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katie/src/core/kernel/qabstractitemmodel.cpp
Ivailo Monev a21a480105 copyright update 
Signed-off-by: Ivailo Monev <xakepa10@laimg.moc>
2019-07-02 18:13:44 +00:00

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/****************************************************************************
**
** Copyright (C) 2015 The Qt Company Ltd.
** Copyright (C) 2016-2019 Ivailo Monev
**
** This file is part of the QtCore module of the Katie Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** 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 or version 3 as published by the Free
** Software Foundation and appearing in the file LICENSE.LGPLv21 and
** LICENSE.LGPLv3 included in the packaging of this file. Please review the
** following information to ensure the GNU Lesser General Public License
** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** As a special exception, The Qt Company gives you certain additional
** rights. These rights are described in The Qt Company LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file. Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
** $QT_END_LICENSE$
**
****************************************************************************/
#include "qabstractitemmodel.h"
#include <qabstractitemmodel_p.h>
#include <qdatastream.h>
#include <qstringlist.h>
#include <qsize.h>
#include <qmimedata.h>
#include <qdebug.h>
#include <qvector.h>
#include <qstack.h>
#include <qbitarray.h>
#include <limits.h>
QT_BEGIN_NAMESPACE
QPersistentModelIndexData *QPersistentModelIndexData::create(const QModelIndex &index)
{
Q_ASSERT(index.isValid()); // we will _never_ insert an invalid index in the list
QPersistentModelIndexData *d = 0;
QAbstractItemModel *model = const_cast<QAbstractItemModel *>(index.model());
QHash<QModelIndex, QPersistentModelIndexData *> &indexes = model->d_func()->persistent.indexes;
const QHash<QModelIndex, QPersistentModelIndexData *>::iterator it = indexes.find(index);
if (it != indexes.end()) {
d = (*it);
} else {
d = new QPersistentModelIndexData(index);
indexes.insert(index, d);
}
Q_ASSERT(d);
return d;
}
void QPersistentModelIndexData::destroy(QPersistentModelIndexData *data)
{
Q_ASSERT(data);
Q_ASSERT(data->ref == 0);
QAbstractItemModel *model = const_cast<QAbstractItemModel *>(data->model);
// a valid persistent model index with a null model pointer can only happen if the model was destroyed
if (model) {
QAbstractItemModelPrivate *p = model->d_func();
Q_ASSERT(p);
p->removePersistentIndexData(data);
}
delete data;
}
/*!
\class QPersistentModelIndex
\brief The QPersistentModelIndex class is used to locate data in a data model.
\ingroup model-view
A QPersistentModelIndex is a model index that can be stored by an
application, and later used to access information in a model.
Unlike the QModelIndex class, it is safe to store a
QPersistentModelIndex since the model will ensure that references
to items will continue to be valid as long as they can be accessed
by the model.
It is good practice to check that persistent model indexes are valid
before using them.
\sa {Model/View Programming}, QModelIndex, QAbstractItemModel
*/
/*!
\fn QPersistentModelIndex::QPersistentModelIndex()
\internal
*/
QPersistentModelIndex::QPersistentModelIndex()
: d(0)
{
}
/*!
\fn QPersistentModelIndex::QPersistentModelIndex(const QPersistentModelIndex &other)
Creates a new QPersistentModelIndex that is a copy of the \a other persistent
model index.
*/
QPersistentModelIndex::QPersistentModelIndex(const QPersistentModelIndex &other)
: d(other.d)
{
if (d) d->ref.ref();
}
/*!
Creates a new QPersistentModelIndex that is a copy of the model \a index.
*/
QPersistentModelIndex::QPersistentModelIndex(const QModelIndex &index)
: d(0)
{
if (index.isValid()) {
d = QPersistentModelIndexData::create(index);
d->ref.ref();
}
}
/*!
\fn QPersistentModelIndex::~QPersistentModelIndex()
\internal
*/
QPersistentModelIndex::~QPersistentModelIndex()
{
if (d && !d->ref.deref()) {
QPersistentModelIndexData::destroy(d);
d = 0;
}
}
/*!
Returns true if this persistent model index is equal to the \a other
persistent model index; otherwise returns false.
All values in the persistent model index are used when comparing
with another persistent model index.
*/
bool QPersistentModelIndex::operator==(const QPersistentModelIndex &other) const
{
if (d && other.d)
return d->index == other.d->index;
return d == other.d;
}
/*!
\since 4.1
Returns true if this persistent model index is smaller than the \a other
persistent model index; otherwise returns false.
All values in the persistent model index are used when comparing
with another persistent model index.
*/
bool QPersistentModelIndex::operator<(const QPersistentModelIndex &other) const
{
if (d && other.d)
return d->index < other.d->index;
return d < other.d;
}
/*!
\fn bool QPersistentModelIndex::operator!=(const QPersistentModelIndex &other) const
\since 4.2
Returns true if this persistent model index is not equal to the \a
other persistent model index; otherwise returns false.
*/
/*!
Sets the persistent model index to refer to the same item in a model
as the \a other persistent model index.
*/
QPersistentModelIndex &QPersistentModelIndex::operator=(const QPersistentModelIndex &other)
{
if (d == other.d)
return *this;
if (d && !d->ref.deref())
QPersistentModelIndexData::destroy(d);
d = other.d;
if (d) d->ref.ref();
return *this;
}
/*!
Sets the persistent model index to refer to the same item in a model
as the \a other model index.
*/
QPersistentModelIndex &QPersistentModelIndex::operator=(const QModelIndex &other)
{
if (d && !d->ref.deref())
QPersistentModelIndexData::destroy(d);
if (other.isValid()) {
d = QPersistentModelIndexData::create(other);
if (d) d->ref.ref();
} else {
d = 0;
}
return *this;
}
/*!
\fn QPersistentModelIndex::operator const QModelIndex&() const
Cast operator that returns a const QModelIndex&.
*/
QPersistentModelIndex::operator const QModelIndex&() const
{
static const QModelIndex invalid;
if (d)
return d->index;
return invalid;
}
/*!
\fn bool QPersistentModelIndex::operator==(const QModelIndex &other) const
Returns true if this persistent model index refers to the same location as
the \a other model index; otherwise returns false.
All values in the persistent model index are used when comparing with
another model index.
*/
bool QPersistentModelIndex::operator==(const QModelIndex &other) const
{
if (d)
return d->index == other;
return !other.isValid();
}
/*!
\fn bool QPersistentModelIndex::operator!=(const QModelIndex &other) const
Returns true if this persistent model index does not refer to the same
location as the \a other model index; otherwise returns false.
*/
bool QPersistentModelIndex::operator!=(const QModelIndex &other) const
{
if (d)
return d->index != other;
return other.isValid();
}
/*!
\fn int QPersistentModelIndex::row() const
Returns the row this persistent model index refers to.
*/
int QPersistentModelIndex::row() const
{
if (d)
return d->index.row();
return -1;
}
/*!
\fn int QPersistentModelIndex::column() const
Returns the column this persistent model index refers to.
*/
int QPersistentModelIndex::column() const
{
if (d)
return d->index.column();
return -1;
}
/*!
\fn void *QPersistentModelIndex::internalPointer() const
\internal
Returns a \c{void} \c{*} pointer used by the model to associate the index with
the internal data structure.
*/
void *QPersistentModelIndex::internalPointer() const
{
if (d)
return d->index.internalPointer();
return 0;
}
/*!
\fn void *QPersistentModelIndex::internalId() const
\internal
Returns a \c{qint64} used by the model to associate the index with
the internal data structure.
*/
qint64 QPersistentModelIndex::internalId() const
{
if (d)
return d->index.internalId();
return 0;
}
/*!
Returns the parent QModelIndex for this persistent index, or an invalid
QModelIndex if it has no parent.
\sa child() sibling() model()
*/
QModelIndex QPersistentModelIndex::parent() const
{
if (d)
return d->index.parent();
return QModelIndex();
}
/*!
Returns the sibling at \a row and \a column or an invalid QModelIndex if
there is no sibling at this position.
\sa parent() child()
*/
QModelIndex QPersistentModelIndex::sibling(int row, int column) const
{
if (d)
return d->index.sibling(row, column);
return QModelIndex();
}
/*!
Returns the child of the model index that is stored in the given \a row
and \a column.
\sa parent() sibling()
*/
QModelIndex QPersistentModelIndex::child(int row, int column) const
{
if (d)
return d->index.child(row, column);
return QModelIndex();
}
/*!
Returns the data for the given \a role for the item referred to by the
index.
\sa Qt::ItemDataRole, QAbstractItemModel::setData()
*/
QVariant QPersistentModelIndex::data(int role) const
{
if (d)
return d->index.data(role);
return QVariant();
}
/*!
\since 4.2
Returns the flags for the item referred to by the index.
*/
Qt::ItemFlags QPersistentModelIndex::flags() const
{
if (d)
return d->index.flags();
return 0;
}
/*!
Returns the model that the index belongs to.
*/
const QAbstractItemModel *QPersistentModelIndex::model() const
{
if (d)
return d->index.model();
return 0;
}
/*!
\fn bool QPersistentModelIndex::isValid() const
Returns true if this persistent model index is valid; otherwise returns
false.
A valid index belongs to a model, and has non-negative row and column
numbers.
\sa model(), row(), column()
*/
bool QPersistentModelIndex::isValid() const
{
return d && d->index.isValid();
}
#ifndef QT_NO_DEBUG_STREAM
QDebug operator<<(QDebug dbg, const QModelIndex &idx)
{
#ifndef Q_BROKEN_DEBUG_STREAM
dbg.nospace() << "QModelIndex(" << idx.row() << ',' << idx.column()
<< ',' << idx.internalPointer() << ',' << idx.model() << ')';
return dbg.space();
#else
qWarning("This compiler doesn't support streaming QModelIndex to QDebug");
return dbg;
Q_UNUSED(idx);
#endif
}
QDebug operator<<(QDebug dbg, const QPersistentModelIndex &idx)
{
if (idx.d)
dbg << idx.d->index;
else
dbg << QModelIndex();
return dbg;
}
#endif
class QEmptyItemModel : public QAbstractItemModel
{
public:
explicit QEmptyItemModel(QObject *parent = Q_NULLPTR) : QAbstractItemModel(parent) {}
QModelIndex index(int, int, const QModelIndex &) const { return QModelIndex(); }
QModelIndex parent(const QModelIndex &) const { return QModelIndex(); }
int rowCount(const QModelIndex &) const { return 0; }
int columnCount(const QModelIndex &) const { return 0; }
bool hasChildren(const QModelIndex &) const { return false; }
QVariant data(const QModelIndex &, int) const { return QVariant(); }
};
Q_GLOBAL_STATIC(QEmptyItemModel, qEmptyModel)
QAbstractItemModel *QAbstractItemModelPrivate::staticEmptyModel()
{
return qEmptyModel();
}
struct DefaultRoleNames : public QHash<int, QByteArray>
{
DefaultRoleNames() {
(*this)[Qt::DisplayRole] = "display";
(*this)[Qt::DecorationRole] = "decoration";
(*this)[Qt::EditRole] = "edit";
(*this)[Qt::ToolTipRole] = "toolTip";
(*this)[Qt::StatusTipRole] = "statusTip";
(*this)[Qt::WhatsThisRole] = "whatsThis";
}
};
Q_GLOBAL_STATIC(DefaultRoleNames, qDefaultRoleNames)
const QHash<int,QByteArray> &QAbstractItemModelPrivate::defaultRoleNames()
{
return *qDefaultRoleNames();
}
static uint typeOfVariant(const QVariant &value)
{
//return 0 for integer, 1 for floating point and 2 for other
switch (value.userType()) {
case QVariant::Bool:
case QVariant::Int:
case QVariant::UInt:
case QVariant::LongLong:
case QVariant::ULongLong:
case QVariant::Char:
case QMetaType::Short:
case QMetaType::UShort:
case QMetaType::UChar:
case QMetaType::ULong:
case QMetaType::Long:
return 0;
case QVariant::Double:
case QVariant::Float:
return 1;
default:
return 2;
}
}
/*!
\internal
return true if \a value contains a numerical type
This function is used by our Q{Tree,Widget,Table}WidgetModel classes to sort.
*/
bool QAbstractItemModelPrivate::variantLessThan(const QVariant &v1, const QVariant &v2)
{
switch(qMax(typeOfVariant(v1), typeOfVariant(v2)))
{
case 0: //integer type
return v1.toLongLong() < v2.toLongLong();
case 1: //floating point
return v1.toReal() < v2.toReal();
default:
return v1.toString().localeAwareCompare(v2.toString()) < 0;
}
}
void QAbstractItemModelPrivate::removePersistentIndexData(QPersistentModelIndexData *data)
{
if (data->index.isValid()) {
int removed = persistent.indexes.remove(data->index);
Q_ASSERT_X(removed == 1, "QPersistentModelIndex::~QPersistentModelIndex",
"persistent model indexes corrupted"); //maybe the index was somewhat invalid?
// This assert may happen if the model use changePersistentIndex in a way that could result on two
// QPersistentModelIndex pointing to the same index.
