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Diffstat (limited to 'src/widgets/itemviews/qtreewidgetitemiterator.cpp')
| -rw-r--r-- | src/widgets/itemviews/qtreewidgetitemiterator.cpp | 458 |
1 files changed, 458 insertions, 0 deletions
diff --git a/src/widgets/itemviews/qtreewidgetitemiterator.cpp b/src/widgets/itemviews/qtreewidgetitemiterator.cpp new file mode 100644 index 0000000000..579c5acdf6 --- /dev/null +++ b/src/widgets/itemviews/qtreewidgetitemiterator.cpp @@ -0,0 +1,458 @@ +/**************************************************************************** +** +** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies). +** All rights reserved. +** Contact: Nokia Corporation (qt-info@nokia.com) +** +** This file is part of the QtGui module of the Qt Toolkit. +** +** $QT_BEGIN_LICENSE:LGPL$ +** GNU Lesser General Public License Usage +** This file may be used under the terms of the GNU Lesser General Public +** License version 2.1 as published by the Free Software Foundation and +** appearing in the file LICENSE.LGPL included in the packaging of this +** file. Please review the following information to ensure the GNU Lesser +** General Public License version 2.1 requirements will be met: +** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. +** +** In addition, as a special exception, Nokia gives you certain additional +** rights. These rights are described in the Nokia Qt LGPL Exception +** version 1.1, included in the file LGPL_EXCEPTION.txt in this package. +** +** 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. +** +** Other Usage +** Alternatively, this file may be used in accordance with the terms and +** conditions contained in a signed written agreement between you and Nokia. +** +** +** +** +** +** $QT_END_LICENSE$ +** +****************************************************************************/ + +#include <private/qtreewidgetitemiterator_p.h> +#include "qtreewidget.h" +#include "qtreewidget_p.h" +#include "qwidgetitemdata_p.h" + +#ifndef QT_NO_TREEWIDGET + +QT_BEGIN_NAMESPACE + +/*! + \class QTreeWidgetItemIterator + \ingroup model-view + \brief The QTreeWidgetItemIterator class provides a way to iterate over the + items in a QTreeWidget instance. + + The iterator will walk the items in a pre-order traversal order, thus visiting the + parent node \e before it continues to the child nodes. + + For example, the following code examples each item in a tree, checking the + text in the first column against a user-specified search string: + + \snippet doc/src/snippets/qtreewidgetitemiterator-using/mainwindow.cpp 0 + + It is also possible to filter out certain types of node by passing certain + \l{IteratorFlag}{flags} to the constructor of QTreeWidgetItemIterator. + + \sa QTreeWidget, {Model/View Programming}, QTreeWidgetItem +*/ + +/*! + Constructs an iterator for the same QTreeWidget as \a it. The + current iterator item is set to point on the current item of \a it. +*/ + +QTreeWidgetItemIterator::QTreeWidgetItemIterator(const QTreeWidgetItemIterator &it) + : d_ptr(new QTreeWidgetItemIteratorPrivate(*(it.d_ptr))), + current(it.current), flags(it.flags) +{ + Q_D(QTreeWidgetItemIterator); + Q_ASSERT(d->m_model); + d->m_model->iterators.append(this); +} + +/*! + Constructs an iterator for the given \a widget that uses the specified \a flags + to determine which items are found during iteration. + The iterator is set to point to the first top-level item contained in the widget, + or the next matching item if the top-level item doesn't match the flags. + + \sa QTreeWidgetItemIterator::IteratorFlag +*/ + +QTreeWidgetItemIterator::QTreeWidgetItemIterator(QTreeWidget *widget, IteratorFlags flags) +: current(0), flags(flags) +{ + Q_ASSERT(widget); + QTreeModel *model = qobject_cast<QTreeModel*>(widget->model()); + Q_ASSERT(model); + d_ptr.reset(new QTreeWidgetItemIteratorPrivate(this, model)); + model->iterators.append(this); + if (!model->rootItem->children.isEmpty()) current = model->rootItem->children.first(); + if (current && !matchesFlags(current)) + ++(*this); +} + +/*! + Constructs an iterator for the given \a item