qtreewidget.cpp

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// Copyright (C) 2019 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
#include "qtreewidget.h"
 
#include <qheaderview.h>
#include <qpainter.h>
#include <qitemdelegate.h>
#include <qstack.h>
#include <qdebug.h>
#include <private/qtreewidget_p.h>
#include <private/qwidgetitemdata_p.h>
#include <private/qtreewidgetitemiterator_p.h>
 
#include <QtCore/private/qduplicatetracker_p.h>
 
#include <algorithm>
 
QT_BEGIN_NAMESPACE
 
class QTreeModelLessThan
{
public:
    inline bool operator()(QTreeWidgetItem *i1, QTreeWidgetItem *i2) const
        { return *i1 < *i2; }
};
 
class QTreeModelGreaterThan
{
public:
    inline bool operator()(QTreeWidgetItem *i1, QTreeWidgetItem *i2) const
        { return *i2 < *i1; }
};
 
/*
    \class QTreeModel
    \brief The QTreeModel class manages the items stored in a tree view.
 
    \ingroup model-view
    \inmodule QtWidgets
 
*/
 
QTreeModel::QTreeModel(int columns, QTreeWidget *parent)
    : QAbstractItemModel(*new QTreeModelPrivate, parent),
      rootItem(new QTreeWidgetItem),
      headerItem(new QTreeWidgetItem)
{
    rootItem->view = parent;
    rootItem->itemFlags = Qt::ItemIsDropEnabled;
    headerItem->view = parent;
    setColumnCount(columns);
}
 
QTreeModel::QTreeModel(QTreeModelPrivate &dd, QTreeWidget *parent)
    : QAbstractItemModel(dd, parent), rootItem(new QTreeWidgetItem), headerItem(new QTreeWidgetItem)
{
    rootItem->view = parent;
    rootItem->itemFlags = Qt::ItemIsDropEnabled;
    headerItem->view = parent;
}
 
QTreeModel::~QTreeModel()
{
    clear();
    headerItem->view = nullptr;
    delete headerItem;
    rootItem->view = nullptr;
    delete rootItem;
}
 
void QTreeModel::clear()
{
    SkipSorting skipSorting(this);
    beginResetModel();
    for (int i = 0; i < rootItem->childCount(); ++i) {
        QTreeWidgetItem *item = rootItem->children.at(i);
        item->par = nullptr;
        item->view = nullptr;
        delete item;
    }
    rootItem->children.clear();
    sortPendingTimer.stop();
    endResetModel();
}
 
void QTreeModel::setColumnCount(int columns)
{
    SkipSorting skipSorting(this);
    if (columns < 0)
        return;
    if (!headerItem) {
        headerItem = new QTreeWidgetItem();
        headerItem->view = view();
    }
    int count = columnCount();
    if (count == columns)
        return;
 
    if (columns < count) {
        beginRemoveColumns(QModelIndex(), columns, count - 1);
        headerItem->values.resize(columns);
        endRemoveColumns();
    } else {
        beginInsertColumns(QModelIndex(), count, columns - 1);
        headerItem->values.resize(columns);
        for (int i = count; i < columns; ++i) {// insert data without emitting the dataChanged signal
            headerItem->values[i].append(QWidgetItemData(Qt::DisplayRole, QString::number(i + 1)));
            headerItem->d->display.append(QString::number(i + 1));
        }
        endInsertColumns();
    }
}
 
QTreeWidgetItem *QTreeModel::item(const QModelIndex &index) const
{
    if (!index.isValid())
        return nullptr;
    return static_cast<QTreeWidgetItem*>(index.internalPointer());
}
 
QModelIndex QTreeModel::index(const QTreeWidgetItem *item, int column) const
{
    executePendingSort();
 
    if (!item || (item == rootItem))
        return QModelIndex();
    const QTreeWidgetItem *par = item->parent();
    QTreeWidgetItem *itm = const_cast<QTreeWidgetItem*>(item);
    if (!par)
        par = rootItem;
    int row;
    int guess = item->d->rowGuess;
    if (guess >= 0
        && par->children.size() > guess
        && par->children.at(guess) == itm) {
        row = guess;
    } else {
        row = par->children.lastIndexOf(itm);
        itm->d->rowGuess = row;
    }
    return createIndex(row, column, itm);
}
 
QModelIndex QTreeModel::index(int row, int column, const QModelIndex &parent) const
{
    executePendingSort();
 
    int c = columnCount(parent);
    if (row < 0 || column < 0 || column >= c)
        return QModelIndex();
 
    QTreeWidgetItem *parentItem = parent.isValid() ? item(parent) : rootItem;
    if (parentItem && row < parentItem->childCount()) {
        QTreeWidgetItem *itm = parentItem->child(row);
        if (itm)
            return createIndex(row, column, itm);
        return QModelIndex();
    }
 
    return QModelIndex();
}
 
QModelIndex QTreeModel::parent(const QModelIndex &child) const
{
    SkipSorting skipSorting(this); //The reason we don't sort here is that this might be called from a valid QPersistentModelIndex
                                   //We don't want it to become suddenly invalid
 
    if (!child.isValid())
        return QModelIndex();
    QTreeWidgetItem *itm = static_cast<QTreeWidgetItem *>(child.internalPointer());
    if (!itm || itm == rootItem)
        return QModelIndex();
    QTreeWidgetItem *parent = itm->parent();
    return index(parent, 0);
}
 
int QTreeModel::rowCount(const QModelIndex &parent) const
{
    if (!parent.isValid())
        return rootItem->childCount();
 
    QTreeWidgetItem *parentItem = item(parent);
    if (parentItem)
        return parentItem->childCount();
    return 0;
}
 
int QTreeModel::columnCount(const QModelIndex &index) const
{
    Q_UNUSED(index);
    if (!headerItem)
        return 0;
    return headerItem->columnCount();
}
 
bool QTreeModel::hasChildren(const QModelIndex &parent) const
{
    if (!parent.isValid())
        return (rootItem->childCount() > 0);
 
    QTreeWidgetItem *itm = item(parent);
    if (!itm)
        return false;
    switch (itm->d->policy) {
    case QTreeWidgetItem::ShowIndicator:
        return true;
    case QTreeWidgetItem::DontShowIndicator:
        return false;
    case QTreeWidgetItem::DontShowIndicatorWhenChildless:
        return (itm->childCount() > 0);
    }
    return false;
}
 
QVariant QTreeModel::data(const QModelIndex &index, int role) const
{
    if (!index.isValid())
        return QVariant();
    QTreeWidgetItem *itm = item(index);
    if (itm)
        return itm->data(index.column(), role);
    return QVariant();
}
 
bool QTreeModel::setData(const QModelIndex &index, const QVariant &value, int role)
{
    if (!index.isValid())
        return false;
    QTreeWidgetItem *itm = item(index);
    if (itm) {
        itm->setData(index.column(), role, value);
        return true;
    }
    return false;
}
 
bool QTreeModel::clearItemData(const QModelIndex &index)
{
    if (!checkIndex(index, CheckIndexOption::IndexIsValid))
        return false;
    QTreeWidgetItem *itm = item(index);
    if (!itm)
        return false;
    const auto beginIter = itm->values.at(index.column()).cbegin();
    const auto endIter = itm->values.at(index.column()).cend();
    if (std::all_of(beginIter, endIter, [](const QWidgetItemData& data) -> bool { return !data.value.isValid(); })
        && !itm->d->display.at(index.column()).isValid()) {
        return true; //it's already cleared
    }
    itm->d->display[index.column()] = QVariant();
    itm->values[index.column()].clear();
    emit dataChanged(index, index, QList<int> {});
    return true;
}
 
QMap<int, QVariant> QTreeModel::itemData(const QModelIndex &index) const
{
    QMap<int, QVariant> roles;
    QTreeWidgetItem *itm = item(index);
    if (itm) {
        int column = index.column();
        if (column < itm->values.size()) {
            for (int i = 0; i < itm->values.at(column).size(); ++i) {
                roles.insert(itm->values.at(column).at(i).role,
                             itm->values.at(column).at(i).value);
            }
        }
 
        // the two special cases
        QVariant displayValue = itm->data(column, Qt::DisplayRole);
        if (displayValue.isValid())
            roles.insert(Qt::DisplayRole, displayValue);
 