Q_UNUSED(removed);
}
// make sure our optimization still works
for (int i = persistent.moved.count() - 1; i >= 0; --i) {
int idx = persistent.moved[i].indexOf(data);
if (idx >= 0)
persistent.moved[i].remove(idx);
}
// update the references to invalidated persistent indexes
for (int i = persistent.invalidated.count() - 1; i >= 0; --i) {
int idx = persistent.invalidated[i].indexOf(data);
if (idx >= 0)
persistent.invalidated[i].remove(idx);
}
}
void QAbstractItemModelPrivate::rowsAboutToBeInserted(const QModelIndex &parent,
int first, int last)
{
Q_Q(QAbstractItemModel);
Q_UNUSED(last);
QVector<QPersistentModelIndexData *> persistent_moved;
if (first < q->rowCount(parent)) {
for (QHash<QModelIndex, QPersistentModelIndexData *>::const_iterator it = persistent.indexes.constBegin();
it != persistent.indexes.constEnd(); ++it) {
QPersistentModelIndexData *data = *it;
const QModelIndex &index = data->index;
if (index.row() >= first && index.isValid() && index.parent() == parent) {
persistent_moved.append(data);
}
}
}
persistent.moved.push(persistent_moved);
}
void QAbstractItemModelPrivate::rowsInserted(const QModelIndex &parent,
int first, int last)
{
QVector<QPersistentModelIndexData *> persistent_moved = persistent.moved.pop();
int count = (last - first) + 1; // it is important to only use the delta, because the change could be nested
for (QVector<QPersistentModelIndexData *>::const_iterator it = persistent_moved.constBegin();
it != persistent_moved.constEnd(); ++it) {
QPersistentModelIndexData *data = *it;
QModelIndex old = data->index;
persistent.indexes.erase(persistent.indexes.find(old));
data->index = q_func()->index(old.row() + count, old.column(), parent);
if (data->index.isValid()) {
persistent.insertMultiAtEnd(data->index, data);
} else {
qWarning() << "QAbstractItemModel::endInsertRows: Invalid index (" << old.row() + count << ',' << old.column() << ") in model" << q_func();
}
}
}
void QAbstractItemModelPrivate::itemsAboutToBeMoved(const QModelIndex &srcParent, int srcFirst, int srcLast, const QModelIndex &destinationParent, int destinationChild, Qt::Orientation orientation)
{
QVector<QPersistentModelIndexData *> persistent_moved_explicitly;
QVector<QPersistentModelIndexData *> persistent_moved_in_source;
QVector<QPersistentModelIndexData *> persistent_moved_in_destination;
QHash<QModelIndex, QPersistentModelIndexData *>::const_iterator it;
const QHash<QModelIndex, QPersistentModelIndexData *>::const_iterator begin = persistent.indexes.constBegin();
const QHash<QModelIndex, QPersistentModelIndexData *>::const_iterator end = persistent.indexes.constEnd();
const bool sameParent = (srcParent == destinationParent);
const bool movingUp = (srcFirst > destinationChild);
for ( it = begin; it != end; ++it) {
QPersistentModelIndexData *data = *it;
const QModelIndex &index = data->index;
const QModelIndex &parent = index.parent();
const bool isSourceIndex = (parent == srcParent);
const bool isDestinationIndex = (parent == destinationParent);
int childPosition;
if (orientation == Qt::Vertical)
childPosition = index.row();
else
childPosition = index.column();
if (!index.isValid() || !(isSourceIndex || isDestinationIndex ) )
continue;
if (!sameParent && isDestinationIndex) {
if (childPosition >= destinationChild)
persistent_moved_in_destination.append(data);
continue;
}
if (sameParent && movingUp && childPosition < destinationChild)
continue;
if (sameParent && !movingUp && childPosition < srcFirst )
continue;
if (!sameParent && childPosition < srcFirst)
continue;
if (sameParent && (childPosition > srcLast) && (childPosition >= destinationChild ))
continue;
if ((childPosition <= srcLast) && (childPosition >= srcFirst)) {
persistent_moved_explicitly.append(data);
} else {
persistent_moved_in_source.append(data);
}
}
persistent.moved.push(persistent_moved_explicitly);
persistent.moved.push(persistent_moved_in_source);
persistent.moved.push(persistent_moved_in_destination);
}
/*!
\internal
Moves persistent indexes \a indexes by amount \a change. The change will be either a change in row value or a change in
column value depending on the value of \a orientation. The indexes may also be moved to a different parent if \a parent
differs from the existing parent for the index.
*/
void QAbstractItemModelPrivate::movePersistentIndexes(const QVector<QPersistentModelIndexData *> &indexes, int change, const QModelIndex &parent, Qt::Orientation orientation)
{
QVector<QPersistentModelIndexData *>::const_iterator it;
const QVector<QPersistentModelIndexData *>::const_iterator begin = indexes.constBegin();
const QVector<QPersistentModelIndexData *>::const_iterator end = indexes.constEnd();
for (it = begin; it != end; ++it)
{
QPersistentModelIndexData *data = *it;
int row = data->index.row();
int column = data->index.column();
if (Qt::Vertical == orientation)
row += change;
else
column += change;
persistent.indexes.erase(persistent.indexes.find(data->index));
data->index = q_func()->index(row, column, parent);
if (data->index.isValid()) {
persistent.insertMultiAtEnd(data->index, data);
} else {
qWarning() << "QAbstractItemModel::endMoveRows: Invalid index (" << row << "," << column << ") in model" << q_func();
}
}
}
void QAbstractItemModelPrivate::itemsMoved(const QModelIndex &sourceParent, int sourceFirst, int sourceLast, const QModelIndex &destinationParent, int destinationChild, Qt::Orientation orientation)
{
QVector<QPersistentModelIndexData *> moved_in_destination = persistent.moved.pop();
QVector<QPersistentModelIndexData *> moved_in_source = persistent.moved.pop();
QVector<QPersistentModelIndexData *> moved_explicitly = persistent.moved.pop();
const bool sameParent = (sourceParent == destinationParent);
const bool movingUp = (sourceFirst > destinationChild);
const int explicit_change = (!sameParent || movingUp) ? destinationChild - sourceFirst : destinationChild - sourceLast - 1 ;
const int source_change = (!sameParent || !movingUp) ? -1*(sourceLast - sourceFirst + 1) : sourceLast - sourceFirst + 1 ;
const int destination_change = sourceLast - sourceFirst + 1;
movePersistentIndexes(moved_explicitly, explicit_change, destinationParent, orientation);
movePersistentIndexes(moved_in_source, source_change, sourceParent, orientation);
movePersistentIndexes(moved_in_destination, destination_change, destinationParent, orientation);
}
void QAbstractItemModelPrivate::rowsAboutToBeRemoved(const QModelIndex &parent,
int first, int last)
{
QVector<QPersistentModelIndexData *> persistent_moved;
QVector<QPersistentModelIndexData *> persistent_invalidated;
// find the persistent indexes that are affected by the change, either by being in the removed subtree
// or by being on the same level and below the removed rows
for (QHash<QModelIndex, QPersistentModelIndexData *>::const_iterator it = persistent.indexes.constBegin();
it != persistent.indexes.constEnd(); ++it) {
QPersistentModelIndexData *data = *it;
bool level_changed = false;
QModelIndex current = data->index;
while (current.isValid()) {
QModelIndex current_parent = current.parent();
if (current_parent == parent) { // on the same level as the change
if (!level_changed && current.row() > last) // below the removed rows
persistent_moved.append(data);
else if (current.row() <= last && current.row() >= first) // in the removed subtree
persistent_invalidated.append(data);
break;
}
current = current_parent;
level_changed = true;
}
}
persistent.moved.push(persistent_moved);
persistent.invalidated.push(persistent_invalidated);
}
void QAbstractItemModelPrivate::rowsRemoved(const QModelIndex &parent,
int first, int last)
{
QVector<QPersistentModelIndexData *> persistent_moved = persistent.moved.pop();
int count = (last - first) + 1; // it is important to only use the delta, because the change could be nested
for (QVector<QPersistentModelIndexData *>::const_iterator it = persistent_moved.constBegin();
it != persistent_moved.constEnd(); ++it) {
QPersistentModelIndexData *data = *it;
QModelIndex old = data->index;
persistent.indexes.erase(persistent.indexes.find(old));
data->index = q_func()->index(old.row() - count, old.column(), parent);
if (data->index.isValid()) {
persistent.insertMultiAtEnd(data->index, data);
} else {
qWarning() << "QAbstractItemModel::endRemoveRows: Invalid index (" << old.row() - count << ',' << old.column() << ") in model" << q_func();
}
}
QVector<QPersistentModelIndexData *> persistent_invalidated = persistent.invalidated.pop();
for (QVector<QPersistentModelIndexData *>::const_iterator it = persistent_invalidated.constBegin();
it != persistent_invalidated.constEnd(); ++it) {
QPersistentModelIndexData *data = *it;
persistent.indexes.erase(persistent.indexes.find(data->index));
data->index = QModelIndex();
data->model = 0;
}
}
void QAbstractItemModelPrivate::columnsAboutToBeInserted(const QModelIndex &parent,
int first, int last)
{
Q_Q(QAbstractItemModel);
Q_UNUSED(last);
QVector<QPersistentModelIndexData *> persistent_moved;
if (first < q->columnCount(parent)) {
for (QHash<QModelIndex, QPersistentModelIndexData *>::const_iterator it = persistent.indexes.constBegin();
it != persistent.indexes.constEnd(); ++it) {
QPersistentModelIndexData *data = *it;
const QModelIndex &index = data->index;
if (index.column() >= first && index.isValid() && index.parent() == parent)
persistent_moved.append(data);
}
}
persistent.moved.push(persistent_moved);
}
void QAbstractItemModelPrivate::columnsInserted(const QModelIndex &parent,
int first, int last)
{
QVector<QPersistentModelIndexData *> persistent_moved = persistent.moved.pop();
int count = (last - first) + 1; // it is important to only use the delta, because the change could be nested
for (QVector<QPersistentModelIndexData *>::const_iterator it = persistent_moved.constBegin();
it != persistent_moved.constEnd(); ++it) {
QPersistentModelIndexData *data = *it;
QModelIndex old = data->index;
persistent.indexes.erase(persistent.indexes.find(old));
data->index = q_func()->index(old.row(), old.column() + count, parent);
if (data->index.isValid()) {
persistent.insertMultiAtEnd(data->index, data);
} else {
qWarning() << "QAbstractItemModel::endInsertColumns: Invalid index (" << old.row() << ',' << old.column() + count << ") in model" << q_func();
}
}
}
void QAbstractItemModelPrivate::columnsAboutToBeRemoved(const QModelIndex &parent,
int first, int last)
{
QVector<QPersistentModelIndexData *> persistent_moved;
QVector<QPersistentModelIndexData *> persistent_invalidated;
// find the persistent indexes that are affected by the change, either by being in the removed subtree
// or by being on the same level and to the right of the removed columns
for (QHash<QModelIndex, QPersistentModelIndexData *>::const_iterator it = persistent.indexes.constBegin();
it != persistent.indexes.constEnd(); ++it) {
QPersistentModelIndexData *data = *it;
bool level_changed = false;
QModelIndex current = data->index;
while (current.isValid()) {
QModelIndex current_parent = current.parent();
if (current_parent == parent) { // on the same level as the change
if (!level_changed && current.column() > last) // right of the removed columns
persistent_moved.append(data);
else if (current.column() <= last && current.column() >= first) // in the removed subtree
persistent_invalidated.append(data);
break;
}
current = current_parent;
level_changed = true;
}
}
persistent.moved.push(persistent_moved);
persistent.invalidated.push(persistent_invalidated);
}
void QAbstractItemModelPrivate::columnsRemoved(const QModelIndex &parent,
int first, int last)
{
QVector<QPersistentModelIndexData *> persistent_moved = persistent.moved.pop();
int count = (last - first) + 1; // it is important to only use the delta, because the change could be nested
for (QVector<QPersistentModelIndexData *>::const_iterator it = persistent_moved.constBegin();
it != persistent_moved.constEnd(); ++it) {
QPersistentModelIndexData *data = *it;
QModelIndex old = data->index;
persistent.indexes.erase(persistent.indexes.find(old));
data->index = q_func()->index(old.row(), old.column() - count, parent);
if (data->index.isValid()) {
persistent.insertMultiAtEnd(data->index, data);
} else {
qWarning() << "QAbstractItemModel::endRemoveColumns: Invalid index (" << old.row() << ',' << old.column() - count << ") in model" << q_func();
}
}
QVector<QPersistentModelIndexData *> persistent_invalidated = persistent.invalidated.pop();
for (QVector<QPersistentModelIndexData *>::const_iterator it = persistent_invalidated.constBegin();
it != persistent_invalidated.constEnd(); ++it) {
QPersistentModelIndexData *data = *it;
persistent.indexes.erase(persistent.indexes.find(data->index));
data->index = QModelIndex();
data->model = 0;
}
}
/*!
