path: root/src/widgets/itemviews/qproxymodel.cpp

/****************************************************************************
**
** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the QtGui module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** No Commercial Usage
** This file contains pre-release code and may not be distributed.
** You may use this file in accordance with the terms and conditions
** contained in the Technology Preview License Agreement accompanying
** this package.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights.  These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
**
**
**
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/

#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
*/
Qt::DropActions QProxyModel::supportedDropActions() const
{
    Q_D(const QProxyModel);
    return d->model->supportedDropActions();
}

/*!
    Inserts \a count rows into the model, creating new items as children of
    the given \a parent. The new rows are inserted before the \a row
    specified. If the \a parent item has no children, a single column is
    created to contain the required number of rows.

    Returns true if the rows were successfully inserted; otherwise
    returns false.

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

/*!
    Inserts \a count columns into the model, creating new items as children of
    the given \a parent. The new columns are inserted before the \a column
    specified. If the \a parent item has no children, a single row is created
    to contain the required number of columns.

    Returns true if the columns were successfully inserted; otherwise
    returns false.

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

/*!
    Fetches more child items of the given \a parent. This function is used by views
    to tell the model that they can display more data than the model has provided.

    \sa QAbstractItemModel::fetchMore()
*/
void QProxyModel::fetchMore(const QModelIndex &parent)
{
    Q_D(const QProxyModel);
    d->model->fetchMore(parent);
}

/*!
    Returns the item flags for the given \a index.
*/
Qt::ItemFlags QProxyModel::flags(const QModelIndex &index) const
{
    Q_D(const QProxyModel);
    return d->model->flags(setSourceModel(index));
}

/*!
    Sorts the child items in the specified \a column according to the sort
    order defined by \a order.

    \sa QAbstractItemModel::sort()
*/
void QProxyModel::sort(int column, Qt::SortOrder order)
{
    Q_D(QProxyModel);
    d->model->sort(column, order);
}

/*!
    Returns a list of model indexes that each contain the given \a value for
    the \a role specified. The search begins at the \a start index and is
    performed according to the specified \a flags. The search continues until
    the number of matching data items equals \a hits, the last row is reached,
    or the search reaches \a start again, depending on whether \c MatchWrap is
    specified in \a flags.

    \sa QAbstractItemModel::match()
*/
QModelIndexList QProxyModel::match(const QModelIndex &start,
                                   int role, const QVariant &value,
                                   int hits, Qt::MatchFlags flags) const
{
    Q_D(const QProxyModel);
    return d->model->match(start, role, value, hits, flags);
}

/*!
    Returns the size of the item that corresponds to the specified \a index.
*/
QSize QProxyModel::span(const QModelIndex &index) const
{
    Q_D(const QProxyModel);
    return d->model->span(setSourceModel(index));
}

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

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

/*!
    \internal
    Change the model pointer in the given \a source_index to point to the proxy model.
 */
QModelIndex QProxyModel::setProxyModel(const QModelIndex &source_index) const
{
    QModelIndex proxy_index = source_index;
    if (proxy_index.isValid())
        proxy_index.m = this;
    return proxy_index;
}

/*!
    \internal
    Change the model pointer in the given \a proxy_index to point to the source model.
 */
QModelIndex QProxyModel::setSourceModel(const QModelIndex &proxy_index) const
{
    Q_D(const QProxyModel);
    QModelIndex source_index = proxy_index;
    source_index.m = d->model;
    return source_index;
}

/*!
  \internal
  Connect to all the signals emitted by given \a model.
*/
void QProxyModel::connectToModel(const QAbstractItemModel *model) const
{
    connect(model, SIGNAL(dataChanged(QModelIndex,QModelIndex)),
            this, SLOT(_q_sourceDataChanged(QModelIndex,QModelIndex)));
    connect(model, SIGNAL(headerDataChanged(Qt::Orientation,int,int)),
            this, SIGNAL(headerDataChanged(Qt::Orientation,int,int))); // signal to signal
    connect(model, SIGNAL(rowsAboutToBeInserted(QModelIndex,int,int)),
            this, SLOT(_q_sourceRowsAboutToBeInserted(QModelIndex,int,int)));
    connect(model, SIGNAL(rowsInserted(QModelIndex,int,int)),
            this, SLOT(_q_sourceRowsInserted(QModelIndex,int,int)));
    connect(model, SIGNAL(rowsAboutToBeRemoved(QModelIndex,int,int)),
            this, SLOT(_q_sourceRowsAboutToBeRemoved(QModelIndex,int,int)));
    connect(model, SIGNAL(rowsRemoved(QModelIndex,int,int)),
            this, SLOT(_q_sourceRowsRemoved(QModelIndex,int,int)));
    connect(model, SIGNAL(columnsAboutToBeInserted(QModelIndex,int,int)),
            this, SLOT(_q_sourceColumnsAboutToBeInserted(QModelIndex,int,int)));
    connect(model, SIGNAL(columnsInserted(QModelIndex,int,int)),
            this, SLOT(_q_sourceColumnsInserted(QModelIndex,int,int)));
    connect(model, SIGNAL(columnsAboutToBeRemoved(QModelIndex,int,int)),
            this, SLOT(_q_sourceColumnsAboutToBeRemoved(QModelIndex,int,int)));
    connect(model, SIGNAL(columnsRemoved(QModelIndex,int,int)),
            this, SLOT(_q_sourceColumnsRemoved(QModelIndex,int,int)));
    connect(model, SIGNAL(modelReset()), this, SIGNAL(modelReset())); // signal to signal
    connect(model, SIGNAL(layoutAboutToBeChanged()), this, SIGNAL(layoutAboutToBeChanged())); // signal to signal
    connect(model, SIGNAL(layoutChanged()), this, SIGNAL(layoutChanged())); // signal to signal
}