        QVariant checkValue = itm->data(column, Qt::CheckStateRole);
        if (checkValue.isValid())
            roles.insert(Qt::CheckStateRole, checkValue);
    }
    return roles;
}
 
bool QTreeModel::insertRows(int row, int count, const QModelIndex &parent)
{
    SkipSorting skipSorting(this);
    if (count < 1 || row < 0 || row > rowCount(parent) || parent.column() > 0)
        return false;
 
    beginInsertRows(parent, row, row + count - 1);
    QTreeWidgetItem *par = item(parent);
    while (count > 0) {
        QTreeWidgetItem *item = new QTreeWidgetItem();
        item->view = view();
        item->par = par;
        if (par)
            par->children.insert(row++, item);
        else
            rootItem->children.insert(row++, item);
        --count;
    }
    endInsertRows();
    return true;
}
 
bool QTreeModel::insertColumns(int column, int count, const QModelIndex &parent)
{
    SkipSorting skipSorting(this);
    if (count < 1 || column < 0 || column > columnCount(parent) || parent.column() > 0 || !headerItem)
        return false;
 
    beginInsertColumns(parent, column, column + count - 1);
 
    int oldCount = columnCount(parent);
    column = qBound(0, column, oldCount);
    headerItem->values.resize(oldCount + count);
    for (int i = oldCount; i < oldCount + count; ++i) {
        headerItem->values[i].append(QWidgetItemData(Qt::DisplayRole, QString::number(i + 1)));
        headerItem->d->display.append(QString::number(i + 1));
    }
 
    QStack<QTreeWidgetItem*> itemstack;
    itemstack.push(0);
    while (!itemstack.isEmpty()) {
        QTreeWidgetItem *par = itemstack.pop();
        QList<QTreeWidgetItem*> children = par ? par->children : rootItem->children;
        for (int row = 0; row < children.size(); ++row) {
            QTreeWidgetItem *child = children.at(row);
            if (child->children.size())
                itemstack.push(child);
            child->values.insert(column, count, QList<QWidgetItemData>());
        }
    }
 
    endInsertColumns();
    return true;
}
 
bool QTreeModel::removeRows(int row, int count, const QModelIndex &parent) {
    if (count < 1 || row < 0 || (row + count) > rowCount(parent))
        return false;
    QTreeWidgetItem *parentItem = item(parent);
    // if parentItem is valid, begin/end RemoveRows is handled by takeChild below
    if (!parentItem)
        beginRemoveRows(parent, row, row + count - 1);
    for (int i = row + count - 1; i >= row; --i) {
        QTreeWidgetItem *child = parentItem ? parentItem->takeChild(i) : rootItem->children.takeAt(i);
        Q_ASSERT(child);
        child->view = nullptr;
        delete child;
    }
    if (!parentItem)
        endRemoveRows();
    return true;
}
 
QVariant QTreeModel::headerData(int section, Qt::Orientation orientation, int role) const
{
    if (orientation != Qt::Horizontal)
        return QVariant();
 
    if (headerItem)
        return headerItem->data(section, role);
    if (role == Qt::DisplayRole)
        return QString::number(section + 1);
    return QVariant();
}
 
bool QTreeModel::setHeaderData(int section, Qt::Orientation orientation,
                               const QVariant &value, int role)
{
    if (section < 0 || orientation != Qt::Horizontal || !headerItem || section >= columnCount())
        return false;
 
    headerItem->setData(section, role, value);
    return true;
}
 
Qt::ItemFlags QTreeModel::flags(const QModelIndex &index) const
{
    if (!index.isValid())
        return rootItem->flags();
    QTreeWidgetItem *itm = item(index);
    Q_ASSERT(itm);
    return itm->flags();
}
 
void QTreeModel::sort(int column, Qt::SortOrder order)
{
    SkipSorting skipSorting(this);
    sortPendingTimer.stop();
 
    if (column < 0 || column >= columnCount())
        return;
 
    //layoutAboutToBeChanged and layoutChanged will be called by sortChildren
    rootItem->sortChildren(column, order, true);
}
 
void QTreeModel::ensureSorted(int column, Qt::SortOrder order,
                              int start, int end, const QModelIndex &parent)
{
    if (isChanging())
        return;
 
    sortPendingTimer.stop();
 
    if (column < 0 || column >= columnCount())
        return;
 
    SkipSorting skipSorting(this);
 
    QTreeWidgetItem *itm = item(parent);
    if (!itm)
        itm = rootItem;
    QList<QTreeWidgetItem*> lst = itm->children;
 
    int count = end - start + 1;
    QList<QPair<QTreeWidgetItem *, int>> sorting(count);
    for (int i = 0; i < count; ++i) {
        sorting[i].first = lst.at(start + i);
        sorting[i].second = start + i;
    }
 
    const auto compare = (order == Qt::AscendingOrder ? &itemLessThan : &itemGreaterThan);
    std::stable_sort(sorting.begin(), sorting.end(), compare);
 
    QModelIndexList oldPersistentIndexes;
    QModelIndexList newPersistentIndexes;
    QList<QTreeWidgetItem*>::iterator lit = lst.begin();
    bool changed = false;
 
    for (int i = 0; i < count; ++i) {
        int oldRow = sorting.at(i).second;
 
        int tmpitepos = lit - lst.begin();
        QTreeWidgetItem *item = lst.takeAt(oldRow);
        if (tmpitepos > lst.size())
            --tmpitepos;
        lit = lst.begin() + tmpitepos;
 
        lit = sortedInsertionIterator(lit, lst.end(), order, item);
        int newRow = qMax<qsizetype>(lit - lst.begin(), 0);
 
        if ((newRow < oldRow) && !(*item < *lst.at(oldRow - 1)) && !(*lst.at(oldRow - 1) < *item ))
            newRow = oldRow;
 
        lit = lst.insert(lit, item);
        if (newRow != oldRow) {
            // we are going to change the persistent indexes, so we need to prepare
            if (!changed) { // this will only happen once
                changed = true;
                emit layoutAboutToBeChanged({parent}, QAbstractItemModel::VerticalSortHint); // the selection model needs to know
                oldPersistentIndexes = persistentIndexList();
                newPersistentIndexes = oldPersistentIndexes;
            }
            for (int j = i + 1; j < count; ++j) {
                int otherRow = sorting.at(j).second;
                if (oldRow < otherRow && newRow >= otherRow)
                    --sorting[j].second;
                else if (oldRow > otherRow && newRow <= otherRow)
                    ++sorting[j].second;
            }
            for (int k = 0; k < newPersistentIndexes.size(); ++k) {
                QModelIndex pi = newPersistentIndexes.at(k);
                if (pi.parent() != parent)
                    continue;
                int oldPersistentRow = pi.row();
                int newPersistentRow = oldPersistentRow;
                if (oldPersistentRow == oldRow)
                    newPersistentRow = newRow;
                else if (oldRow < oldPersistentRow && newRow >= oldPersistentRow)
                    newPersistentRow = oldPersistentRow - 1;
                else if (oldRow > oldPersistentRow && newRow <= oldPersistentRow)
                    newPersistentRow = oldPersistentRow + 1;
                if (newPersistentRow != oldPersistentRow)
                    newPersistentIndexes[k] = createIndex(newPersistentRow,
                                                          pi.column(), pi.internalPointer());
            }
        }
    }
 
    if (changed) {
        itm->children = lst;
        changePersistentIndexList(oldPersistentIndexes, newPersistentIndexes);
        emit layoutChanged({parent}, QAbstractItemModel::VerticalSortHint);
    }
}
 
bool QTreeModel::itemLessThan(const QPair<QTreeWidgetItem*,int> &left,
                              const QPair<QTreeWidgetItem*,int> &right)
{
    return *(left.first) < *(right.first);
}
 
bool QTreeModel::itemGreaterThan(const QPair<QTreeWidgetItem*,int> &left,
                                 const QPair<QTreeWidgetItem*,int> &right)
{
    return *(right.first) < *(left.first);
}
 
QList<QTreeWidgetItem*>::iterator QTreeModel::sortedInsertionIterator(
    const QList<QTreeWidgetItem*>::iterator &begin,
    const QList<QTreeWidgetItem*>::iterator &end,
    Qt::SortOrder order, QTreeWidgetItem *item)
{
    if (order == Qt::AscendingOrder)
        return std::lower_bound(begin, end, item, QTreeModelLessThan());
    return std::lower_bound(begin, end, item, QTreeModelGreaterThan());
}
 
QStringList QTreeModel::mimeTypes() const
{
    auto v = view();
    if (v)
        return v->mimeTypes();
    return {};
}
 