\class QModelIndex
\brief The QModelIndex class is used to locate data in a data model.
\ingroup model-view
This class is used as an index into item models derived from
QAbstractItemModel. The index is used by item views, delegates, and
selection models to locate an item in the model.
New QModelIndex objects are created by the model using the
QAbstractItemModel::createIndex() function. An \e invalid model index can
be constructed with the QModelIndex constructor. Invalid indexes are often
used as parent indexes when referring to top-level items in a model.
Model indexes refer to items in models, and contain all the information
required to specify their locations in those models. Each index is located
in a given row and column, and may have a parent index; use row(),
column(), and parent() to obtain this information. Each top-level item in a
model is represented by a model index that does not have a parent index -
in this case, parent() will return an invalid model index, equivalent to an
index constructed with the zero argument form of the QModelIndex()
constructor.
To obtain a model index that refers to an existing item in a model, call
QAbstractItemModel::index() with the required row and column values, and
the model index of the parent. When referring to top-level items in a
model, supply QModelIndex() as the parent index.
The model() function returns the model that the index references as a
QAbstractItemModel. The child() function is used to examine items held
under the index in the model. The sibling() function allows you to traverse
items in the model on the same level as the index.
\note Model indexes should be used immediately and then discarded. You
should not rely on indexes to remain valid after calling model functions
that change the structure of the model or delete items. If you need to
keep a model index over time use a QPersistentModelIndex.
\sa {Model/View Programming}, QPersistentModelIndex, QAbstractItemModel
*/
/*!
\fn QModelIndex::QModelIndex()
Creates a new empty model index. This type of model index is used to
indicate that the position in the model is invalid.
\sa isValid() QAbstractItemModel
*/
/*!
\fn QModelIndex::QModelIndex(int row, int column, void *data, const QAbstractItemModel *model)
\internal
Creates a new model index at the given \a row and \a column,
pointing to some \a data.
*/
/*!
\fn QModelIndex::QModelIndex(const QModelIndex &other)
Creates a new model index that is a copy of the \a other model
index.
*/
/*!
\fn QModelIndex::~QModelIndex()
Destroys the model index.
*/
/*!
\fn int QModelIndex::row() const
Returns the row this model index refers to.
*/
/*!
\fn int QModelIndex::column() const
Returns the column this model index refers to.
*/
/*!
\fn void *QModelIndex::internalPointer() const
Returns a \c{void} \c{*} pointer used by the model to associate
the index with the internal data structure.
\sa QAbstractItemModel::createIndex()
*/
/*!
\fn void *QModelIndex::internalId() const
Returns a \c{qint64} used by the model to associate
the index with the internal data structure.
\sa QAbstractItemModel::createIndex()
*/
/*!
\fn bool QModelIndex::isValid() const
Returns true if this model index is valid; otherwise returns false.
A valid index belongs to a model, and has non-negative row and column
numbers.
\sa model(), row(), column()
*/
/*!
\fn const QAbstractItemModel *QModelIndex::model() const
Returns a pointer to the model containing the item that this index
refers to.
A const pointer to the model is returned because calls to non-const
functions of the model might invalidate the model index and possibly
crash your application.
*/
/*!
\fn QModelIndex QModelIndex::sibling(int row, int column) const
Returns the sibling at \a row and \a column. If there is no sibling at this
position, an invalid QModelIndex is returned.
\sa parent(), child()
*/
/*!
\fn QModelIndex QModelIndex::child(int row, int column) const
Returns the child of the model index that is stored in the given \a row and
\a column.
\note This function does not work for an invalid model index which is often
used as the root index.
\sa parent(), sibling()
*/
/*!
\fn QVariant QModelIndex::data(int role) const
Returns the data for the given \a role for the item referred to by the
index.
*/
/*!
\fn Qt::ItemFlags QModelIndex::flags() const
\since 4.2
Returns the flags for the item referred to by the index.
*/
/*!
\fn bool QModelIndex::operator==(const QModelIndex &other) const
Returns true if this model index refers to the same location as the
\a other model index; otherwise returns false.
All values in the model index are used when comparing with another model
index.
*/
/*!
\fn bool QModelIndex::operator!=(const QModelIndex &other) const
Returns true if this model index does not refer to the same location as
the \a other model index; otherwise returns false.
*/
/*!
\fn QModelIndex QModelIndex::parent() const
Returns the parent of the model index, or QModelIndex() if it has no
parent.
\sa child(), sibling(), model()
*/
/*!
\class QAbstractItemModel
\brief The QAbstractItemModel class provides the abstract interface for
item model classes.
\ingroup model-view
The QAbstractItemModel class defines the standard interface that item
models must use to be able to interoperate with other components in the
model/view architecture. It is not supposed to be instantiated directly.
Instead, you should subclass it to create new models.
The QAbstractItemModel class is one of the \l{Model/View Classes}
and is part of Qt's \l{Model/View Programming}{model/view framework}.
If you need a model to use with a QListView or a QTableView, you should
consider subclassing QAbstractListModel or QAbstractTableModel instead of
this class.
The underlying data model is exposed to views and delegates as a hierarchy
of tables. If you do not make use of the hierarchy, then the model is a
simple table of rows and columns. Each item has a unique index specified by
a QModelIndex.
\image modelindex-no-parent.png
Every item of data that can be accessed via a model has an associated model
index. You can obtain this model index using the index() function. Each
index may have a sibling() index; child items have a parent() index.
Each item has a number of data elements associated with it and they can be
retrieved by specifying a role (see \l Qt::ItemDataRole) to the model's
data() function. Data for all available roles can be obtained at the same
time using the itemData() function.
Data for each role is set using a particular \l Qt::ItemDataRole. Data for
individual roles are set individually with setData(), or they can be set
for all roles with setItemData().
Items can be queried with flags() (see \l Qt::ItemFlag) to see if they can
be selected, dragged, or manipulated in other ways.
If an item has child objects, hasChildren() returns true for the
corresponding index.
The model has a rowCount() and a columnCount() for each level of the
hierarchy. Rows and columns can be inserted and removed with insertRows(),
insertColumns(), removeRows(), and removeColumns().
The model emits signals to indicate changes. For example, dataChanged() is
emitted whenever items of data made available by the model are changed.
Changes to the headers supplied by the model cause headerDataChanged() to
be emitted. If the structure of the underlying data changes, the model can
emit layoutChanged() to indicate to any attached views that they should
redisplay any items shown, taking the new structure into account.
The items available through the model can be searched for particular data
using the match() function.
To sort the model, you can use sort().
\section1 Subclassing
\note Some general guidelines for subclassing models are available in the
\l{Model Subclassing Reference}.
When subclassing QAbstractItemModel, at the very least you must implement
index(), parent(), rowCount(), columnCount(), and data(). These functions
are used in all read-only models, and form the basis of editable models.
You can also reimplement hasChildren() to provide special behavior for
models where the implementation of rowCount() is expensive. This makes it
possible for models to restrict the amount of data requested by views, and
can be used as a way to implement lazy population of model data.
To enable editing in your model, you must also implement setData(), and
reimplement flags() to ensure that \c ItemIsEditable is returned. You can
also reimplement headerData() and setHeaderData() to control the way the
headers for your model are presented.
The dataChanged() and headerDataChanged() signals must be emitted
explicitly when reimplementing the setData() and setHeaderData() functions,
respectively.
Custom models need to create model indexes for other components to use. To
do this, call createIndex() with suitable row and column numbers for the
item, and an identifier for it, either as a pointer or as an integer value.
The combination of these values must be unique for each item. Custom models
typically use these unique identifiers in other reimplemented functions to
retrieve item data and access information about the item's parents and
children. See the \l{Simple Tree Model Example} for more information about
unique identifiers.
It is not necessary to support every role defined in Qt::ItemDataRole.
Depending on the type of data contained within a model, it may only be
useful to implement the data() function to return valid information for
some of the more common roles. Most models provide at least a textual
representation of item data for the Qt::DisplayRole, and well-behaved
models should also provide valid information for the Qt::ToolTipRole and
Qt::WhatsThisRole. Supporting these roles enables models to be used with
standard Qt views. However, for some models that handle highly-specialized
data, it may be appropriate to provide data only for user-defined roles.
Models that provide interfaces to resizable data structures can provide
implementations of insertRows(), removeRows(), insertColumns(),and
removeColumns(). When implementing these functions, it is important to
notify any connected views about changes to the model's dimensions both
\e before and \e after they occur:
\list
\o An insertRows() implementation must call beginInsertRows() \e before
inserting new rows into the data structure, and endInsertRows()
\e{immediately afterwards}.
\o An insertColumns() implementation must call beginInsertColumns()
\e before inserting new columns into the data structure, and
endInsertColumns() \e{immediately afterwards}.
\o A removeRows() implementation must call beginRemoveRows() \e before
the rows are removed from the data structure, and endRemoveRows()
\e{immediately afterwards}.
\o A removeColumns() implementation must call beginRemoveColumns()
\e before the columns are removed from the data structure, and
endRemoveColumns() \e{immediately afterwards}.
\endlist
The \e private signals that these functions emit give attached components
the chance to take action before any data becomes unavailable. The
encapsulation of the insert and remove operations with these begin and end
functions also enables the model to manage \l{QPersistentModelIndex}
{persistent model indexes} correctly. \bold{If you want selections to be
handled properly, you must ensure that you call these functions.} If you
insert or remove an item with children, you do not need to call these
functions for the child items. In other words, the parent item will take
care of its child items.
To create models that populate incrementally, you can reimplement
fetchMore() and canFetchMore(). If the reimplementation of fetchMore() adds
rows to the model, \l{QAbstractItemModel::}{beginInsertRows()} and
\l{QAbstractItemModel::}{endInsertRows()} must be called.
\sa {Model Classes}, {Model Subclassing Reference}, QModelIndex,
QAbstractItemView, {Using drag and drop with item views},
{Simple DOM Model Example}, {Simple Tree Model Example},
{Editable Tree Model Example}, {Fetch More Example}
*/
/*!
\fn QModelIndex QAbstractItemModel::index(int row, int column, const QModelIndex &parent) const = 0
Returns the index of the item in the model specified by the given \a row,
\a column and \a parent index.
When reimplementing this function in a subclass, call createIndex() to
generate model indexes that other components can use to refer to items in
your model.
\sa createIndex()
*/
/*!
\fn bool QAbstractItemModel::insertColumn(int column, const QModelIndex &parent)
Inserts a single column before the given \a column in the child items of
the \a parent specified.
Returns true if the column is inserted; otherwise returns false.
\sa insertColumns() insertRow() removeColumn()
*/
/*!
\fn bool QAbstractItemModel::insertRow(int row, const QModelIndex &parent)
\note The base class implementation of this function does nothing and
returns false.
Inserts a single row before the given \a row in the child items of the
\a parent specified.
Returns true if the row is inserted; otherwise returns false.
\sa insertRows() insertColumn() removeRow()
*/
/*!
\fn QObject *QAbstractItemModel::parent() const
\internal
*/
/*!
\fn QModelIndex QAbstractItemModel::parent(const QModelIndex &index) const = 0
Returns the parent of the model item with the given \a index. If the item
has no parent, an invalid QModelIndex is returned.
A common convention used in models that expose tree data structures is that
only items in the first column have children. For that case, when
reimplementing this function in a subclass the column of the returned
QModelIndex would be 0.
When reimplementing this function in a subclass, be careful to avoid
calling QModelIndex member functions, such as QModelIndex::parent(), since
indexes belonging to your model will simply call your implementation,
leading to infinite recursion.
\sa createIndex()
*/
/*!
\fn bool QAbstractItemModel::removeColumn(int column, const QModelIndex &parent)
Removes the given \a column from the child items of the \a parent
specified.
Returns true if the column is removed; otherwise returns false.
\sa removeColumns(), removeRow(), insertColumn()
*/
/*!
\fn bool QAbstractItemModel::removeRow(int row, const QModelIndex &parent)
Removes the given \a row from the child items of the \a parent specified.
Returns true if the row is removed; otherwise returns false.
This is a convenience function that calls removeRows(). The
QAbstractItemModel implementation of removeRows() does nothing.
\sa removeRows(), removeColumn(), insertRow()
*/
/*!
\fn void QAbstractItemModel::headerDataChanged(Qt::Orientation orientation, int first, int last)
This signal is emitted whenever a header is changed. The \a orientation
indicates whether the horizontal or vertical header has changed. The
sections in the header from the \a first to the \a last need to be updated.
When reimplementing the setHeaderData() function, this signal must be
emitted explicitly.
If you are changing the number of columns or rows you do not need to emit
this signal, but use the begin/end functions (refer to the section on
subclassing in the QAbstractItemModel class description for details).
\sa headerData(), setHeaderData(), dataChanged()
*/
/*!
\fn void QAbstractItemModel::layoutAboutToBeChanged()
\since 4.2
This signal is emitted just before the layout of a model is changed.
Components connected to this signal use it to adapt to changes in the
model's layout.
Subclasses should update any persistent model indexes after emitting
layoutAboutToBeChanged().