that uses the specified \a flags + to determine which items are found during iteration. + The iterator is set to point to \a item, or the next matching item if \a item + doesn't match the flags. + + \sa QTreeWidgetItemIterator::IteratorFlag +*/ + +QTreeWidgetItemIterator::QTreeWidgetItemIterator(QTreeWidgetItem *item, IteratorFlags flags) + : d_ptr(new QTreeWidgetItemIteratorPrivate( + this, qobject_cast<QTreeModel*>(item->view->model()))), + current(item), flags(flags) +{ + Q_D(QTreeWidgetItemIterator); + Q_ASSERT(item); + QTreeModel *model = qobject_cast<QTreeModel*>(item->view->model()); + Q_ASSERT(model); + model->iterators.append(this); + + // Initialize m_currentIndex and m_parentIndex as it would be if we had traversed from + // the beginning. + QTreeWidgetItem *parent = item; + parent = parent->parent(); + QList<QTreeWidgetItem *> children = parent ? parent->children : d->m_model->rootItem->children; + d->m_currentIndex = children.indexOf(item); + + while (parent) { + QTreeWidgetItem *itm = parent; + parent = parent->parent(); + QList<QTreeWidgetItem *> children = parent ? parent->children : d->m_model->rootItem->children; + int index = children.indexOf(itm); + d->m_parentIndex.prepend(index); + } + + if (current && !matchesFlags(current)) + ++(*this); +} + +/*! + Destroys the iterator. +*/ + +QTreeWidgetItemIterator::~QTreeWidgetItemIterator() +{ + d_func()->m_model->iterators.removeAll(this); +} + +/*! + Assignment. Makes a copy of \a it and returns a reference to its + iterator. +*/ + +QTreeWidgetItemIterator &QTreeWidgetItemIterator::operator=(const QTreeWidgetItemIterator &it) +{ + Q_D(QTreeWidgetItemIterator); + if (d_func()->m_model != it.d_func()->m_model) { + d_func()->m_model->iterators.removeAll(this); + it.d_func()->m_model->iterators.append(this); + } + current = it.current; + flags = it.flags; + d->operator=(*it.d_func()); + return *this; +} + +/*! + The prefix ++ operator (++it) advances the iterator to the next matching item + and returns a reference to the resulting iterator. + Sets the current pointer to 0 if the current item is the last matching item. +*/ + +QTreeWidgetItemIterator &QTreeWidgetItemIterator::operator++() +{ + if (current) + do { + current = d_func()->next(current); + } while (current && !matchesFlags(current)); + return *this; +} + +/*! + The prefix -- operator (--it) advances the iterator to the previous matching item + and returns a reference to the resulting iterator. + Sets the current pointer to 0 if the current item is the first matching item. +*/ + +QTreeWidgetItemIterator &QTreeWidgetItemIterator::operator--() +{ + if (current) + do { + current = d_func()->previous(current); + } while (current && !matchesFlags(current)); + return *this; +} + +/*! + \internal +*/ +bool QTreeWidgetItemIterator::matchesFlags(const QTreeWidgetItem *item) const +{ + if (!item) + return false; + + if (flags == All) + return true; + + { + Qt::ItemFlags itemFlags = item->flags(); + if ((flags & Selectable) && !(itemFlags & Qt::ItemIsSelectable)) + return false; + if ((flags & NotSelectable) && (itemFlags & Qt::ItemIsSelectable)) + return false; + if ((flags & DragEnabled) && !(itemFlags & Qt::ItemIsDragEnabled)) + return false; + if ((flags & DragDisabled) && (itemFlags & Qt::ItemIsDragEnabled)) + return false; + if ((flags & DropEnabled) && !(itemFlags & Qt::ItemIsDropEnabled)) + return false; + if ((flags & DropDisabled) && (itemFlags & Qt::ItemIsDropEnabled)) + return false; + if ((flags & Enabled) && !(itemFlags & Qt::ItemIsEnabled)) + return false; + if ((flags & Disabled) && (itemFlags & Qt::ItemIsEnabled)) + return false; + if ((flags & Editable) && !