QMimeData *QTreeModel::internalMimeData()  const
{
    return QAbstractItemModel::mimeData(cachedIndexes);
}
 
QMimeData *QTreeModel::mimeData(const QModelIndexList &indexes) const
{
    QList<QTreeWidgetItem *> items;
    std::transform(indexes.begin(), indexes.end(), std::back_inserter(items),
                   [this](const QModelIndex &idx) -> QTreeWidgetItem * { return item(idx); });
 
    // Ensure we only have one item as an item may have more than
    // one index selected if there is more than one column
    std::sort(items.begin(), items.end());
    items.erase(std::unique(items.begin(), items.end()), items.end());
 
    // cachedIndexes is a little hack to avoid copying from QModelIndexList to
    // QList<QTreeWidgetItem*> and back again in the view
    cachedIndexes = indexes;
    QMimeData *mimeData = view()->mimeData(items);
    cachedIndexes.clear();
    return mimeData;
}
 
bool QTreeModel::dropMimeData(const QMimeData *data, Qt::DropAction action,
                              int row, int column, const QModelIndex &parent)
{
    if (row == -1 && column == -1)
        row = rowCount(parent); // append
    return view()->dropMimeData(item(parent), row, data, action);
}
 
Qt::DropActions QTreeModel::supportedDropActions() const
{
    return view()->supportedDropActions();
}
 
void QTreeModel::itemChanged(QTreeWidgetItem *item)
{
    SkipSorting skipSorting(this); //this is kind of wrong, but not doing this would kill performance
    QModelIndex left = index(item, 0);
    QModelIndex right = index(item, item->columnCount() - 1);
    emit dataChanged(left, right);
}
 
bool QTreeModel::isChanging() const
{
    Q_D(const QTreeModel);
    return !d->changes.isEmpty();
}
 
void QTreeModel::emitDataChanged(QTreeWidgetItem *item, int column, const QList<int> &roles)
{
    if (signalsBlocked())
        return;
 
    if (headerItem == item && column < item->columnCount()) {
        if (column == -1)
            emit headerDataChanged(Qt::Horizontal, 0, columnCount() - 1);
        else
            emit headerDataChanged(Qt::Horizontal, column, column);
        return;
    }
 
    SkipSorting skipSorting(this); //This is a little bit wrong, but not doing it would kill performance
 
    QModelIndex bottomRight, topLeft;
    if (column == -1) {
        topLeft = index(item, 0);
        bottomRight = createIndex(topLeft.row(), columnCount() - 1, item);
    } else {
        topLeft = index(item, column);
        bottomRight = topLeft;
    }
    emit dataChanged(topLeft, bottomRight, roles);
}
 
void QTreeModel::beginInsertItems(QTreeWidgetItem *parent, int row, int count)
{
    QModelIndex par = index(parent, 0);
    beginInsertRows(par, row, row + count - 1);
}
 
void QTreeModel::endInsertItems()
{
    endInsertRows();
}
 
void QTreeModel::beginRemoveItems(QTreeWidgetItem *parent, int row, int count)
{
    Q_ASSERT(row >= 0);
    Q_ASSERT(count > 0);
    beginRemoveRows(index(parent, 0), row, row + count - 1);
    if (!parent)
        parent = rootItem;
    // now update the iterators
    for (int i = 0; i < iterators.size(); ++i) {
        for (int j = 0; j < count; j++) {
            QTreeWidgetItem *c = parent->child(row + j);
            iterators[i]->d_func()->ensureValidIterator(c);
        }
    }
}
 
void QTreeModel::endRemoveItems()
{
    endRemoveRows();
}
 
void QTreeModel::sortItems(QList<QTreeWidgetItem*> *items, int column, Qt::SortOrder order)
{
    // see QTreeViewItem::operator<
    Q_UNUSED(column);
    if (isChanging())
        return;
 
    // store the original order of indexes
    QList<QPair<QTreeWidgetItem *, int>> sorting(items->size());
    for (int i = 0; i < sorting.size(); ++i) {
        sorting[i].first = items->at(i);
        sorting[i].second = i;
    }
 
    // do the sorting
    const auto compare = (order == Qt::AscendingOrder ? &itemLessThan : &itemGreaterThan);
    std::stable_sort(sorting.begin(), sorting.end(), compare);
 
    QModelIndexList fromList;
    QModelIndexList toList;
    int colCount = columnCount();
    for (int r = 0; r < sorting.size(); ++r) {
        int oldRow = sorting.at(r).second;
        if (oldRow == r)
            continue;
        QTreeWidgetItem *item = sorting.at(r).first;
        items->replace(r, item);
        for (int c = 0; c < colCount; ++c) {
            QModelIndex from = createIndex(oldRow, c, item);
            if (static_cast<QAbstractItemModelPrivate *>(d_ptr.data())->persistent.indexes.contains(from)) {
                QModelIndex to = createIndex(r, c, item);
                fromList << from;
                toList << to;
            }
        }
    }
    changePersistentIndexList(fromList, toList);
}
 
void QTreeModel::timerEvent(QTimerEvent *ev)
{
    if (ev->timerId() == sortPendingTimer.timerId()) {
        executePendingSort();
    } else {
        QAbstractItemModel::timerEvent(ev);
    }
}
 
void QTreeWidgetItem::setSelected(bool select)
{
    const QTreeModel *model = treeModel();
    if (!model || !view->selectionModel())
        return;
    const QModelIndex index = model->index(this, 0);
    view->selectionModel()->select(index, (select ? QItemSelectionModel::Select
                                                  : QItemSelectionModel::Deselect)
                                   | QItemSelectionModel::Rows);
    d->selected = select;
}
 
bool QTreeWidgetItem::isSelected() const
{
    return d->selected;
}
 
void QTreeWidgetItem::setHidden(bool hide)
{
    const QTreeModel *model = treeModel();
    if (!model)
        return;
    if (this == model->headerItem) {
        view->header()->setHidden(hide);
    } else {
        const QModelIndex index = view->d_func()->index(this);
        view->setRowHidden(index.row(), index.parent(), hide);
    }
    d->hidden = hide;
}
 
bool QTreeWidgetItem::isHidden() const
{
    const QTreeModel *model = treeModel();
    if (!model)
        return false;
    if (this == model->headerItem)
        return view->header()->isHidden();
    if (view->d_func()->hiddenIndexes.isEmpty())
        return false;
    QTreeModel::SkipSorting skipSorting(model);
    return view->d_func()->isRowHidden(view->d_func()->index(this));
}
 
void QTreeWidgetItem::setExpanded(bool expand)
{
    const QTreeModel *model = treeModel();
    if (!model)
        return;
    QTreeModel::SkipSorting skipSorting(model);
    view->setExpanded(view->d_func()->index(this), expand);
}
 
bool QTreeWidgetItem::isExpanded() const
{
    const QTreeModel *model = treeModel();
    if (!model)
        return false;
    QTreeModel::SkipSorting skipSorting(model);
    return view->isExpanded(view->d_func()->index(this));
}
 
void QTreeWidgetItem::setFirstColumnSpanned(bool span)
{
    const QTreeModel *model = treeModel();
    if (!model || this == model->headerItem)
        return; // We can't set the header items to spanning
    const QModelIndex index = model->index(this, 0);
    view->setFirstColumnSpanned(index.row(), index.parent(), span);
}
 
bool QTreeWidgetItem::isFirstColumnSpanned() const
{
    const QTreeModel *model = treeModel();
    if (!model || this == model->headerItem)
        return false;
    const QModelIndex index = model->index(this, 0);
    return view->isFirstColumnSpanned(index.row(), index.parent());
}
 
QTreeWidgetItem::QTreeWidgetItem(int type) : rtti(type), d(new QTreeWidgetItemPrivate(this)) { }
 
QTreeWidgetItem::QTreeWidgetItem(const QStringList &strings, int type)
    : rtti(type), d(new QTreeWidgetItemPrivate(this))
{
    for (int i = 0; i < strings.size(); ++i)
        setText(i, strings.at(i));
}
 
QTreeWidgetItem::QTreeWidgetItem(QTreeWidget *treeview, int type)
    : rtti(type), d(new QTreeWidgetItemPrivate(this))
{
    // do not set this->view here otherwise insertChild() will fail
    if (QTreeModel *model = treeModel(treeview)) {
        model->rootItem->addChild(this);
        values.reserve(model->headerItem->columnCount());
    }
}
 