\sa layoutChanged(), changePersistentIndex()
*/
/*!
\fn void QAbstractItemModel::layoutChanged()
This signal is emitted whenever the layout of items exposed by the model
has changed; for example, when the model has been sorted. When this signal
is received by a view, it should update the layout of items to reflect this
change.
When subclassing QAbstractItemModel or QAbstractProxyModel, ensure that you
emit layoutAboutToBeChanged() before changing the order of items or
altering the structure of the data you expose to views, and emit
layoutChanged() after changing the layout.
Subclasses should update any persistent model indexes before emitting
layoutChanged(). In other words, when the structure changes:
\list
\o emit layoutAboutToBeChanged
\o Remember the QModelIndex that will change
\o Update your internal data
\o Call changePersistentIndex()
\o emit layoutChanged
\endlist
\sa layoutAboutToBeChanged(), dataChanged(), headerDataChanged(), modelReset(),
changePersistentIndex()
*/
/*!
\since 4.8
This slot is called just after the internal data of a model is cleared
while it is being reset.
This slot is provided the convenience of subclasses of concrete proxy
models, such as subclasses of QSortFilterProxyModel which maintain extra
data.
\snippet doc/src/snippets/code/src_corelib_kernel_qabstractitemmodel.cpp 10
\sa modelAboutToBeReset(), modelReset()
*/
void QAbstractItemModel::resetInternalData()
{
}
/*!
Constructs an abstract item model with the given \a parent.
*/
QAbstractItemModel::QAbstractItemModel(QObject *parent)
: QObject(*new QAbstractItemModelPrivate, parent)
{
}
/*!
\internal
*/
QAbstractItemModel::QAbstractItemModel(QAbstractItemModelPrivate &dd, QObject *parent)
: QObject(dd, parent)
{
}
/*!
Destroys the abstract item model.
*/
QAbstractItemModel::~QAbstractItemModel()
{
d_func()->invalidatePersistentIndexes();
}
/*!
\fn QModelIndex QAbstractItemModel::sibling(int row, int column, const QModelIndex &index) const
Returns the sibling at \a row and \a column for the item at \a index, or an
invalid QModelIndex if there is no sibling at that location.
sibling() is just a convenience function that finds the item's parent, and
uses it to retrieve the index of the child item in the specified \a row and
\a column.
\sa index(), QModelIndex::row(), QModelIndex::column()
*/
/*!
\fn int QAbstractItemModel::rowCount(const QModelIndex &parent) const
Returns the number of rows under the given \a parent. When the parent is
valid it means that rowCount is returning the number of children of parent.
\note When implementing a table based model, rowCount() should return 0
when the parent is valid.
\sa columnCount()
*/
/*!
\fn int QAbstractItemModel::columnCount(const QModelIndex &parent) const
Returns the number of columns for the children of the given \a parent.
In most subclasses, the number of columns is independent of the \a parent.
For example:
\snippet examples/itemviews/simpledommodel/dommodel.cpp 2
\note When implementing a table based model, columnCount() should return 0
when the parent is valid.
\sa rowCount()
*/
/*!
\fn void QAbstractItemModel::dataChanged(const QModelIndex &topLeft, const QModelIndex &bottomRight)
This signal is emitted whenever the data in an existing item changes.
If the items are of the same parent, the affected ones are those between
\a topLeft and \a bottomRight inclusive. If the items do not have the same
parent, the behavior is undefined.
When reimplementing the setData() function, this signal must be emitted
explicitly.
\sa headerDataChanged(), setData(), layoutChanged()
*/
/*!
\fn void QAbstractItemModel::rowsInserted(const QModelIndex &parent, int start, int end)
This signal is emitted after rows have been inserted into the
model. The new items are those between \a start and \a end
inclusive, under the given \a parent item.
\note Components connected to this signal use it to adapt to changes in the
model's dimensions. It can only be emitted by the QAbstractItemModel
implementation, and cannot be explicitly emitted in subclass code.
\sa insertRows(), beginInsertRows()
*/
/*!
\fn void QAbstractItemModel::rowsAboutToBeInserted(const QModelIndex &parent, int start, int end)
This signal is emitted just before rows are inserted into the model. The
new items will be positioned between \a start and \a end inclusive, under
the given \a parent item.
\note Components connected to this signal use it to adapt to changes
in the model's dimensions. It can only be emitted by the QAbstractItemModel
implementation, and cannot be explicitly emitted in subclass code.
\sa insertRows(), beginInsertRows()
*/
/*!
\fn void QAbstractItemModel::rowsRemoved(const QModelIndex &parent, int start, int end)
This signal is emitted after rows have been removed from the model. The
removed items are those between \a start and \a end inclusive, under the
given \a parent item.
\note Components connected to this signal use it to adapt to changes
in the model's dimensions. It can only be emitted by the QAbstractItemModel
implementation, and cannot be explicitly emitted in subclass code.
\sa removeRows(), beginRemoveRows()
*/
/*!
\fn void QAbstractItemModel::rowsAboutToBeRemoved(const QModelIndex &parent, int start, int end)
This signal is emitted just before rows are removed from the model. The
items that will be removed are those between \a start and \a end inclusive,
under the given \a parent item.
\note Components connected to this signal use it to adapt to changes
in the model's dimensions. It can only be emitted by the QAbstractItemModel
implementation, and cannot be explicitly emitted in subclass code.
\sa removeRows(), beginRemoveRows()
*/
/*!
\fn void QAbstractItemModel::rowsMoved(const QModelIndex &sourceParent, int sourceStart, int sourceEnd, const QModelIndex &destinationParent, int destinationRow)
\since 4.6
This signal is emitted after rows have been moved within the
model. The items between \a sourceStart and \a sourceEnd
inclusive, under the given \a sourceParent item have been moved to \a destinationParent
starting at the row \a destinationRow.
\bold{Note:} Components connected to this signal use it to adapt to changes
in the model's dimensions. It can only be emitted by the QAbstractItemModel
implementation, and cannot be explicitly emitted in subclass code.
\sa beginMoveRows()
*/
/*!
\fn void QAbstractItemModel::rowsAboutToBeMoved(const QModelIndex &sourceParent, int sourceStart, int sourceEnd, const QModelIndex &destinationParent, int destinationRow)
\since 4.6
This signal is emitted just before rows are moved within the
model. The items that will be moved are those between \a sourceStart and \a sourceEnd
inclusive, under the given \a sourceParent item. They will be moved to \a destinationParent
starting at the row \a destinationRow.
\bold{Note:} Components connected to this signal use it to adapt to changes
in the model's dimensions. It can only be emitted by the QAbstractItemModel
implementation, and cannot be explicitly emitted in subclass code.
\sa beginMoveRows()
*/
/*!
\fn void QAbstractItemModel::columnsMoved(const QModelIndex &sourceParent, int sourceStart, int sourceEnd, const QModelIndex &destinationParent, int destinationColumn)
\since 4.6
This signal is emitted after columns have been moved within the
model. The items between \a sourceStart and \a sourceEnd
inclusive, under the given \a sourceParent item have been moved to \a destinationParent
starting at the column \a destinationColumn.
\bold{Note:} Components connected to this signal use it to adapt to changes
in the model's dimensions. It can only be emitted by the QAbstractItemModel
implementation, and cannot be explicitly emitted in subclass code.
\sa beginMoveRows()
*/
/*!
\fn void QAbstractItemModel::columnsAboutToBeMoved(const QModelIndex &sourceParent, int sourceStart, int sourceEnd, const QModelIndex &destinationParent, int destinationColumn)
\since 4.6
This signal is emitted just before columns are moved within the
model. The items that will be moved are those between \a sourceStart and \a sourceEnd
inclusive, under the given \a sourceParent item. They will be moved to \a destinationParent
starting at the column \a destinationColumn.
\bold{Note:} Components connected to this signal use it to adapt to changes
in the model's dimensions. It can only be emitted by the QAbstractItemModel
implementation, and cannot be explicitly emitted in subclass code.
\sa beginMoveRows()
*/
/*!
\fn void QAbstractItemModel::columnsInserted(const QModelIndex &parent, int start, int end)
This signal is emitted after columns have been inserted into the model. The
new items are those between \a start and \a end inclusive, under the given
\a parent item.
\note Components connected to this signal use it to adapt to changes in the
model's dimensions. It can only be emitted by the QAbstractItemModel
implementation, and cannot be explicitly emitted in subclass code.
\sa insertColumns(), beginInsertColumns()
*/
/*!
\fn void QAbstractItemModel::columnsAboutToBeInserted(const QModelIndex &parent, int start, int end)
This signal is emitted just before columns are inserted into the model. The
new items will be positioned between \a start and \a end inclusive, under
the given \a parent item.
\note Components connected to this signal use it to adapt to changes in the
model's dimensions. It can only be emitted by the QAbstractItemModel
implementation, and cannot be explicitly emitted in subclass code.
\sa insertColumns(), beginInsertColumns()
*/
/*!
\fn void QAbstractItemModel::columnsRemoved(const QModelIndex &parent, int start, int end)
This signal is emitted after columns have been removed from the model.
The removed items are those between \a start and \a end inclusive,
under the given \a parent item.
\note Components connected to this signal use it to adapt to changes in
the model's dimensions. It can only be emitted by the QAbstractItemModel
implementation, and cannot be explicitly emitted in subclass code.
\sa removeColumns(), beginRemoveColumns()
*/
/*!
\fn void QAbstractItemModel::columnsAboutToBeRemoved(const QModelIndex &parent, int start, int end)
This signal is emitted just before columns are removed from the model. The
items to be removed are those between \a start and \a end inclusive, under
the given \a parent item.
\note Components connected to this signal use it to adapt to changes in the
model's dimensions. It can only be emitted by the QAbstractItemModel
implementation, and cannot be explicitly emitted in subclass code.
\sa removeColumns(), beginRemoveColumns()
*/
/*!
Returns true if the model returns a valid QModelIndex for \a row and
\a column with \a parent, otherwise returns false.
*/
bool QAbstractItemModel::hasIndex(int row, int column, const QModelIndex &parent) const
{
if (row < 0 || column < 0)
return false;
return row < rowCount(parent) && column < columnCount(parent);
}
/*!
Returns true if \a parent has any children; otherwise returns false.
Use rowCount() on the parent to find out the number of children.
\sa parent() index()
*/
bool QAbstractItemModel::hasChildren(const QModelIndex &parent) const
{
return (rowCount(parent) > 0) && (columnCount(parent) > 0);
}
/*!
Returns a map with values for all predefined roles in the model for the
item at the given \a index.
Reimplement this function if you want to extend the default behavior of
this function to include custom roles in the map.
\sa Qt::ItemDataRole, data()
*/
QMap<int, QVariant> QAbstractItemModel::itemData(const QModelIndex &index) const
{
QMap<int, QVariant> roles;
for (int i = 0; i < Qt::UserRole; ++i) {
QVariant variantData = data(index, i);
if (variantData.isValid())
roles.insert(i, variantData);
}
return roles;
}
/*!
Sets the \a role data for the item at \a index to \a value.
Returns true if successful; otherwise returns false.
The dataChanged() signal should be emitted if the data was successfully
set.
The base class implementation returns false. This function and data() must
be reimplemented for editable models.
\sa Qt::ItemDataRole, data(), itemData()
*/
bool QAbstractItemModel::setData(const QModelIndex &index, const QVariant &value, int role)
{
Q_UNUSED(index);
Q_UNUSED(value);
Q_UNUSED(role);
return false;
}
/*!
\fn QVariant QAbstractItemModel::data(const QModelIndex &index, int role) const = 0
Returns the data stored under the given \a role for the item referred to
by the \a index.
\note If you do not have a value to return, return an \bold invalid
QVariant instead of returning 0.
\sa Qt::ItemDataRole, setData(), headerData()
*/
/*!
Sets the role data for the item at \a index to the associated value in
\a roles, for every Qt::ItemDataRole.
Returns true if successful; otherwise returns false.
Roles that are not in \a roles will not be modified.
\sa setData() data() itemData()
*/
bool QAbstractItemModel::setItemData(const QModelIndex &index, const QMap<int, QVariant> &roles)
{
bool b = true;
for (QMap<int, QVariant>::ConstIterator it = roles.begin(); it != roles.end(); ++it)
b = b && setData(index, it.value(), it.key());
return b;
}
/*!
Returns a list of MIME types that can be used to describe a list of model
indexes.
\sa mimeData()
*/
QStringList QAbstractItemModel::mimeTypes() const
{
QStringList types;
types << QLatin1String("application/x-qabstractitemmodeldatalist");
return types;
}
/*!
Returns an object that contains serialized items of data corresponding to
the list of \a indexes specified. The formats used to describe the encoded
data is obtained from the mimeTypes() function.
If the list of indexes is empty, or there are no supported MIME types, 0 is
returned rather than a serialized empty list.