/*!
  \internal
  Disconnect from all the signals emitted by the given \a model.
 */
void QProxyModel::disconnectFromModel(const QAbstractItemModel *model) const
{
    disconnect(model, SIGNAL(dataChanged(QModelIndex,QModelIndex)),
               this, SLOT(_q_sourceDataChanged(QModelIndex,QModelIndex)));
    disconnect(model, SIGNAL(headerDataChanged(Qt::Orientation,int,int)),
               this, SIGNAL(headerDataChanged(Qt::Orientation,int,int))); // signal to signal
    disconnect(model, SIGNAL(rowsAboutToBeInserted(QModelIndex,int,int)),
               this, SLOT(_q_sourceRowsAboutToBeInserted(QModelIndex,int,int)));
    disconnect(model, SIGNAL(rowsInserted(QModelIndex,int,int)),
               this, SLOT(rowsInserted(QModelIndex,int,int)));
    disconnect(model, SIGNAL(rowsAboutToBeRemoved(QModelIndex,int,int)),
               this, SLOT(_q_sourceRowsAboutToBeRemoved(QModelIndex,int,int)));
    disconnect(model, SIGNAL(rowsRemoved(QModelIndex,int,int)),
               this, SLOT(_q_sourceRowsRemoved(QModelIndex,int,int)));
    disconnect(model, SIGNAL(columnsAboutToBeInserted(QModelIndex,int,int)),
               this, SLOT(_q_sourceColumnsAboutToBeInserted(QModelIndex,int,int)));
    disconnect(model, SIGNAL(columnsInserted(QModelIndex,int,int)),
               this, SLOT(_q_sourceColumnsInserted(QModelIndex,int,int)));
    disconnect(model, SIGNAL(columnsAboutToBeRemoved(QModelIndex,int,int)),
               this, SLOT(_q_sourceColumnsAboutToBeRemoved(QModelIndex,int,int)));
    disconnect(model, SIGNAL(columnsRemoved(QModelIndex,int,int)),
               this, SLOT(_q_sourceColumnsRemoved(QModelIndex,int,int)));
    disconnect(model, SIGNAL(modelReset()), this, SIGNAL(modelReset())); // signal to signal
    disconnect(model, SIGNAL(layoutAboutToBeChanged()), this, SIGNAL(layoutAboutToBeChanged())); // signal to signal
    disconnect(model, SIGNAL(layoutChanged()), this, SIGNAL(layoutChanged())); // signal to signal
}

/*!
  \fn QObject *QProxyModel::parent() const
  \internal
*/

void QProxyModelPrivate::_q_sourceDataChanged(const QModelIndex &tl,const QModelIndex &br)
{
    Q_Q(QProxyModel);
    emit q->dataChanged(q->setProxyModel(tl), q->setProxyModel(br));
}

void QProxyModelPrivate::_q_sourceRowsAboutToBeInserted(const QModelIndex &parent, int first ,int last)
{
    Q_Q(QProxyModel);
    q->beginInsertRows(q->setProxyModel(parent), first, last);
}

void QProxyModelPrivate::_q_sourceRowsInserted(const QModelIndex &, int, int)
{
    Q_Q(QProxyModel);
    q->endInsertRows();
}

void QProxyModelPrivate::_q_sourceRowsAboutToBeRemoved(const QModelIndex &parent, int first, int last)
{
    Q_Q(QProxyModel);
    q->beginRemoveRows(q->setProxyModel(parent), first, last);
}

void QProxyModelPrivate::_q_sourceRowsRemoved(const QModelIndex &, int, int)
{
    Q_Q(QProxyModel);
    q->endRemoveRows();
}

void QProxyModelPrivate::_q_sourceColumnsAboutToBeInserted(const QModelIndex &parent, int first, int last)
{
    Q_Q(QProxyModel);
    q->beginInsertColumns(q->setProxyModel(parent), first, last);
}

void QProxyModelPrivate::_q_sourceColumnsInserted(const QModelIndex &, int, int)
{
    Q_Q(QProxyModel);
    q->endInsertColumns();
}

void QProxyModelPrivate::_q_sourceColumnsAboutToBeRemoved(const QModelIndex &parent, int first, int last)
{
    Q_Q(QProxyModel);
    q->beginRemoveColumns(q->setProxyModel(parent), first, last);
}


void QProxyModelPrivate::_q_sourceColumnsRemoved(const QModelIndex &, int, int)
{
    Q_Q(QProxyModel);
    q->endRemoveColumns();
}

QT_END_NAMESPACE

#include "moc_qproxymodel.cpp"

#endif // QT_NO_PROXYMODEL