QTreeWidgetItem::QTreeWidgetItem(QTreeWidget *treeview, const QStringList &strings, int type)
    : rtti(type), d(new QTreeWidgetItemPrivate(this))
{
    for (int i = 0; i < strings.size(); ++i)
        setText(i, strings.at(i));
    // do not set this->view here otherwise insertChild() will fail
    if (QTreeModel *model = treeModel(treeview)) {
        model->rootItem->addChild(this);
        values.reserve(model->headerItem->columnCount());
    }
}
 
QTreeWidgetItem::QTreeWidgetItem(QTreeWidget *treeview, QTreeWidgetItem *after, int type)
    : rtti(type), d(new QTreeWidgetItemPrivate(this))
{
    // do not set this->view here otherwise insertChild() will fail
    if (QTreeModel *model = treeModel(treeview)) {
        int i = model->rootItem->children.indexOf(after) + 1;
        model->rootItem->insertChild(i, this);
        values.reserve(model->headerItem->columnCount());
    }
}
 
QTreeWidgetItem::QTreeWidgetItem(QTreeWidgetItem *parent, int type)
    : rtti(type), d(new QTreeWidgetItemPrivate(this))
{
    if (parent)
        parent->addChild(this);
}
 
QTreeWidgetItem::QTreeWidgetItem(QTreeWidgetItem *parent, const QStringList &strings, int type)
    : rtti(type), d(new QTreeWidgetItemPrivate(this))
{
    for (int i = 0; i < strings.size(); ++i)
        setText(i, strings.at(i));
    if (parent)
        parent->addChild(this);
}
 
QTreeWidgetItem::QTreeWidgetItem(QTreeWidgetItem *parent, QTreeWidgetItem *after, int type)
    : rtti(type), d(new QTreeWidgetItemPrivate(this))
{
    if (parent) {
        int i = parent->children.indexOf(after) + 1;
        parent->insertChild(i, this);
    }
}
 
QTreeWidgetItem::~QTreeWidgetItem()
{
    QTreeModel *model = treeModel();
    QTreeModel::SkipSorting skipSorting(model);
 
    if (par) {
        int i = par->children.indexOf(this);
        if (i >= 0) {
            if (model) model->beginRemoveItems(par, i, 1);
            // users _could_ do changes when connected to rowsAboutToBeRemoved,
            // so we check again to make sure 'i' is valid
            if (!par->children.isEmpty() && par->children.at(i) == this)
                par->children.takeAt(i);
            if (model) model->endRemoveItems();
        }
    } else if (model) {
        if (this == model->headerItem) {
            model->headerItem = nullptr;
        } else {
            int i = model->rootItem->children.indexOf(this);
            if (i >= 0) {
                model->beginRemoveItems(nullptr, i, 1);
                // users _could_ do changes when connected to rowsAboutToBeRemoved,
                // so we check again to make sure 'i' is valid
                if (!model->rootItem->children.isEmpty() && model->rootItem->children.at(i) == this)
                    model->rootItem->children.takeAt(i);
                model->endRemoveItems();
            }
        }
    }
    // at this point the persistent indexes for the children should also be invalidated
    // since we invalidated the parent
    for (int i = 0; i < children.size(); ++i) {
        QTreeWidgetItem *child = children.at(i);
        // make sure the child does not try to remove itself from our children list
        child->par = nullptr;
        // make sure the child does not try to remove itself from the top level list
        child->view = nullptr;
        delete child;
    }
 
    children.clear();
    delete d;
}
 
QTreeWidgetItem *QTreeWidgetItem::clone() const
{
    QTreeWidgetItem *copy = nullptr;
 
    QStack<const QTreeWidgetItem*> stack;
    QStack<QTreeWidgetItem*> parentStack;
    stack.push(this);
    parentStack.push(0);
 
    QTreeWidgetItem *root = nullptr;
    const QTreeWidgetItem *item = nullptr;
    QTreeWidgetItem *parent = nullptr;
    while (!stack.isEmpty()) {
        // get current item, and copied parent
        item = stack.pop();
        parent = parentStack.pop();
 
        // copy item
        copy = new QTreeWidgetItem(*item);
        if (!root)
            root = copy;
 
        // set parent and add to parents children list
        if (parent) {
            copy->par = parent;
            parent->children.insert(0, copy);
        }
 
        for (int i = 0; i < item->childCount(); ++i) {
            stack.push(item->child(i));
            parentStack.push(copy);
        }
    }
    return root;
}
 
void QTreeWidgetItem::setChildIndicatorPolicy(QTreeWidgetItem::ChildIndicatorPolicy policy)
{
    if (d->policy == policy)
        return;
    d->policy = policy;
 
    if (!view)
        return;
 
    view->scheduleDelayedItemsLayout();
}
 
QTreeWidgetItem::ChildIndicatorPolicy QTreeWidgetItem::childIndicatorPolicy() const
{
    return d->policy;
}
 
void QTreeWidgetItem::setFlags(Qt::ItemFlags flags)
{
    const bool enable = (flags & Qt::ItemIsEnabled);
    const bool changedState = bool(itemFlags & Qt::ItemIsEnabled) != enable;
    const bool changedExplicit = d->disabled != !enable;
 
    d->disabled = !enable;
 
    if (enable && par && !(par->itemFlags & Qt::ItemIsEnabled)) // inherit from parent
        itemFlags = flags & ~Qt::ItemIsEnabled;
    else // this item is explicitly disabled or has no parent
        itemFlags = flags;
 
    if (changedState && changedExplicit) { // if the propagate the change to the children
        QStack<QTreeWidgetItem*> parents;
        parents.push(this);
        while (!parents.isEmpty()) {
            QTreeWidgetItem *parent = parents.pop();
            for (int i = 0; i < parent->children.size(); ++i) {
                QTreeWidgetItem *child = parent->children.at(i);
                if (!child->d->disabled) { // if not explicitly disabled
                    parents.push(child);
                    if (enable)
                        child->itemFlags = child->itemFlags | Qt::ItemIsEnabled;
                    else
                        child->itemFlags = child->itemFlags & ~Qt::ItemIsEnabled;
                    child->itemChanged(); // ### we may want to optimize this
                }
            }
        }
    }
    itemChanged();
}
 
void QTreeWidgetItemPrivate::updateHiddenStatus(QTreeWidgetItem *item, bool inserting)
{
    QTreeModel *model = item->treeModel();
    if (!model)
        return;
    QStack<QTreeWidgetItem *> parents;
    parents.push(item);
    while (!parents.isEmpty()) {
        QTreeWidgetItem *parent = parents.pop();
        if (parent->d->hidden) {
            const QModelIndex index = model->index(parent, 0);
            item->view->setRowHidden(index.row(), index.parent(), inserting);
        }
        for (int i = 0; i < parent->children.size(); ++i) {
            QTreeWidgetItem *child = parent->children.at(i);
            parents.push(child);
        }
    }
}
 
void QTreeWidgetItemPrivate::propagateDisabled(QTreeWidgetItem *item)
{
    Q_ASSERT(item);
    const bool enable = item->par ? (item->par->itemFlags.testFlag(Qt::ItemIsEnabled)) : true;
 
    QStack<QTreeWidgetItem*> parents;
    parents.push(item);
    while (!parents.isEmpty()) {
        QTreeWidgetItem *parent = parents.pop();
        if (!parent->d->disabled) { // if not explicitly disabled
            Qt::ItemFlags oldFlags = parent->itemFlags;
            if (enable)
                parent->itemFlags = parent->itemFlags | Qt::ItemIsEnabled;
            else
                parent->itemFlags = parent->itemFlags & ~Qt::ItemIsEnabled;
            if (parent->itemFlags != oldFlags)
                parent->itemChanged();
        }
 
        for (int i = 0; i < parent->children.size(); ++i) {
            QTreeWidgetItem *child = parent->children.at(i);
            parents.push(child);
        }
    }
}
Qt::ItemFlags QTreeWidgetItem::flags() const
{
    return itemFlags;
}
 
void QTreeWidgetItem::setData(int column, int role, const QVariant &value)
{
    if (column < 0)
        return;
 