\sa mimeTypes(), dropMimeData()
*/
QMimeData *QAbstractItemModel::mimeData(const QModelIndexList &indexes) const
{
if (indexes.count() <= 0)
return 0;
QStringList types = mimeTypes();
if (types.isEmpty())
return 0;
QMimeData *data = new QMimeData();
QString format = types.at(0);
QByteArray encoded;
QDataStream stream(&encoded, QIODevice::WriteOnly);
encodeData(indexes, stream);
data->setData(format, encoded);
return data;
}
/*!
Handles the \a data supplied by a drag and drop operation that ended with
the given \a action.
Returns true if the data and action can be handled by the model; otherwise
returns false.
The specified \a row, \a column and \a parent indicate the location of an
item in the model where the operation ended. It is the responsibility of
the model to complete the action at the correct location.
For instance, a drop action on an item in a QTreeView can result in new
items either being inserted as children of the item specified by \a row,
\a column, and \a parent, or as siblings of the item.
When \a row and \a column are -1 it means that the dropped data should be
considered as dropped directly on \a parent. Usually this will mean
appending the data as child items of \a parent. If \a row and column are
greater than or equal zero, it means that the drop occurred just before the
specified \a row and \a column in the specified \a parent.
\sa supportedDropActions(), {Using drag and drop with item views}
*/
bool QAbstractItemModel::dropMimeData(const QMimeData *data, Qt::DropAction action,
int row, int column, const QModelIndex &parent)
{
// check if the action is supported
if (!data || !(action == Qt::CopyAction || action == Qt::MoveAction))
return false;
// check if the format is supported
QStringList types = mimeTypes();
if (types.isEmpty())
return false;
QString format = types.at(0);
if (!data->hasFormat(format))
return false;
if (row > rowCount(parent))
row = rowCount(parent);
if (row == -1)
row = rowCount(parent);
if (column == -1)
column = 0;
// decode and insert
QByteArray encoded = data->data(format);
QDataStream stream(&encoded, QIODevice::ReadOnly);
return decodeData(row, column, parent, stream);
}
/*!
\since 4.2
Returns the drop actions supported by this model.
The default implementation returns Qt::CopyAction. Reimplement this
function if you wish to support additional actions. You must also
reimplement the dropMimeData() function to handle the additional
operations.
\sa dropMimeData(), Qt::DropActions, {Using drag and drop with item
views}
*/
Qt::DropActions QAbstractItemModel::supportedDropActions() const
{
return Qt::CopyAction;
}
/*!
Returns the actions supported by the data in this model.
The default implementation returns supportedDropActions() unless specific
values have been set with setSupportedDragActions().
supportedDragActions() is used by QAbstractItemView::startDrag() as the
default values when a drag occurs.
\sa Qt::DropActions, {Using drag and drop with item views}
*/
Qt::DropActions QAbstractItemModel::supportedDragActions() const
{
// ### Qt 5: make this virtual or these properties
Q_D(const QAbstractItemModel);
if (d->supportedDragActions != -1)
return d->supportedDragActions;
return supportedDropActions();
}
/*!
\since 4.2
Sets the supported drag \a actions for the items in the model.
\sa supportedDragActions(), {Using drag and drop with item views}
*/
void QAbstractItemModel::setSupportedDragActions(Qt::DropActions actions)
{
Q_D(QAbstractItemModel);
d->supportedDragActions = actions;
}
/*!
\note The base class implementation of this function does nothing and
returns false.
On models that support this, inserts \a count rows into the model before
the given \a row. Items in the new row will be children of the item
represented by the \a parent model index.
If \a row is 0, the rows are prepended to any existing rows in the parent.
If \a row is rowCount(), the rows are appended to any existing rows in the
parent.
If \a parent has no children, a single column with \a count rows is
inserted.
Returns true if the rows were successfully inserted; otherwise returns
false.
If you implement your own model, you can reimplement this function if you
want to support insertions. Alternatively, you can provide your own API for
altering the data. In either case, you will need to call
beginInsertRows() and endInsertRows() to notify other components that the
model has changed.
\sa insertColumns(), removeRows(), beginInsertRows(), endInsertRows()
*/
bool QAbstractItemModel::insertRows(int, int, const QModelIndex &)
{
return false;
}
/*!
On models that support this, inserts \a count new columns into the model
before the given \a column. The items in each new column will be children
of the item represented by the \a parent model index.
If \a column is 0, the columns are prepended to any existing columns.
If \a column is columnCount(), the columns are appended to any existing
columns.
If \a parent has no children, a single row with \a count columns is
inserted.
Returns true if the columns were successfully inserted; otherwise returns
false.
The base class implementation does nothing and returns false.
If you implement your own model, you can reimplement this function if you
want to support insertions. Alternatively, you can provide your own API for
altering the data.
\sa insertRows(), removeColumns(), beginInsertColumns(), endInsertColumns()
*/
bool QAbstractItemModel::insertColumns(int, int, const QModelIndex &)
{
return false;
}
/*!
On models that support this, removes \a count rows starting with the given
\a row under parent \a parent from the model.
Returns true if the rows were successfully removed; otherwise returns
false.
The base class implementation does nothing and returns false.
If you implement your own model, you can reimplement this function if you
want to support removing. Alternatively, you can provide your own API for
altering the data.
\sa removeRow(), removeColumns(), insertColumns(), beginRemoveRows(),
endRemoveRows()
*/
bool QAbstractItemModel::removeRows(int, int, const QModelIndex &)
{
return false;
}
/*!
On models that support this, removes \a count columns starting with the
given \a column under parent \a parent from the model.
Returns true if the columns were successfully removed; otherwise returns
false.
The base class implementation does nothing and returns false.
If you implement your own model, you can reimplement this function if you
want to support removing. Alternatively, you can provide your own API for
altering the data.
\sa removeColumn(), removeRows(), insertColumns(), beginRemoveColumns(),
endRemoveColumns()
*/
bool QAbstractItemModel::removeColumns(int, int, const QModelIndex &)
{
return false;
}
/*!
Fetches any available data for the items with the parent specified by the
\a parent index.
Reimplement this if you are populating your model incrementally.
The default implementation does nothing.
\sa canFetchMore()
*/
void QAbstractItemModel::fetchMore(const QModelIndex &)
{
// do nothing
}
/*!
Returns true if there is more data available for \a parent; otherwise
returns false.
The default implementation always returns false.
If canFetchMore() returns true, QAbstractItemView will call fetchMore().
However, the fetchMore() function is only called when the model is being
populated incrementally.
\sa fetchMore()
*/
bool QAbstractItemModel::canFetchMore(const QModelIndex &) const
{
return false;
}
/*!
Returns the item flags for the given \a index.
The base class implementation returns a combination of flags that enables
the item (\c ItemIsEnabled) and allows it to be selected
(\c ItemIsSelectable).
\sa Qt::ItemFlags
*/
Qt::ItemFlags QAbstractItemModel::flags(const QModelIndex &index) const
{
Q_D(const QAbstractItemModel);
if (!d->indexValid(index))
return 0;
return Qt::ItemIsSelectable|Qt::ItemIsEnabled;
}
/*!
Sorts the model by \a column in the given \a order.
The base class implementation does nothing.
*/
void QAbstractItemModel::sort(int column, Qt::SortOrder order)
{
Q_UNUSED(column);
Q_UNUSED(order);
// do nothing
}
/*!
Returns a model index for the buddy of the item represented by \a index.
When the user wants to edit an item, the view will call this function to
check whether another item in the model should be edited instead. Then, the
view will construct a delegate using the model index returned by the buddy
item.
The default implementation of this function has each item as its own buddy.
*/
QModelIndex QAbstractItemModel::buddy(const QModelIndex &index) const
{
return index;
}
/*!
Returns a list of indexes for the items in the column of the \a start index
where data stored under the given \a role matches the specified \a value.
The way the search is performed is defined by the \a flags given. The list
that is returned may be empty.
The search begins from the \a start index, and continues until the number
of matching data items equals \a hits, the search reaches the last row, or
the search reaches \a start again - depending on whether \c MatchWrap is
specified in \a flags. If you want to search for all matching items, use
\a hits = -1.
By default, this function will perform a wrapping, string-based comparison
on all items, searching for items that begin with the search term specified
by \a value.
\note The default implementation of this function only searches columns.
Reimplement this function to include a different search behavior.
*/
QModelIndexList QAbstractItemModel::match(const QModelIndex &start, int role,
const QVariant &value, int hits,
Qt::MatchFlags flags) const
{
QModelIndexList result;
uint matchType = flags & 0x0F;
Qt::CaseSensitivity cs = flags & Qt::MatchCaseSensitive ? Qt::CaseSensitive : Qt::CaseInsensitive;
bool recurse = flags & Qt::MatchRecursive;
bool wrap = flags & Qt::MatchWrap;
bool allHits = (hits == -1);
QString text; // only convert to a string if it is needed
QModelIndex p = parent(start);
int from = start.row();
int to = rowCount(p);
// iterates twice if wrapping
for (int i = 0; (wrap && i < 2) || (!wrap && i < 1); ++i) {
for (int r = from; (r < to) && (allHits || result.count() < hits); ++r) {
QModelIndex idx = index(r, start.column(), p);
if (!idx.isValid())
continue;
QVariant v = data(idx, role);
// QVariant based matching
if (matchType == Qt::MatchExactly) {
if (value == v)
result.append(idx);
} else { // QString based matching
if (text.isEmpty()) // lazy conversion
text = value.toString();
QString t = v.toString();
switch (matchType) {
case Qt::MatchRegExp:
if (QRegExp(text, cs).exactMatch(t))
result.append(idx);
break;
case Qt::MatchWildcard:
if (QRegExp(text, cs, QRegExp::Wildcard).exactMatch(t))
result.append(idx);
break;
case Qt::MatchStartsWith:
if (t.startsWith(text, cs))
result.append(idx);
break;
case Qt::MatchEndsWith:
if (t.endsWith(text, cs))
result.append(idx);
break;
case Qt::MatchFixedString:
if (t.compare(text, cs) == 0)
result.append(idx);
break;
case Qt::MatchContains:
default:
if (t.contains(text, cs))
result.append(idx);
}
}
if (recurse && hasChildren(idx)) { // search the hierarchy
result += match(index(0, idx.column(), idx), role,
(text.isEmpty() ? value : text),
(allHits ? -1 : hits - result.count()), flags);
}
}
// prepare for the next iteration
from = 0;
to = start.row();
}
return result;
}
/*!
Returns the row and column span of the item represented by \a index.
\note Currently, span is not used.
*/
QSize QAbstractItemModel::span(const QModelIndex &) const
{
return QSize(1, 1);
}
/*!
\since 4.6
Sets the model's role names to \a roleNames.
This function allows mapping of role identifiers to role property names in
Declarative UI. This function must be called before the model is used.
Modifying the role names after the model has been set may result in
undefined behaviour.
\sa roleNames()
*/
void QAbstractItemModel::setRoleNames(const QHash<int,QByteArray> &roleNames)
{
Q_D(QAbstractItemModel);
d->roleNames = roleNames;
}
/*!
\since 4.6
Returns the model's role names.
\sa setRoleNames()
*/
const QHash<int,QByteArray> &QAbstractItemModel::roleNames() const
{
Q_D(const QAbstractItemModel);
return d->roleNames;
}
/*!
Lets the model know that it should submit cached information to permanent
storage. This function is typically used for row editing.
Returns true if there is no error; otherwise returns false.
\sa revert()
*/
bool QAbstractItemModel::submit()
{
return true;
}
/*!
Lets the model know that it should discard cached information. This
function is typically used for row editing.
\sa submit()
*/
void QAbstractItemModel::revert()
{
// do nothing
}
/*!
Returns the data for the given \a role and \a section in the header with
the specified \a orientation.
For horizontal headers, the section number corresponds to the column
number. Similarly, for vertical headers, the section number corresponds to
the row number.
\sa Qt::ItemDataRole, setHeaderData(), QHeaderView
*/
QVariant QAbstractItemModel::headerData(int section, Qt::Orientation orientation, int role) const
{
Q_UNUSED(orientation);
if (role == Qt::DisplayRole)
return section + 1;
return QVariant();
}
/*!
Sets the data for the given \a role and \a section in the header with the
specified \a orientation to the \a value supplied.
Returns true if the header's data was updated; otherwise returns false.
When reimplementing this function, the headerDataChanged() signal must be
emitted explicitly.
\sa Qt::ItemDataRole, headerData()
*/
bool QAbstractItemModel::setHeaderData(int section, Qt::Orientation orientation,
const QVariant &value, int role)
{
Q_UNUSED(section);
Q_UNUSED(orientation);
Q_UNUSED(value);
Q_UNUSED(role);
return false;
}
/*!
\fn QModelIndex QAbstractItemModel::createIndex(int row, int column, void *ptr) const
Creates a model index for the given \a row and \a column with the internal
pointer \a ptr.
When using a QSortFilterProxyModel, its indexes have their own internal
pointer. It is not advisable to access this internal pointer outside of the
model. Use the data() function instead.
This function provides a consistent interface that model subclasses must
use to create model indexes.
*/
/*!
\fn QModelIndex QAbstractItemModel::createIndex(int row, int column, int id) const
\obsolete
Use QModelIndex
QAbstractItemModel::createIndex(int row, int column, quint32 id) instead.
