    received via the drag and drop system.
*/
bool QProxyModel::dropMimeData(const QMimeData *data, Qt::DropAction action,
                               int row, int column, const QModelIndex &parent)
{
    Q_D(const QProxyModel);
    return d->model->dropMimeData(data, action, row, column, setSourceModel(parent));
}

/*!
    Returns the drop actions that are supported by the model; this is
    a combination of the individual actions defined in \l Qt::DropActions.

    The selection of drop actions provided by the model will influence the
    behavior of the component that started the drag and drop operation.

    \sa \link dnd.html Drag and Drop\endlink