    QTreeModel *model = treeModel();
    switch (role) {
    case Qt::EditRole:
    case Qt::DisplayRole: {
        if (values.size() <= column) {
            if (model && this == model->headerItem)
                model->setColumnCount(column + 1);
            else
                values.resize(column + 1);
        }
        if (d->display.size() <= column) {
            for (int i = d->display.size() - 1; i < column - 1; ++i)
                d->display.append(QVariant());
            d->display.append(value);
        } else if (d->display[column] != value) {
            d->display[column] = value;
        } else {
            return; // value is unchanged
        }
    } break;
    case Qt::CheckStateRole:
        if ((itemFlags & Qt::ItemIsAutoTristate) && value != Qt::PartiallyChecked) {
            for (int i = 0; i < children.size(); ++i) {
                QTreeWidgetItem *child = children.at(i);
                if (child->data(column, role).isValid()) {// has a CheckState
                    Qt::ItemFlags f = itemFlags; // a little hack to avoid multiple dataChanged signals
                    itemFlags &= ~Qt::ItemIsAutoTristate;
                    child->setData(column, role, value);
                    itemFlags = f;
                }
            }
        }
        Q_FALLTHROUGH();
    default:
        if (column < values.size()) {
            bool found = false;
            const QList<QWidgetItemData> column_values = values.at(column);
            for (int i = 0; i < column_values.size(); ++i) {
                if (column_values.at(i).role == role) {
                    if (column_values.at(i).value == value)
                        return; // value is unchanged
                    values[column][i].value = value;
                    found = true;
                    break;
                }
            }
            if (!found)
                values[column].append(QWidgetItemData(role, value));
        } else {
            if (model && this == model->headerItem)
                model->setColumnCount(column + 1);
            else
                values.resize(column + 1);
            values[column].append(QWidgetItemData(role, value));
        }
    }
 
    if (model) {
        const QList<int> roles((role == Qt::DisplayRole || role == Qt::EditRole)
                                       ? QList<int>({ Qt::DisplayRole, Qt::EditRole })
                                       : QList<int>({ role }));
        model->emitDataChanged(this, column, roles);
        if (role == Qt::CheckStateRole) {
            QTreeWidgetItem *p;
            for (p = par; p && (p->itemFlags & Qt::ItemIsAutoTristate); p = p->par)
                model->emitDataChanged(p, column, roles);
        }
    }
}
 
QVariant QTreeWidgetItem::data(int column, int role) const
{
    switch (role) {
    case Qt::EditRole:
    case Qt::DisplayRole:
        if (column >= 0 && column < d->display.size())
            return d->display.at(column);
        break;
    case Qt::CheckStateRole:
        // special case for check state in tristate
        if (children.size() && (itemFlags & Qt::ItemIsAutoTristate))
            return childrenCheckState(column);
        Q_FALLTHROUGH();
   default:
        if (column >= 0 && column < values.size()) {
            const QList<QWidgetItemData> &column_values = values.at(column);
            for (const auto &column_value : column_values) {
                if (column_value.role == role)
                    return column_value.value;
            }
        }
    }
    return QVariant();
}
 
bool QTreeWidgetItem::operator<(const QTreeWidgetItem &other) const
{
    int column = view ? view->sortColumn() : 0;
    const QVariant v1 = data(column, Qt::DisplayRole);
    const QVariant v2 = other.data(column, Qt::DisplayRole);
    return QAbstractItemModelPrivate::variantLessThan(v1, v2);
}
 
#ifndef QT_NO_DATASTREAM
 
void QTreeWidgetItem::read(QDataStream &in)
{
    // convert from streams written before we introduced display (4.2.0)
    if (in.version() < QDataStream::Qt_4_2) {
        d->display.clear();
        in >> values;
        // move the display value over to the display string list
        for (int column = 0; column < values.size(); ++column) {
            d->display << QVariant();
            for (int i = 0; i < values.at(column).size(); ++i) {
                if (values.at(column).at(i).role == Qt::DisplayRole) {
                    d->display[column] = values.at(column).at(i).value;
                    values[column].remove(i--);
                }
            }
        }
    } else {
        in >> values >> d->display;
    }
}
 
void QTreeWidgetItem::write(QDataStream &out) const
{
    out << values << d->display;
}
#endif // QT_NO_DATASTREAM
 
QTreeWidgetItem::QTreeWidgetItem(const QTreeWidgetItem &other)
    : rtti(Type),
      values(other.values),
      d(new QTreeWidgetItemPrivate(this)),
      itemFlags(other.itemFlags)
{
    d->display = other.d->display;
}
 
QTreeWidgetItem &QTreeWidgetItem::operator=(const QTreeWidgetItem &other)
{
    values = other.values;
    d->display = other.d->display;
    d->policy = other.d->policy;
    itemFlags = other.itemFlags;
    return *this;
}
 
void QTreeWidgetItem::addChild(QTreeWidgetItem *child)
{
    if (child) {
        insertChild(children.size(), child);
        child->d->rowGuess = children.size() - 1;
    }
}
 
void QTreeWidgetItem::insertChild(int index, QTreeWidgetItem *child)
{
    if (index < 0 || index > children.size() || child == nullptr || child->view != nullptr || child->par != nullptr)
        return;
 
    if (QTreeModel *model = treeModel()) {
        QTreeModel::SkipSorting skipSorting(model);
        if (model->rootItem == this)
            child->par = nullptr;
        else
            child->par = this;
        if (view->isSortingEnabled()) {
            // do a delayed sort instead
            if (!model->sortPendingTimer.isActive())
                model->sortPendingTimer.start(0, model);
        }
        model->beginInsertItems(this, index, 1);
        int cols = model->columnCount();
        QStack<QTreeWidgetItem*> stack;
        stack.push(child);
        while (!stack.isEmpty()) {
            QTreeWidgetItem *i = stack.pop();
            i->view = view;
            i->values.reserve(cols);
            for (int c = 0; c < i->children.size(); ++c)
                stack.push(i->children.at(c));
        }
        children.insert(index, child);
        d->updateHiddenStatus(child, true);
        model->endInsertItems();
    } else {
        child->par = this;
        children.insert(index, child);
    }
    if (child->par)
        d->propagateDisabled(child);
}
 
void QTreeWidgetItem::removeChild(QTreeWidgetItem *child)
{
    (void)takeChild(children.indexOf(child));
}
 
QTreeWidgetItem *QTreeWidgetItem::takeChild(int index)
{
    // we move this outside the check of the index to allow executing
    // pending sorts from inline functions, using this function (hack)
    QTreeModel *model = treeModel();
    if (model) {
        // This will trigger a layoutChanged signal, thus we might want to optimize
        // this function by not emitting the rowsRemoved signal etc to the view.
        // On the other hand we also need to make sure that the selectionmodel
        // is updated in case we take an item that is selected.
        model->skipPendingSort = false;
        model->executePendingSort();
    }
    if (index >= 0 && index < children.size()) {
        if (model) model->beginRemoveItems(this, index, 1);
        d->updateHiddenStatus(children.at(index), false);
        QTreeWidgetItem *item = children.takeAt(index);
        item->par = nullptr;
        QStack<QTreeWidgetItem*> stack;
        stack.push(item);
        while (!stack.isEmpty()) {
            QTreeWidgetItem *i = stack.pop();
            i->view = nullptr;
            for (int c = 0; c < i->children.size(); ++c)
                stack.push(i->children.at(c));
        }
        d->propagateDisabled(item);
        if (model) model->endRemoveRows();
        return item;
    }
    return nullptr;
}
 
void QTreeWidgetItem::addChildren(const QList<QTreeWidgetItem*> &children)
{
    insertChildren(this->children.size(), children);
}
 
void QTreeWidgetItem::insertChildren(int index, const QList<QTreeWidgetItem*> &children)
{
    if (index < 0 || index > this->children.size() || children.isEmpty())
        return;
 
    if (view && view->isSortingEnabled()) {
        for (int n = 0; n < children.size(); ++n)
            insertChild(index, children.at(n));
        return;
    }
    QTreeModel *model = treeModel();
    QStack<QTreeWidgetItem*> stack;
    QList<QTreeWidgetItem*> itemsToInsert;
    for (int n = 0; n < children.size(); ++n) {
        QTreeWidgetItem *child = children.at(n);
        if (child->view || child->par)
            continue;
        itemsToInsert.append(child);
        if (view && model) {
            if (child->childCount() == 0)
                child->view = view;
            else
                stack.push(child);
        }
        if (model && (model->rootItem == this))
            child->par = nullptr;
        else
            child->par = this;
    }
    if (!itemsToInsert.isEmpty()) {
        while (!stack.isEmpty()) {
            QTreeWidgetItem *i = stack.pop();
            i->view = view;
            for (int c = 0; c < i->children.size(); ++c)
                stack.push(i->children.at(c));
        }
        if (model) model->beginInsertItems(this, index, itemsToInsert.size());
        for (int n = 0; n < itemsToInsert.size(); ++n) {
            QTreeWidgetItem *child = itemsToInsert.at(n);
            this->children.insert(index + n, child);
            if (child->par)
                d->propagateDisabled(child);
            d->updateHiddenStatus(child, true);
        }
        if (model) model->endInsertItems();
    }
}
 