*/
/*!
\fn QModelIndex QAbstractItemModel::createIndex(int row, int column, quint32 id) const
Creates a model index for the given \a row and \a column with the internal
identifier, \a id.
This function provides a consistent interface that model subclasses must
use to create model indexes.
\sa QModelIndex::internalId()
*/
/*!
\internal
*/
void QAbstractItemModel::encodeData(const QModelIndexList &indexes, QDataStream &stream) const
{
QModelIndexList::ConstIterator it = indexes.begin();
for (; it != indexes.end(); ++it)
stream << (*it).row() << (*it).column() << itemData(*it);
}
/*!
\internal
*/
bool QAbstractItemModel::decodeData(int row, int column, const QModelIndex &parent,
QDataStream &stream)
{
int top = INT_MAX;
int left = INT_MAX;
int bottom = 0;
int right = 0;
QVector<int> rows, columns;
QVector<QMap<int, QVariant> > data;
while (!stream.atEnd()) {
int r, c;
QMap<int, QVariant> v;
stream >> r >> c >> v;
rows.append(r);
columns.append(c);
data.append(v);
top = qMin(r, top);
left = qMin(c, left);
bottom = qMax(r, bottom);
right = qMax(c, right);
}
// insert the dragged items into the table, use a bit array to avoid overwriting items,
// since items from different tables can have the same row and column
int dragRowCount = 0;
int dragColumnCount = right - left + 1;
// Compute the number of continuous rows upon insertion and modify the rows to match
QVector<int> rowsToInsert(bottom + 1);
for (int i = 0; i < rows.count(); ++i)
rowsToInsert[rows.at(i)] = 1;
for (int i = 0; i < rowsToInsert.count(); ++i) {
if (rowsToInsert[i] == 1){
rowsToInsert[i] = dragRowCount;
++dragRowCount;
}
}
for (int i = 0; i < rows.count(); ++i)
rows[i] = top + rowsToInsert[rows[i]];
QBitArray isWrittenTo(dragRowCount * dragColumnCount);
// make space in the table for the dropped data
int colCount = columnCount(parent);
if (colCount == 0) {
insertColumns(colCount, dragColumnCount - colCount, parent);
colCount = columnCount(parent);
}
insertRows(row, dragRowCount, parent);
row = qMax(0, row);
column = qMax(0, column);
QVector<QPersistentModelIndex> newIndexes(data.size());
// set the data in the table
for (int j = 0; j < data.size(); ++j) {
int relativeRow = rows.at(j) - top;
int relativeColumn = columns.at(j) - left;
int destinationRow = relativeRow + row;
int destinationColumn = relativeColumn + column;
int flat = (relativeRow * dragColumnCount) + relativeColumn;
// if the item was already written to, or we just can't fit it in the table, create a new row
if (destinationColumn >= colCount || isWrittenTo.testBit(flat)) {
destinationColumn = qBound(column, destinationColumn, colCount - 1);
destinationRow = row + dragRowCount;
insertRows(row + dragRowCount, 1, parent);
flat = (dragRowCount * dragColumnCount) + relativeColumn;
isWrittenTo.resize(++dragRowCount * dragColumnCount);
}
if (!isWrittenTo.testBit(flat)) {
newIndexes[j] = index(destinationRow, destinationColumn, parent);
isWrittenTo.setBit(flat);
}
}
for(int k = 0; k < newIndexes.size(); k++) {
if (newIndexes.at(k).isValid())
setItemData(newIndexes.at(k), data.at(k));
}
return true;
}
/*!
Begins a row insertion operation.
When reimplementing insertRows() in a subclass, you must call this function
\e before inserting data into the model's underlying data store.
The \a parent index corresponds to the parent into which the new rows are
inserted; \a first and \a last are the row numbers that the new rows will
have after they have been inserted.
\table 80%
\row
\o \inlineimage modelview-begin-insert-rows.png Inserting rows
\o Specify the first and last row numbers for the span of rows you
want to insert into an item in a model.
For example, as shown in the diagram, we insert three rows before
row 2, so \a first is 2 and \a last is 4:
\snippet doc/src/snippets/code/src_corelib_kernel_qabstractitemmodel.cpp 0
This inserts the three new rows as rows 2, 3, and 4.
\row
\o \inlineimage modelview-begin-append-rows.png Appending rows
\o To append rows, insert them after the last row.
For example, as shown in the diagram, we append two rows to a
collection of 4 existing rows (ending in row 3), so \a first is 4
and \a last is 5:
\snippet doc/src/snippets/code/src_corelib_kernel_qabstractitemmodel.cpp 1
This appends the two new rows as rows 4 and 5.
\endtable
\note This function emits the rowsAboutToBeInserted() signal which
connected views (or proxies) must handle before the data is inserted.
Otherwise, the views may end up in an invalid state.
\sa endInsertRows()
*/
void QAbstractItemModel::beginInsertRows(const QModelIndex &parent, int first, int last)
{
Q_ASSERT(first >= 0);
Q_ASSERT(last >= first);
Q_D(QAbstractItemModel);
d->changes.push(QAbstractItemModelPrivate::Change(parent, first, last));
emit rowsAboutToBeInserted(parent, first, last);
d->rowsAboutToBeInserted(parent, first, last);
}
/*!
Ends a row insertion operation.
When reimplementing insertRows() in a subclass, you must call this function
\e after inserting data into the model's underlying data store.
\sa beginInsertRows()
*/
void QAbstractItemModel::endInsertRows()
{
Q_D(QAbstractItemModel);
QAbstractItemModelPrivate::Change change = d->changes.pop();
d->rowsInserted(change.parent, change.first, change.last);
emit rowsInserted(change.parent, change.first, change.last);
}
/*!
Begins a row removal operation.
When reimplementing removeRows() in a subclass, you must call this
function \e before removing data from the model's underlying data store.
The \a parent index corresponds to the parent from which the new rows are
removed; \a first and \a last are the row numbers of the rows to be
removed.
\table 80%
\row
\o \inlineimage modelview-begin-remove-rows.png Removing rows
\o Specify the first and last row numbers for the span of rows you
want to remove from an item in a model.
For example, as shown in the diagram, we remove the two rows from
row 2 to row 3, so \a first is 2 and \a last is 3:
\snippet doc/src/snippets/code/src_corelib_kernel_qabstractitemmodel.cpp 2
\endtable
\note This function emits the rowsAboutToBeRemoved() signal which connected
views (or proxies) must handle before the data is removed. Otherwise, the
views may end up in an invalid state.
\sa endRemoveRows()
*/
void QAbstractItemModel::beginRemoveRows(const QModelIndex &parent, int first, int last)
{
Q_ASSERT(first >= 0);
Q_ASSERT(last >= first);
Q_D(QAbstractItemModel);
d->changes.push(QAbstractItemModelPrivate::Change(parent, first, last));
emit rowsAboutToBeRemoved(parent, first, last);
d->rowsAboutToBeRemoved(parent, first, last);
}
/*!
Ends a row removal operation.
When reimplementing removeRows() in a subclass, you must call this function
\e after removing data from the model's underlying data store.
\sa beginRemoveRows()
*/
void QAbstractItemModel::endRemoveRows()
{
Q_D(QAbstractItemModel);
QAbstractItemModelPrivate::Change change = d->changes.pop();
d->rowsRemoved(change.parent, change.first, change.last);
emit rowsRemoved(change.parent, change.first, change.last);
}
/*!
Returns whether a move operation is valid.
A move operation is not allowed if it moves a continuous range of rows to a destination within
itself, or if it attempts to move a row to one of its own descendants.
\internal
*/
bool QAbstractItemModelPrivate::allowMove(const QModelIndex &srcParent, int start, int end, const QModelIndex &destinationParent, int destinationStart, Qt::Orientation orientation)
{
// Don't move the range within itself.
if (destinationParent == srcParent)
return !(destinationStart >= start && destinationStart <= end + 1);
QModelIndex destinationAncestor = destinationParent;
int pos = (Qt::Vertical == orientation) ? destinationAncestor.row() : destinationAncestor.column();
forever {
if (destinationAncestor == srcParent) {
if (pos >= start && pos <= end)
return false;
break;
}
if (!destinationAncestor.isValid())
break;
pos = (Qt::Vertical == orientation) ? destinationAncestor.row() : destinationAncestor.column();
destinationAncestor = destinationAncestor.parent();
}
return true;
}
/*!
\since 4.6
Begins a row move operation.
When reimplementing a subclass, this method simplifies moving
entities in your model. This method is responsible for moving
persistent indexes in the model, which you would otherwise be
required to do yourself. Using beginMoveRows and endMoveRows
is an alternative to emitting layoutAboutToBeChanged and
layoutChanged directly along with changePersistentIndexes.
layoutAboutToBeChanged is emitted by this method for compatibility
reasons.
The \a sourceParent index corresponds to the parent from which the
rows are moved; \a sourceFirst and \a sourceLast are the first and last
row numbers of the rows to be moved. The \a destinationParent index
corresponds to the parent into which those rows are moved. The \a
destinationChild is the row to which the rows will be moved. That
is, the index at row \a sourceFirst in \a sourceParent will become
row \a destinationChild in \a destinationParent, followed by all other
rows up to \a sourceLast.
However, when moving rows down in the same parent (\a sourceParent
and \a destinationParent are equal), the rows will be placed before the
\a destinationChild index. That is, if you wish to move rows 0 and 1 so
they will become rows 1 and 2, \a destinationChild should be 3. In this
case, the new index for the source row \c i (which is between
\a sourceFirst and \a sourceLast) is equal to
\c {(destinationChild-sourceLast-1+i)}.
Note that if \a sourceParent and \a destinationParent are the same,
you must ensure that the \a destinationChild is not within the range
of \a sourceFirst and \a sourceLast + 1. You must also ensure that you
do not attempt to move a row to one of its own children or ancestors.
This method returns false if either condition is true, in which case you
should abort your move operation.
\table 80%
\row
\o \inlineimage modelview-move-rows-1.png Moving rows to another parent
\o Specify the first and last row numbers for the span of rows in
the source parent you want to move in the model. Also specify
the row in the destination parent to move the span to.
For example, as shown in the diagram, we move three rows from
row 2 to 4 in the source, so \a sourceFirst is 2 and \a sourceLast is 4.
We move those items to above row 2 in the destination, so \a destinationChild is 2.
\snippet doc/src/snippets/code/src_corelib_kernel_qabstractitemmodel.cpp 6
This moves the three rows rows 2, 3, and 4 in the source to become 2, 3 and 4 in
the destination. Other affected siblings are displaced accordingly.
\row
\o \inlineimage modelview-move-rows-2.png Moving rows to append to another parent
\o To append rows to another parent, move them to after the last row.
For example, as shown in the diagram, we move three rows to a
collection of 6 existing rows (ending in row 5), so \a destinationChild is 6:
\snippet doc/src/snippets/code/src_corelib_kernel_qabstractitemmodel.cpp 7
This moves the target rows to the end of the target parent as 6, 7 and 8.
\row
\o \inlineimage modelview-move-rows-3.png Moving rows in the same parent up
\o To move rows within the same parent, specify the row to move them to.
For example, as shown in the diagram, we move one item from row 2 to row 0,
so \a sourceFirst and \a sourceLast are 2 and \a destinationChild is 0.
\snippet doc/src/snippets/code/src_corelib_kernel_qabstractitemmodel.cpp 8
Note that other rows may be displaced accordingly. Note also that when moving
items within the same parent you should not attempt invalid or no-op moves. In
the above example, item 2 is at row 2 before the move, so it can not be moved
to row 2 (where it is already) or row 3 (no-op as row 3 means above row 3, where
it is already)
\row
\o \inlineimage modelview-move-rows-4.png Moving rows in the same parent down
\o To move rows within the same parent, specify the row to move them to.
For example, as shown in the diagram, we move one item from row 2 to row 4,
so \a sourceFirst and \a sourceLast are 2 and \a destinationChild is 4.
\snippet doc/src/snippets/code/src_corelib_kernel_qabstractitemmodel.cpp 9
Note that other rows may be displaced accordingly.
\endtable
\sa endMoveRows()
*/
bool QAbstractItemModel::beginMoveRows(const QModelIndex &sourceParent, int sourceFirst, int sourceLast, const QModelIndex &destinationParent, int destinationChild)
{
Q_ASSERT(sourceFirst >= 0);
Q_ASSERT(sourceLast >= sourceFirst);
Q_ASSERT(destinationChild >= 0);
Q_D(QAbstractItemModel);
if (!d->allowMove(sourceParent, sourceFirst, sourceLast, destinationParent, destinationChild, Qt::Vertical)) {
return false;
}
QAbstractItemModelPrivate::Change sourceChange(sourceParent, sourceFirst, sourceLast);
sourceChange.needsAdjust = sourceParent.isValid() && sourceParent.row() >= destinationChild && sourceParent.parent() == destinationParent;
d->changes.push(sourceChange);
int destinationLast = destinationChild + (sourceLast - sourceFirst);
QAbstractItemModelPrivate::Change destinationChange(destinationParent, destinationChild, destinationLast);
destinationChange.needsAdjust = destinationParent.isValid() && destinationParent.row() >= sourceLast && destinationParent.parent() == sourceParent;
d->changes.push(destinationChange);
emit rowsAboutToBeMoved(sourceParent, sourceFirst, sourceLast, destinationParent, destinationChild);
emit layoutAboutToBeChanged();
d->itemsAboutToBeMoved(sourceParent, sourceFirst, sourceLast, destinationParent, destinationChild, Qt::Vertical);
return true;
}
/*!