QList<QTreeWidgetItem*> QTreeWidgetItem::takeChildren()
{
    QList<QTreeWidgetItem*> removed;
    if (children.size() > 0) {
        QTreeModel *model = treeModel();
        if (model) {
            // This will trigger a layoutChanged signal, thus we might want to optimize
            // this function by not emitting the rowsRemoved signal etc to the view.
            // On the other hand we also need to make sure that the selectionmodel
            // is updated in case we take an item that is selected.
            model->executePendingSort();
        }
        if (model) model->beginRemoveItems(this, 0, children.size());
        for (int n = 0; n < children.size(); ++n) {
            QTreeWidgetItem *item = children.at(n);
            item->par = nullptr;
            QStack<QTreeWidgetItem*> stack;
            stack.push(item);
            while (!stack.isEmpty()) {
                QTreeWidgetItem *i = stack.pop();
                i->view = nullptr;
                for (int c = 0; c < i->children.size(); ++c)
                    stack.push(i->children.at(c));
            }
            d->propagateDisabled(item);
        }
        removed = children;
        children.clear(); // detach
        if (model) model->endRemoveItems();
    }
    return removed;
}
 
 
void QTreeWidgetItemPrivate::sortChildren(int column, Qt::SortOrder order, bool climb)
{
    QTreeModel *model = q->treeModel();
    if (!model)
        return;
    model->sortItems(&q->children, column, order);
    if (climb) {
        QList<QTreeWidgetItem*>::iterator it = q->children.begin();
        for (; it != q->children.end(); ++it) {
            //here we call the private object's method to avoid emitting
            //the layoutAboutToBeChanged and layoutChanged signals
            (*it)->d->sortChildren(column, order, climb);
        }
    }
}
 
void QTreeWidgetItem::sortChildren(int column, Qt::SortOrder order, bool climb)
{
    QTreeModel *model = treeModel();
    if (!model)
        return;
    if (model->isChanging())
        return;
    QTreeModel::SkipSorting skipSorting(model);
    int oldSortColumn = view->d_func()->explicitSortColumn;
    view->d_func()->explicitSortColumn = column;
    emit model->layoutAboutToBeChanged({}, QAbstractItemModel::VerticalSortHint);
    d->sortChildren(column, order, climb);
    emit model->layoutChanged({}, QAbstractItemModel::VerticalSortHint);
    view->d_func()->explicitSortColumn = oldSortColumn;
}
 
QVariant QTreeWidgetItem::childrenCheckState(int column) const
{
    if (column < 0)
        return QVariant();
    bool checkedChildren = false;
    bool uncheckedChildren = false;
    for (const auto *child : children) {
        QVariant value = child->data(column, Qt::CheckStateRole);
        if (!value.isValid())
            return QVariant();
 
        switch (static_cast<Qt::CheckState>(value.toInt()))
        {
        case Qt::Unchecked:
            uncheckedChildren = true;
            break;
        case Qt::Checked:
            checkedChildren = true;
            break;
        case Qt::PartiallyChecked:
        default:
            return Qt::PartiallyChecked;
        }
 
        if (uncheckedChildren && checkedChildren)
            return Qt::PartiallyChecked;
    }
 
    if (uncheckedChildren)
        return Qt::Unchecked;
    else if (checkedChildren)
        return Qt::Checked;
    else
        return QVariant(); // value was not defined
}
 
void QTreeWidgetItem::emitDataChanged()
{
    itemChanged();
}
 
void QTreeWidgetItem::itemChanged()
{
    if (QTreeModel *model = treeModel())
        model->itemChanged(this);
}
 
void QTreeWidgetItem::executePendingSort() const
{
    if (QTreeModel *model = treeModel())
        model->executePendingSort();
}
 
QTreeModel *QTreeWidgetItem::treeModel(QTreeWidget *v) const
{
    if (!v)
        v = view;
    return (v ? qobject_cast<QTreeModel*>(v->model()) : nullptr);
}
 
 
#ifndef QT_NO_DATASTREAM
QDataStream &operator<<(QDataStream &out, const QTreeWidgetItem &item)
{
    item.write(out);
    return out;
}
 
QDataStream &operator>>(QDataStream &in, QTreeWidgetItem &item)
{
    item.read(in);
    return in;
}
#endif // QT_NO_DATASTREAM
 
 
void QTreeWidgetPrivate::_q_emitItemPressed(const QModelIndex &index)
{
    Q_Q(QTreeWidget);
    emit q->itemPressed(item(index), index.column());
}
 
void QTreeWidgetPrivate::_q_emitItemClicked(const QModelIndex &index)
{
    Q_Q(QTreeWidget);
    emit q->itemClicked(item(index), index.column());
}
 
void QTreeWidgetPrivate::_q_emitItemDoubleClicked(const QModelIndex &index)
{
    Q_Q(QTreeWidget);
    emit q->itemDoubleClicked(item(index), index.column());
}
 
void QTreeWidgetPrivate::_q_emitItemActivated(const QModelIndex &index)
{
    Q_Q(QTreeWidget);
    emit q->itemActivated(item(index), index.column());
}
 
void QTreeWidgetPrivate::_q_emitItemEntered(const QModelIndex &index)
{
    Q_Q(QTreeWidget);
    emit q->itemEntered(item(index), index.column());
}
 
void QTreeWidgetPrivate::_q_emitItemChanged(const QModelIndex &index)
{
    Q_Q(QTreeWidget);
    QTreeWidgetItem *indexItem = item(index);
    if (indexItem)
        emit q->itemChanged(indexItem, index.column());
}
 
void QTreeWidgetPrivate::_q_emitItemExpanded(const QModelIndex &index)
{
    Q_Q(QTreeWidget);
    emit q->itemExpanded(item(index));
}
 
void QTreeWidgetPrivate::_q_emitItemCollapsed(const QModelIndex &index)
{
    Q_Q(QTreeWidget);
    emit q->itemCollapsed(item(index));
}
 
void QTreeWidgetPrivate::_q_emitCurrentItemChanged(const QModelIndex &current,
                                                const QModelIndex &previous)
{
    Q_Q(QTreeWidget);
    QTreeWidgetItem *currentItem = item(current);
    QTreeWidgetItem *previousItem = item(previous);
    emit q->currentItemChanged(currentItem, previousItem);
}
 
void QTreeWidgetPrivate::_q_sort()
{
    if (sortingEnabled) {
        int column = header->sortIndicatorSection();
        Qt::SortOrder order = header->sortIndicatorOrder();
        treeModel()->sort(column, order);
    }
}
 
void QTreeWidgetPrivate::_q_selectionChanged(const QItemSelection &selected, const QItemSelection &deselected)
{
    Q_Q(QTreeWidget);
    QModelIndexList indices = selected.indexes();
    int i;
    QTreeModel *m = treeModel();
    for (i = 0; i < indices.size(); ++i) {
        QTreeWidgetItem *item = m->item(indices.at(i));
        item->d->selected = true;
    }
 
    indices = deselected.indexes();
    for (i = 0; i < indices.size(); ++i) {
        QTreeWidgetItem *item = m->item(indices.at(i));
        item->d->selected = false;
    }
 
    emit q->itemSelectionChanged();
}
 
void QTreeWidgetPrivate::_q_dataChanged(const QModelIndex &topLeft,
                                        const QModelIndex &bottomRight)
{
    if (sortingEnabled && topLeft.isValid() && bottomRight.isValid()
        && !treeModel()->sortPendingTimer.isActive()) {
        int column = header->sortIndicatorSection();
        if (column >= topLeft.column() && column <= bottomRight.column()) {
            Qt::SortOrder order = header->sortIndicatorOrder();
            treeModel()->ensureSorted(column, order, topLeft.row(),
                                  bottomRight.row(), topLeft.parent());
        }
    }
}
 
QTreeWidget::QTreeWidget(QWidget *parent)
    : QTreeView(*new QTreeWidgetPrivate(), parent)
{
    QTreeView::setModel(new QTreeModel(1, this));
    connect(this, SIGNAL(pressed(QModelIndex)),
            SLOT(_q_emitItemPressed(QModelIndex)));
    connect(this, SIGNAL(clicked(QModelIndex)),
            SLOT(_q_emitItemClicked(QModelIndex)));
    connect(this, SIGNAL(doubleClicked(QModelIndex)),
            SLOT(_q_emitItemDoubleClicked(QModelIndex)));
    connect(this, SIGNAL(activated(QModelIndex)),
            SLOT(_q_emitItemActivated(QModelIndex)));
    connect(this, SIGNAL(entered(QModelIndex)),
            SLOT(_q_emitItemEntered(QModelIndex)));
    connect(this, SIGNAL(expanded(QModelIndex)),
            SLOT(_q_emitItemExpanded(QModelIndex)));
    connect(this, SIGNAL(collapsed(QModelIndex)),
            SLOT(_q_emitItemCollapsed(QModelIndex)));
    connect(selectionModel(), SIGNAL(currentChanged(QModelIndex,QModelIndex)),
            this, SLOT(_q_emitCurrentItemChanged(QModelIndex,QModelIndex)));
    connect(model(), SIGNAL(dataChanged(QModelIndex,QModelIndex)),
            this, SLOT(_q_emitItemChanged(QModelIndex)));
    connect(model(), SIGNAL(dataChanged(QModelIndex,QModelIndex)),
            this, SLOT(_q_dataChanged(QModelIndex,QModelIndex)));
    connect(model(), SIGNAL(columnsRemoved(QModelIndex,int,int)),
            this, SLOT(_q_sort()));
    connect(selectionModel(), SIGNAL(selectionChanged(QItemSelection,QItemSelection)),
            this, SLOT(_q_selectionChanged(QItemSelection,QItemSelection)));
    header()->setSectionsClickable(false);
}
 
QTreeWidget::~QTreeWidget()
{
}
 
/*
  Returns the number of header columns in the view.
 
  \sa sortColumn(), currentColumn(), topLevelItemCount()
*/
 
int QTreeWidget::columnCount() const
{
    Q_D(const QTreeWidget);
    return d->model->columnCount();
}
 
/*
  Sets the number of header \a columns in the tree widget.
*/
 
void QTreeWidget::setColumnCount(int columns)
{
    Q_D(QTreeWidget);
    if (columns < 0)
        return;
    d->treeModel()->setColumnCount(columns);
}
 
QTreeWidgetItem *QTreeWidget::invisibleRootItem() const
{
    Q_D(const QTreeWidget);
    return d->treeModel()->rootItem;
}
 
QTreeWidgetItem *QTreeWidget::topLevelItem(int index) const
{
    Q_D(const QTreeWidget);
    return d->treeModel()->rootItem->child(index);
}
 
int QTreeWidget::topLevelItemCount() const
{
    Q_D(const QTreeWidget);
    return d->treeModel()->rootItem->childCount();
}
 
void QTreeWidget::insertTopLevelItem(int index, QTreeWidgetItem *item)
{
    Q_D(QTreeWidget);
    d->treeModel()->rootItem->insertChild(index, item);
}
 
void QTreeWidget::addTopLevelItem(QTreeWidgetItem *item)
{
    insertTopLevelItem(topLevelItemCount(), item);
}
 
QTreeWidgetItem *QTreeWidget::takeTopLevelItem(int index)
{
    Q_D(QTreeWidget);
    return d->treeModel()->rootItem->takeChild(index);
}
 
int QTreeWidget::indexOfTopLevelItem(QTreeWidgetItem *item) const
{
    Q_D(const QTreeWidget);
    d->treeModel()->executePendingSort();
    return d->treeModel()->rootItem->children.indexOf(item);
}
 
void QTreeWidget::insertTopLevelItems(int index, const QList<QTreeWidgetItem*> &items)
{
    Q_D(QTreeWidget);
    d->treeModel()->rootItem->insertChildren(index, items);
}
 
void QTreeWidget::addTopLevelItems(const QList<QTreeWidgetItem*> &items)
{
    insertTopLevelItems(topLevelItemCount(), items);
}
 
QTreeWidgetItem *QTreeWidget::headerItem() const
{
    Q_D(const QTreeWidget);
    return d->treeModel()->headerItem;
}
 
void QTreeWidget::setHeaderItem(QTreeWidgetItem *item)
{
    Q_D(QTreeWidget);
    if (!item)
        return;
    item->view = this;
 
    int oldCount = columnCount();
    if (oldCount < item->columnCount())
         d->treeModel()->beginInsertColumns(QModelIndex(), oldCount, item->columnCount() - 1);
    else if (oldCount > item->columnCount())
         d->treeModel()->beginRemoveColumns(QModelIndex(), item->columnCount(), oldCount - 1);
    delete d->treeModel()->headerItem;
    d->treeModel()->headerItem = item;
    if (oldCount < item->columnCount())
        d->treeModel()->endInsertColumns();
    else if (oldCount > item->columnCount())
        d->treeModel()->endRemoveColumns();
    d->treeModel()->headerDataChanged(Qt::Horizontal, 0, oldCount);
}
 
 
void QTreeWidget::setHeaderLabels(const QStringList &labels)
{
    Q_D(QTreeWidget);
    if (columnCount() < labels.size())
        setColumnCount(labels.size());
    QTreeWidgetItem *item = d->treeModel()->headerItem;
    for (int i = 0; i < labels.size(); ++i)
        item->setText(i, labels.at(i));
}
 
QTreeWidgetItem *QTreeWidget::currentItem() const
{
    Q_D(const QTreeWidget);
    return d->item(currentIndex());
}
 
int QTreeWidget::currentColumn() const
{
    return currentIndex().column();
}
 
void QTreeWidget::setCurrentItem(QTreeWidgetItem *item)
{
    setCurrentItem(item, 0);
}
 
void QTreeWidget::setCurrentItem(QTreeWidgetItem *item, int column)
{
    Q_D(QTreeWidget);
    setCurrentIndex(d->index(item, column));
}
 
void QTreeWidget::setCurrentItem(QTreeWidgetItem *item, int column,
                                 QItemSelectionModel::SelectionFlags command)
{
    Q_D(QTreeWidget);
    d->selectionModel->setCurrentIndex(d->index(item, column), command);
}
 
 
QTreeWidgetItem *QTreeWidget::itemAt(const QPoint &p) const
{
    Q_D(const QTreeWidget);
    return d->item(indexAt(p));
}
 
QRect QTreeWidget::visualItemRect(const QTreeWidgetItem *item) const
{
    Q_D(const QTreeWidget);
    //the visual rect for an item is across all columns. So we need to determine
    //what is the first and last column and get their visual index rects
    const QModelIndex base = d->index(item);
    const int firstVisiblesection = header()->logicalIndexAt(- header()->offset());
    const int lastVisibleSection = header()->logicalIndexAt(header()->length() - header()->offset() - 1);
    const QModelIndex first = base.sibling(base.row(), firstVisiblesection);
    const QModelIndex last = base.sibling(base.row(), lastVisibleSection);
    return visualRect(first) | visualRect(last);
}
 
int QTreeWidget::sortColumn() const
{
    Q_D(const QTreeWidget);
    return (d->explicitSortColumn != -1
            ? d->explicitSortColumn
            : header()->sortIndicatorSection());
}
 
void QTreeWidget::sortItems(int column, Qt::SortOrder order)
{
    Q_D(QTreeWidget);
    header()->setSortIndicator(column, order);
    d->model->sort(column, order);
}
 
void QTreeWidget::editItem(QTreeWidgetItem *item, int column)
{
    Q_D(QTreeWidget);
    edit(d->index(item, column));
}
 
void QTreeWidget::openPersistentEditor(QTreeWidgetItem *item, int column)
{
    Q_D(QTreeWidget);
    QAbstractItemView::openPersistentEditor(d->index(item, column));
}
 
void QTreeWidget::closePersistentEditor(QTreeWidgetItem *item, int column)
{
    Q_D(QTreeWidget);
    QAbstractItemView::closePersistentEditor(d->index(item, column));
}
 
bool QTreeWidget::isPersistentEditorOpen(QTreeWidgetItem *item, int column) const
{
    Q_D(const QTreeWidget);
    return QAbstractItemView::isPersistentEditorOpen(d->index(item, column));
}
 