Ends a row move operation.
When implementing a subclass, you must call this
function \e after moving data within the model's underlying data
store.
layoutChanged is emitted by this method for compatibility reasons.
\sa beginMoveRows()
\since 4.6
*/
void QAbstractItemModel::endMoveRows()
{
Q_D(QAbstractItemModel);
QAbstractItemModelPrivate::Change insertChange = d->changes.pop();
QAbstractItemModelPrivate::Change removeChange = d->changes.pop();
QModelIndex adjustedSource = removeChange.parent;
QModelIndex adjustedDestination = insertChange.parent;
const int numMoved = removeChange.last - removeChange.first + 1;
if (insertChange.needsAdjust)
adjustedDestination = createIndex(adjustedDestination.row() - numMoved, adjustedDestination.column(), adjustedDestination.internalPointer());
if (removeChange.needsAdjust)
adjustedSource = createIndex(adjustedSource.row() + numMoved, adjustedSource.column(), adjustedSource.internalPointer());
d->itemsMoved(adjustedSource, removeChange.first, removeChange.last, adjustedDestination, insertChange.first, Qt::Vertical);
emit rowsMoved(adjustedSource, removeChange.first, removeChange.last, adjustedDestination, insertChange.first);
emit layoutChanged();
}
/*!
Begins a column insertion operation.
When reimplementing insertColumns() in a subclass, you must call this
function \e before inserting data into the model's underlying data store.
The \a parent index corresponds to the parent into which the new columns
are inserted; \a first and \a last are the column numbers of the new
columns will have after they have been inserted.
\table 80%
\row
\o \inlineimage modelview-begin-insert-columns.png Inserting columns
\o Specify the first and last column numbers for the span of columns
you want to insert into an item in a model.
For example, as shown in the diagram, we insert three columns
before column 4, so \a first is 4 and \a last is 6:
\snippet doc/src/snippets/code/src_corelib_kernel_qabstractitemmodel.cpp 3
This inserts the three new columns as columns 4, 5, and 6.
\row
\o \inlineimage modelview-begin-append-columns.png Appending columns
\o To append columns, insert them after the last column.
For example, as shown in the diagram, we append three columns to a
collection of six existing columns (ending in column 5), so
\a first is 6 and \a last is 8:
\snippet doc/src/snippets/code/src_corelib_kernel_qabstractitemmodel.cpp 4
This appends the two new columns as columns 6, 7, and 8.
\endtable
\note This function emits the columnsAboutToBeInserted() signal which
connected views (or proxies) must handle before the data is inserted.
Otherwise, the views may end up in an invalid state.
\sa endInsertColumns()
*/
void QAbstractItemModel::beginInsertColumns(const QModelIndex &parent, int first, int last)
{
Q_ASSERT(first >= 0);
Q_ASSERT(last >= first);
Q_D(QAbstractItemModel);
d->changes.push(QAbstractItemModelPrivate::Change(parent, first, last));
emit columnsAboutToBeInserted(parent, first, last);
d->columnsAboutToBeInserted(parent, first, last);
}
/*!
Ends a column insertion operation.
When reimplementing insertColumns() in a subclass, you must call this
function \e after inserting data into the model's underlying data
store.
\sa beginInsertColumns()
*/
void QAbstractItemModel::endInsertColumns()
{
Q_D(QAbstractItemModel);
QAbstractItemModelPrivate::Change change = d->changes.pop();
d->columnsInserted(change.parent, change.first, change.last);
emit columnsInserted(change.parent, change.first, change.last);
}
/*!
Begins a column removal operation.
When reimplementing removeColumns() in a subclass, you must call this
function \e before removing data from the model's underlying data store.
The \a parent index corresponds to the parent from which the new columns
are removed; \a first and \a last are the column numbers of the first and
last columns to be removed.
\table 80%
\row
\o \inlineimage modelview-begin-remove-columns.png Removing columns
\o Specify the first and last column numbers for the span of columns
you want to remove from an item in a model.
For example, as shown in the diagram, we remove the three columns
from column 4 to column 6, so \a first is 4 and \a last is 6:
\snippet doc/src/snippets/code/src_corelib_kernel_qabstractitemmodel.cpp 5
\endtable
\note This function emits the columnsAboutToBeRemoved() signal which
connected views (or proxies) must handle before the data is removed.
Otherwise, the views may end up in an invalid state.
\sa endRemoveColumns()
*/
void QAbstractItemModel::beginRemoveColumns(const QModelIndex &parent, int first, int last)
{
Q_ASSERT(first >= 0);
Q_ASSERT(last >= first);
Q_D(QAbstractItemModel);
d->changes.push(QAbstractItemModelPrivate::Change(parent, first, last));
emit columnsAboutToBeRemoved(parent, first, last);
d->columnsAboutToBeRemoved(parent, first, last);
}
/*!
Ends a column removal operation.
When reimplementing removeColumns() in a subclass, you must call this
function \e after removing data from the model's underlying data store.
\sa beginRemoveColumns()
*/
void QAbstractItemModel::endRemoveColumns()
{
Q_D(QAbstractItemModel);
QAbstractItemModelPrivate::Change change = d->changes.pop();
d->columnsRemoved(change.parent, change.first, change.last);
emit columnsRemoved(change.parent, change.first, change.last);
}
/*!
Begins a column move operation.
When reimplementing a subclass, this method simplifies moving
entities in your model. This method is responsible for moving
persistent indexes in the model, which you would otherwise be
required to do yourself. Using beginMoveRows and endMoveRows
is an alternative to emitting layoutAboutToBeChanged and
layoutChanged directly along with changePersistentIndexes.
layoutAboutToBeChanged is emitted by this method for compatibility
reasons.
The \a sourceParent index corresponds to the parent from which the
columns are moved; \a sourceFirst and \a sourceLast are the first and last
column numbers of the columns to be moved. The \a destinationParent index
corresponds to the parent into which those columns are moved. The \a
destinationChild is the column to which the columns will be moved. That
is, the index at column \a sourceFirst in \a sourceParent will become
column \a destinationChild in \a destinationParent, followed by all other
columns up to \a sourceLast.
However, when moving columns down in the same parent (\a sourceParent
and \a destinationParent are equal), the columnss will be placed before the
\a destinationChild index. That is, if you wish to move columns 0 and 1 so
they will become columns 1 and 2, \a destinationChild should be 3. In this
case, the new index for the source column \c i (which is between
\a sourceFirst and \a sourceLast) is equal to
\c {(destinationChild-sourceLast-1+i)}.
Note that if \a sourceParent and \a destinationParent are the same,
you must ensure that the \a destinationChild is not within the range
of \a sourceFirst and \a sourceLast + 1. You must also ensure that you
do not attempt to move a column to one of its own children or ancestors.
This method returns false if either condition is true, in which case you
should abort your move operation.
\sa endMoveColumns()
\since 4.6
*/
bool QAbstractItemModel::beginMoveColumns(const QModelIndex &sourceParent, int sourceFirst, int sourceLast, const QModelIndex &destinationParent, int destinationChild)
{
Q_ASSERT(sourceFirst >= 0);
Q_ASSERT(sourceLast >= sourceFirst);
Q_ASSERT(destinationChild >= 0);
Q_D(QAbstractItemModel);
if (!d->allowMove(sourceParent, sourceFirst, sourceLast, destinationParent, destinationChild, Qt::Horizontal)) {
return false;
}
QAbstractItemModelPrivate::Change sourceChange(sourceParent, sourceFirst, sourceLast);
sourceChange.needsAdjust = sourceParent.isValid() && sourceParent.row() >= destinationChild && sourceParent.parent() == destinationParent;
d->changes.push(sourceChange);
int destinationLast = destinationChild + (sourceLast - sourceFirst);
QAbstractItemModelPrivate::Change destinationChange(destinationParent, destinationChild, destinationLast);
destinationChange.needsAdjust = destinationParent.isValid() && destinationParent.row() >= sourceLast && destinationParent.parent() == sourceParent;
d->changes.push(destinationChange);
d->itemsAboutToBeMoved(sourceParent, sourceFirst, sourceLast, destinationParent, destinationChild, Qt::Horizontal);
emit columnsAboutToBeMoved(sourceParent, sourceFirst, sourceLast, destinationParent, destinationChild);
emit layoutAboutToBeChanged();
return true;
}
/*!
Ends a column move operation.
When implementing a subclass, you must call this
function \e after moving data within the model's underlying data
store.
layoutChanged is emitted by this method for compatibility reasons.
\sa beginMoveColumns()
\since 4.6
*/
void QAbstractItemModel::endMoveColumns()
{
Q_D(QAbstractItemModel);
QAbstractItemModelPrivate::Change insertChange = d->changes.pop();
QAbstractItemModelPrivate::Change removeChange = d->changes.pop();
QModelIndex adjustedSource = removeChange.parent;
QModelIndex adjustedDestination = insertChange.parent;
const int numMoved = removeChange.last - removeChange.first + 1;
if (insertChange.needsAdjust)
adjustedDestination = createIndex(adjustedDestination.row(), adjustedDestination.column() - numMoved, adjustedDestination.internalPointer());
if (removeChange.needsAdjust)
adjustedSource = createIndex(adjustedSource.row(), adjustedSource.column() + numMoved, adjustedSource.internalPointer());
d->itemsMoved(adjustedSource, removeChange.first, removeChange.last, adjustedDestination, insertChange.first, Qt::Horizontal);
emit columnsMoved(adjustedSource, removeChange.first, removeChange.last, adjustedDestination, insertChange.first);
emit layoutChanged();
}
/*!
Resets the model to its original state in any attached views.
\note Use beginResetModel() and endResetModel() instead whenever possible.
Use this method only if there is no way to call beginResetModel() before invalidating the model.
Otherwise it could lead to unexpected behaviour, especially when used with proxy models.
*/
void QAbstractItemModel::reset()
{
Q_D(QAbstractItemModel);
emit modelAboutToBeReset();
d->invalidatePersistentIndexes();
QMetaObject::invokeMethod(this, "resetInternalData");
emit modelReset();
}
/*!
Begins a model reset operation.
A reset operation resets the model to its current state in any attached views.
\note Any views attached to this model will be reset as well.
When a model is reset it means that any previous data reported from the
model is now invalid and has to be queried for again. This also means that
the current item and any selected items will become invalid.
When a model radically changes its data it can sometimes be easier to just
call this function rather than emit dataChanged() to inform other
components when the underlying data source, or its structure, has changed.
You must call this function before resetting any internal data structures in your model
or proxy model.
\sa modelAboutToBeReset(), modelReset(), endResetModel()
\since 4.6
*/
void QAbstractItemModel::beginResetModel()
{
emit modelAboutToBeReset();
}
/*!
Completes a model reset operation.
You must call this function after resetting any internal data structure in your model
or proxy model.
\sa beginResetModel()
\since 4.6
*/
void QAbstractItemModel::endResetModel()
{
Q_D(QAbstractItemModel);
d->invalidatePersistentIndexes();
QMetaObject::invokeMethod(this, "resetInternalData");
emit modelReset();
}
/*!
Changes the QPersistentModelIndex that is equal to the given \a from model
index to the given \a to model index.
If no persistent model index equal to the given \a from model index was
found, nothing is changed.
\sa persistentIndexList(), changePersistentIndexList()
*/
void QAbstractItemModel::changePersistentIndex(const QModelIndex &from, const QModelIndex &to)
{
Q_D(QAbstractItemModel);
if (d->persistent.indexes.isEmpty())
return;
// find the data and reinsert it sorted
const QHash<QModelIndex, QPersistentModelIndexData *>::iterator it = d->persistent.indexes.find(from);
if (it != d->persistent.indexes.end()) {
QPersistentModelIndexData *data = *it;
d->persistent.indexes.erase(it);
data->index = to;
if (to.isValid())
d->persistent.insertMultiAtEnd(to, data);
else
data->model = 0;
}
}
/*!
\since 4.1
Changes the QPersistentModelIndexes that is equal to the indexes in the
given \a from model index list to the given \a to model index list.
If no persistent model indexes equal to the indexes in the given \a from
model index list was found, nothing is changed.
\sa persistentIndexList(), changePersistentIndex()
*/
void QAbstractItemModel::changePersistentIndexList(const QModelIndexList &from,
const QModelIndexList &to)
{
Q_D(QAbstractItemModel);
if (d->persistent.indexes.isEmpty())
return;
QVector<QPersistentModelIndexData *> toBeReinserted;
toBeReinserted.reserve(to.count());
for (int i = 0; i < from.count(); ++i) {
if (from.at(i) == to.at(i))
continue;
const QHash<QModelIndex, QPersistentModelIndexData *>::iterator it = d->persistent.indexes.find(from.at(i));
if (it != d->persistent.indexes.end()) {
QPersistentModelIndexData *data = *it;
d->persistent.indexes.erase(it);
data->index = to.at(i);
if (data->index.isValid())
toBeReinserted << data;
else
data->model = 0;
}
}
for (QVector<QPersistentModelIndexData *>::const_iterator it = toBeReinserted.constBegin();
it != toBeReinserted.constEnd() ; ++it) {
QPersistentModelIndexData *data = *it;
d->persistent.insertMultiAtEnd(data->index, data);
}
}
/*!
\since 4.2
Returns the list of indexes stored as persistent indexes in the model.
*/
QModelIndexList QAbstractItemModel::persistentIndexList() const
{
Q_D(const QAbstractItemModel);
QModelIndexList result;
for (QHash<QModelIndex, QPersistentModelIndexData *>::const_iterator it = d->persistent.indexes.constBegin();
it != d->persistent.indexes.constEnd(); ++it) {
QPersistentModelIndexData *data = *it;
result.append(data->index);
}
return result;
}
/*!
\class QAbstractTableModel
\brief The QAbstractTableModel class provides an abstract model that can be
subclassed to create table models.
\ingroup model-view
QAbstractTableModel provides a standard interface for models that represent
their data as a two-dimensional array of items. It is not used directly,
but must be subclassed.
Since the model provides a more specialized interface than
QAbstractItemModel, it is not suitable for use with tree views, although it
can be used to provide data to a QListView. If you need to represent a
simple list of items, and only need a model to contain a single column of
data, subclassing the QAbstractListModel may be more appropriate.
The rowCount() and columnCount() functions return the dimensions of the
table. To retrieve a model index corresponding to an item in the model, use
index() and provide only the row and column numbers.
\section1 Subclassing
When subclassing QAbstractTableModel, you must implement rowCount(),
columnCount(), and data(). Default implementations of the index() and
parent() functions are provided by QAbstractTableModel.
Well behaved models will also implement headerData().
Editable models need to implement setData(), and implement flags() to
return a value containing
\l{Qt::ItemFlags}{Qt::ItemIsEditable}.
Models that provide interfaces to resizable data structures can
provide implementations of insertRows(), removeRows(), insertColumns(),
and removeColumns(). When implementing these functions, it is
important to call the appropriate functions so that all connected views
are aware of any changes:
\list
\o An insertRows() implementation must call beginInsertRows()
\e before inserting new rows into the data structure, and it must
call endInsertRows() \e{immediately afterwards}.
\o An insertColumns() implementation must call beginInsertColumns()
\e before inserting new columns into the data structure, and it must
call endInsertColumns() \e{immediately afterwards}.
\o A removeRows() implementation must call beginRemoveRows()
\e before the rows are removed from the data structure, and it must
call endRemoveRows() \e{immediately afterwards}.
\o A removeColumns() implementation must call beginRemoveColumns()
\e before the columns are removed from the data structure, and it must
call endRemoveColumns() \e{immediately afterwards}.
\endlist
\note Some general guidelines for subclassing models are available in the
\l{Model Subclassing Reference}.
\note
\sa {Model Classes}, QAbstractItemModel, QAbstractListModel,
{Pixelator Example}
*/
/*!
Constructs an abstract table model for the given \a parent.
*/
QAbstractTableModel::QAbstractTableModel(QObject *parent)
: QAbstractItemModel(parent)
{
}
/*!
\internal
Constructs an abstract table model with \a dd and the given \a parent.
*/
QAbstractTableModel::QAbstractTableModel(QAbstractItemModelPrivate &dd, QObject *parent)
: QAbstractItemModel(dd, parent)
{
}
/*!
Destroys the abstract table model.
*/
QAbstractTableModel::~QAbstractTableModel()
{
}
/*!
\fn QModelIndex QAbstractTableModel::index(int row, int column, const QModelIndex &parent = QModelIndex()) const
Returns the index of the data in \a row and \a column with \a parent.
\sa parent()
*/
QModelIndex QAbstractTableModel::index(int row, int column, const QModelIndex &parent) const
{
return hasIndex(row, column, parent) ? createIndex(row, column, 0) : QModelIndex();
}
/*!
\fn QModelIndex QAbstractTableModel::parent(const QModelIndex &index) const
Returns the parent of the model item with the given \a index.
\sa index() hasChildren()
*/
QModelIndex QAbstractTableModel::parent(const QModelIndex &) const
{
return QModelIndex();
}
bool QAbstractTableModel::hasChildren(const QModelIndex &parent) const
{
if (parent.model() == this || !parent.isValid())
return rowCount(parent) > 0 && columnCount(parent) > 0;
return false;
}
/*!
\class QAbstractListModel
\brief The QAbstractListModel class provides an abstract model that can be
subclassed to create one-dimensional list models.
\ingroup model-view
QAbstractListModel provides a standard interface for models that represent
their data as a simple non-hierarchical sequence of items. It is not used
directly, but must be subclassed.
Since the model provides a more specialized interface than
QAbstractItemModel, it is not suitable for use with tree views; you will
need to subclass QAbstractItemModel if you want to provide a model for
that purpose. If you need to use a number of list models to manage data,
it may be more appropriate to subclass QAbstractTableModel class instead.
Simple models can be created by subclassing this class and implementing
the minimum number of required functions. For example, we could implement
a simple read-only QStringList-based model that provides a list of strings
to a QListView widget. In such a case, we only need to implement the
rowCount() function to return the number of items in the list, and the
data() function to retrieve items from the list.
Since the model represents a one-dimensional structure, the rowCount()
function returns the total number of items in the model. The columnCount()
function is implemented for interoperability with all kinds of views, but
by default informs views that the model contains only one column.
\section1 Subclassing
When subclassing QAbstractListModel, you must provide implementations
of the rowCount() and data() functions. Well behaved models also provide
a headerData() implementation.
For editable list models, you must also provide an implementation of
setData(), implement the flags() function so that it returns a value
containing \l{Qt::ItemFlags}{Qt::ItemIsEditable}.
Note that QAbstractListModel provides a default implementation of
columnCount() that informs views that there is only a single column
of items in this model.
Models that provide interfaces to resizable list-like data structures
can provide implementations of insertRows() and removeRows(). When
implementing these functions, it is important to call the appropriate
functions so that all connected views are aware of any changes:
\list
\o An insertRows() implementation must call beginInsertRows()
\e before inserting new rows into the data structure, and it must
call endInsertRows() \e{immediately afterwards}.
\o A removeRows() implementation must call beginRemoveRows()
\e before the rows are removed from the data structure, and it must
call endRemoveRows() \e{immediately afterwards}.
\endlist
\note Some general guidelines for subclassing models are available in the
\l{Model Subclassing Reference}.
\sa {Model Classes}, {Model Subclassing Reference}, QAbstractItemView,
QAbstractTableModel, {Item Views Puzzle Example}
*/
/*!
Constructs an abstract list model with the given \a parent.
*/
QAbstractListModel::QAbstractListModel(QObject *parent)
: QAbstractItemModel(parent)
{
}
/*!
\internal
Constructs an abstract list model with \a dd and the given \a parent.
*/
QAbstractListModel::QAbstractListModel(QAbstractItemModelPrivate &dd, QObject *parent)
: QAbstractItemModel(dd, parent)
{
}
/*!
Destroys the abstract list model.
*/
QAbstractListModel::~QAbstractListModel()
{
}
/*!
\fn QModelIndex QAbstractListModel::index(int row, int column, const QModelIndex &parent = QModelIndex()) const
Returns the index of the data in \a row and \a column with \a parent.
\sa parent()
*/
QModelIndex QAbstractListModel::index(int row, int column, const QModelIndex &parent) const
{
return hasIndex(row, column, parent) ? createIndex(row, column, 0) : QModelIndex();
}
/*!
Returns the parent of the model item with the given \a index.
\sa index() hasChildren()
*/
QModelIndex QAbstractListModel::parent(const QModelIndex & /* index */) const
{
return QModelIndex();
}
/*!
\internal
Returns the number of columns in the list with the given \a parent.
\sa rowCount()
*/
int QAbstractListModel::columnCount(const QModelIndex &parent) const
{
return parent.isValid() ? 0 : 1;
}
bool QAbstractListModel::hasChildren(const QModelIndex &parent) const
{
return parent.isValid() ? false : (rowCount() > 0);
}
/*!
\typedef QModelIndexList
\relates QModelIndex
Synonym for QList<QModelIndex>.
*/
/*!
\reimp
*/
bool QAbstractTableModel::dropMimeData(const QMimeData *data, Qt::DropAction action,
int row, int column, const QModelIndex &parent)
{
if (!data || !(action == Qt::CopyAction || action == Qt::MoveAction))
return false;
QStringList types = mimeTypes();
if (types.isEmpty())
return false;
QString format = types.at(0);
if (!data->hasFormat(format))
return false;
QByteArray encoded = data->data(format);
QDataStream stream(&encoded, QIODevice::ReadOnly);
// if the drop is on an item, replace the data in the items
if (parent.isValid() && row == -1 && column == -1) {
int top = INT_MAX;
int left = INT_MAX;
QVector<int> rows, columns;
QVector<QMap<int, QVariant> > data;
while (!stream.atEnd()) {
int r, c;
QMap<int, QVariant> v;
stream >> r >> c >> v;
rows.append(r);
columns.append(c);
data.append(v);
top = qMin(r, top);
left = qMin(c, left);
}
for (int i = 0; i < data.size(); ++i) {
int r = (rows.at(i) - top) + parent.row();
int c = (columns.at(i) - left) + parent.column();
if (hasIndex(r, c))
setItemData(index(r, c), data.at(i));
}
return true;
}
// otherwise insert new rows for the data
return decodeData(row, column, parent, stream);
}
/*!
\reimp
*/
bool QAbstractListModel::dropMimeData(const QMimeData *data, Qt::DropAction action,
int row, int column, const QModelIndex &parent)
{
if (!data || !(action == Qt::CopyAction || action == Qt::MoveAction))
return false;
QStringList types = mimeTypes();
if (types.isEmpty())
return false;
QString format = types.at(0);
if (!data->hasFormat(format))
return false;
QByteArray encoded = data->data(format);
QDataStream stream(&encoded, QIODevice::ReadOnly);
// if the drop is on an item, replace the data in the items
if (parent.isValid() && row == -1 && column == -1) {
int top = INT_MAX;
int left = INT_MAX;
QVector<int> rows, columns;
QVector<QMap<int, QVariant> > data;
while (!stream.atEnd()) {
int r, c;
QMap<int, QVariant> v;
stream >> r >> c >> v;
rows.append(r);
columns.append(c);
data.append(v);
top = qMin(r, top);
left = qMin(c, left);
}
for (int i = 0; i < data.size(); ++i) {
int r = (rows.at(i) - top) + parent.row();
if (columns.at(i) == left && hasIndex(r, 0))
setItemData(index(r), data.at(i));
}
return true;
}
if (row == -1)
row = rowCount(parent);
// otherwise insert new rows for the data
return decodeData(row, column, parent, stream);
}
/*!
\fn QAbstractItemModel::modelAboutToBeReset()
\since 4.2
This signal is emitted when reset() is called, before the model's internal
state (e.g. persistent model indexes) has been invalidated.
\sa beginResetModel(), modelReset()
*/
/*!
\fn QAbstractItemModel::modelReset()
\since 4.1
This signal is emitted when reset() is called, after the model's internal
state (e.g. persistent model indexes) has been invalidated.
\sa endResetModel(), modelAboutToBeReset()
*/
/*!
\fn bool QModelIndex::operator<(const QModelIndex &other) const
\since 4.1
Returns true if this model index is smaller than the \a other
model index; otherwise returns false.
*/
/*!
\fn uint qHash(const QPersistentModelIndex &index)
\since 4.5
Returns a hash of the QPersistentModelIndex
*/
/*!
\internal
QHash::insertMulti insert the value before the old value. and find() return the new value.
We need insertMultiAtEnd because we don't want to overwrite the old one, which should be removed later
There should be only one instance QPersistentModelIndexData per index, but in some intermediate state there may be
severals of PersistantModelIndex pointing to the same index, but one is already updated, and the other one is not.
This make sure than when updating the first one we don't overwrite the second one in the hash, and the second one
will be updated right later.
*/
void QAbstractItemModelPrivate::Persistent::insertMultiAtEnd(const QModelIndex& key, QPersistentModelIndexData *data)
{
QHash<QModelIndex,QPersistentModelIndexData *>::iterator newIt =
indexes.insertMulti(key, data);
QHash<QModelIndex,QPersistentModelIndexData *>::iterator it = newIt + 1;
while (it != indexes.end() && it.key() == key) {
qSwap(*newIt,*it);
newIt = it;
++it;
}
}
#include "moc_qabstractitemmodel.h"
QT_END_NAMESPACE
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