QWidget *QTreeWidget::itemWidget(QTreeWidgetItem *item, int column) const
{
    Q_D(const QTreeWidget);
    return QAbstractItemView::indexWidget(d->index(item, column));
}
 
void QTreeWidget::setItemWidget(QTreeWidgetItem *item, int column, QWidget *widget)
{
    Q_D(QTreeWidget);
    QAbstractItemView::setIndexWidget(d->index(item, column), widget);
}
 
QList<QTreeWidgetItem*> QTreeWidget::selectedItems() const
{
    Q_D(const QTreeWidget);
    const QModelIndexList indexes = selectionModel()->selectedIndexes();
    QList<QTreeWidgetItem*> items;
    items.reserve(indexes.size());
    QDuplicateTracker<QTreeWidgetItem *> seen(indexes.size());
    for (const auto &index : indexes) {
        QTreeWidgetItem *item = d->item(index);
        if (item->isHidden() || seen.hasSeen(item))
            continue;
        items.append(item);
    }
    return items;
}
 
QList<QTreeWidgetItem*> QTreeWidget::findItems(const QString &text, Qt::MatchFlags flags, int column) const
{
    Q_D(const QTreeWidget);
    QModelIndexList indexes = d->model->match(model()->index(0, column, QModelIndex()),
                                                Qt::DisplayRole, text, -1, flags);
    QList<QTreeWidgetItem*> items;
    const int indexesSize = indexes.size();
    items.reserve(indexesSize);
    for (int i = 0; i < indexesSize; ++i)
        items.append(d->item(indexes.at(i)));
    return items;
}
 
 
QTreeWidgetItem *QTreeWidget::itemAbove(const QTreeWidgetItem *item) const
{
    Q_D(const QTreeWidget);
    if (item == d->treeModel()->headerItem)
        return nullptr;
    const QModelIndex index = d->index(item);
    const QModelIndex above = indexAbove(index);
    return d->item(above);
}
 
QTreeWidgetItem *QTreeWidget::itemBelow(const QTreeWidgetItem *item) const
{
    Q_D(const QTreeWidget);
    if (item == d->treeModel()->headerItem)
        return nullptr;
    const QModelIndex index = d->index(item);
    const QModelIndex below = indexBelow(index);
    return d->item(below);
}
 
void QTreeWidget::setSelectionModel(QItemSelectionModel *selectionModel)
{
    Q_D(QTreeWidget);
    QTreeView::setSelectionModel(selectionModel);
    QItemSelection newSelection = selectionModel->selection();
    if (!newSelection.isEmpty())
        d->_q_selectionChanged(newSelection, QItemSelection());
}
 
void QTreeWidget::scrollToItem(const QTreeWidgetItem *item, QAbstractItemView::ScrollHint hint)
{
    Q_D(QTreeWidget);
    QTreeView::scrollTo(d->index(item), hint);
}
 
void QTreeWidget::expandItem(const QTreeWidgetItem *item)
{
    Q_D(QTreeWidget);
    QTreeModel::SkipSorting skipSorting(d->treeModel());
    expand(d->index(item));
}
 
void QTreeWidget::collapseItem(const QTreeWidgetItem *item)
{
    Q_D(QTreeWidget);
    QTreeModel::SkipSorting skipSorting(d->treeModel());
    collapse(d->index(item));
}
 
void QTreeWidget::clear()
{
    Q_D(QTreeWidget);
    selectionModel()->clear();
    d->treeModel()->clear();
}
 
QStringList QTreeWidget::mimeTypes() const
{
    return model()->QAbstractItemModel::mimeTypes();
}
 
QMimeData *QTreeWidget::mimeData(const QList<QTreeWidgetItem *> &items) const
{
    Q_D(const QTreeWidget);
    if (d->treeModel()->cachedIndexes.isEmpty()) {
        QList<QModelIndex> indexes;
        for (const auto *item : items) {
            if (Q_UNLIKELY(!item)) {
                qWarning("QTreeWidget::mimeData: Null-item passed");
                return nullptr;
            }
 
            for (int c = 0; c < item->values.size(); ++c) {
                const QModelIndex index = indexFromItem(item, c);
                if (Q_UNLIKELY(!index.isValid())) {
                    qWarning() << "QTreeWidget::mimeData: No index associated with item :" << item;
                    return nullptr;
                }
                indexes << index;
            }
        }
        return d->model->QAbstractItemModel::mimeData(indexes);
    }
    return d->treeModel()->internalMimeData();
}
 
bool QTreeWidget::dropMimeData(QTreeWidgetItem *parent, int index,
                               const QMimeData *data, Qt::DropAction action)
{
    QModelIndex idx;
    if (parent) idx = indexFromItem(parent);
    return model()->QAbstractItemModel::dropMimeData(data, action , index, 0, idx);
}
 
Qt::DropActions QTreeWidget::supportedDropActions() const
{
    return model()->QAbstractItemModel::supportedDropActions() | Qt::MoveAction;
}
 
QModelIndex QTreeWidget::indexFromItem(const QTreeWidgetItem *item, int column) const
{
    Q_D(const QTreeWidget);
    return d->index(item, column);
}
 
QTreeWidgetItem *QTreeWidget::itemFromIndex(const QModelIndex &index) const
{
    Q_D(const QTreeWidget);
    return d->item(index);
}
 
#if QT_CONFIG(draganddrop)
void QTreeWidget::dropEvent(QDropEvent *event) {
    Q_D(QTreeWidget);
    if (event->source() == this && (event->dropAction() == Qt::MoveAction ||
                                    dragDropMode() == QAbstractItemView::InternalMove)) {
        QModelIndex topIndex;
        int col = -1;
        int row = -1;
        // check whether a subclass has already accepted the event, ie. moved the data
        if (!event->isAccepted() && d->dropOn(event, &row, &col, &topIndex)) {
            const QList<QModelIndex> idxs = selectedIndexes();
            QList<QPersistentModelIndex> indexes;
            const int indexesCount = idxs.size();
            indexes.reserve(indexesCount);
            for (const auto &idx : idxs)
                indexes.append(idx);
 
            if (indexes.contains(topIndex))
                return;
 
            // When removing items the drop location could shift
            QPersistentModelIndex dropRow = model()->index(row, col, topIndex);
 
            // Remove the items
            QList<QTreeWidgetItem *> taken;
            for (const auto &index : indexes) {
                QTreeWidgetItem *parent = itemFromIndex(index);
                if (!parent || !parent->parent()) {
                    taken.append(takeTopLevelItem(index.row()));
                } else {
                    taken.append(parent->parent()->takeChild(index.row()));
                }
            }
 
            // insert them back in at their new positions
            for (int i = 0; i < indexes.size(); ++i) {
                // Either at a specific point or appended
                if (row == -1) {
                    if (topIndex.isValid()) {
                        QTreeWidgetItem *parent = itemFromIndex(topIndex);
                        parent->insertChild(parent->childCount(), taken.takeFirst());
                    } else {
                        insertTopLevelItem(topLevelItemCount(), taken.takeFirst());
                    }
                } else {
                    int r = dropRow.row() >= 0 ? dropRow.row() : row;
                    if (topIndex.isValid()) {
                        QTreeWidgetItem *parent = itemFromIndex(topIndex);
                        parent->insertChild(qMin(r, parent->childCount()), taken.takeFirst());
                    } else {
                        insertTopLevelItem(qMin(r, topLevelItemCount()), taken.takeFirst());
                    }
                }
            }
 
            event->accept();
        }
        // either we or a subclass accepted the move event, so assume that the data was
        // moved and that QAbstractItemView shouldn't remove the source when QDrag::exec returns
        if (event->isAccepted())
            d->dropEventMoved = true;
    }
 
    QTreeView::dropEvent(event);
}
#endif
 
void QTreeWidget::setModel(QAbstractItemModel * /*model*/)
{
    Q_ASSERT(!"QTreeWidget::setModel() - Changing the model of the QTreeWidget is not allowed.");
}
 
bool QTreeWidget::event(QEvent *e)
{
    Q_D(QTreeWidget);
    if (e->type() == QEvent::Polish)
        d->treeModel()->executePendingSort();
    return QTreeView::event(e);
}
 
void QTreeModelPrivate::executePendingOperations() const
{
    q_func()->executePendingSort();
}
 
QT_END_NAMESPACE
 
#include "moc_qtreewidget.cpp"
#include "moc_qtreewidget_p.cpp"