(itemFlags & Qt::ItemIsEditable)) + return false; + if ((flags & NotEditable) && (itemFlags & Qt::ItemIsEditable)) + return false; + } + + if (flags & (Checked|NotChecked)) { + // ### We only test the check state for column 0 + Qt::CheckState check = item->checkState(0); + // PartiallyChecked matches as Checked. + if ((flags & Checked) && (check == Qt::Unchecked)) + return false; + if ((flags & NotChecked) && (check != Qt::Unchecked)) + return false; + } + + if ((flags & HasChildren) && !item->childCount()) + return false; + if ((flags & NoChildren) && item->childCount()) + return false; + + if ((flags & Hidden) && !item->isHidden()) + return false; + if ((flags & NotHidden) && item->isHidden()) + return false; + + if ((flags & Selected) && !item->isSelected()) + return false; + if ((flags & Unselected) && item->isSelected()) + return false; + + return true; +} + +/* + * Implementation of QTreeWidgetItemIteratorPrivate + */ +QTreeWidgetItem* QTreeWidgetItemIteratorPrivate::nextSibling(const QTreeWidgetItem* item) const +{ + Q_ASSERT(item); + QTreeWidgetItem *next = 0; + if (QTreeWidgetItem *par = item->parent()) { + int i = par->indexOfChild(const_cast<QTreeWidgetItem*>(item)); + next = par->child(i + 1); + } else { + QTreeWidget *tw = item->treeWidget(); + int i = tw->indexOfTopLevelItem(const_cast<QTreeWidgetItem*>(item)); + next = tw->topLevelItem(i + 1); + } + return next; +} + +QTreeWidgetItem *QTreeWidgetItemIteratorPrivate::next(const QTreeWidgetItem *current) +{ + if (!current) return 0; + + QTreeWidgetItem *next = 0; + if (current->childCount()) { + // walk the child + m_parentIndex.push(m_currentIndex); + m_currentIndex = 0; + next = current->child(0); + } else { + // walk the sibling + QTreeWidgetItem *parent = current->parent(); + next = parent ? parent->child(m_currentIndex + 1) + : m_model->rootItem->child(m_currentIndex + 1); + while (!next && parent) { + // if we had no sibling walk up the parent and try the sibling of that + parent = parent->parent(); + m_currentIndex = m_parentIndex.pop(); + next = parent ? parent->child(m_currentIndex + 1) + : m_model->rootItem->child(m_currentIndex + 1); + } + if (next) ++(m_currentIndex); + } + return next; +} + +QTreeWidgetItem *QTreeWidgetItemIteratorPrivate::previous(const QTreeWidgetItem *current) +{ + if (!current) return 0; + + QTreeWidgetItem *prev = 0; + // walk the previous sibling + QTreeWidgetItem *parent = current->parent(); + prev = parent ? parent->child(m_currentIndex - 1) + : m_model->rootItem->child(m_currentIndex - 1); + if (prev) { + // Yes, we had a previous sibling but we need go down to the last leafnode. + --m_currentIndex; + while (prev && prev->childCount()) { + m_parentIndex.push(m_currentIndex); + m_currentIndex = prev->childCount() - 1; + prev = prev->child(m_currentIndex); + } + } else if (parent) { + m_currentIndex = m_parentIndex.pop(); + prev = parent; + } + return prev; +} + +void QTreeWidgetItemIteratorPrivate::ensureValidIterator(const QTreeWidgetItem *itemToBeRemoved) +{ + Q_Q(QTreeWidgetItemIterator); + Q_ASSERT(itemToBeRemoved); + + if (!q->current) return; + QTreeWidgetItem *nextItem = q->current; + + // Do not walk to the ancestor to find the other item if they have the same parent. + if (nextItem->parent() != itemToBeRemoved->parent()) { + while (nextItem->parent() && nextItem != itemToBeRemoved) { + nextItem = nextItem->parent(); + } + } + // If the item to be removed is an ancestor of the current iterator item, + // we need to adjust the iterator. + if (nextItem == itemToBeRemoved) { + QTreeWidgetItem *parent = nextItem; + nextItem = 0; + while (parent && !nextItem) { + nextItem = nextSibling(parent); + parent = parent->parent(); + } + if (nextItem) { + // Ooooh... Set the iterator to the next valid item + *q = QTreeWidgetItemIterator(nextItem, q->flags); + if (!(q->matchesFlags(nextItem))) ++(*q); + } else { + // set it to null. + q->current = 0; + m_parentIndex.clear(); + return; + } + } + if (nextItem->parent() == itemToBeRemoved->parent()) { + // They have the same parent, i.e. we have to adjust the m_currentIndex member of the iterator + // if the deleted item is to the left of the nextItem. + + QTreeWidgetItem *par = itemToBeRemoved->parent(); // We know they both have the same parent. + QTreeWidget *tw = itemToBeRemoved->treeWidget(); // ..and widget + int indexOfItemToBeRemoved = par ? par->indexOfChild(const_cast<QTreeWidgetItem *>(itemToBeRemoved)) + : tw->indexOfTopLevelItem(const_cast<QTreeWidgetItem *>(itemToBeRemoved)); + int indexOfNextItem = par ? par->indexOfChild(nextItem) : tw->indexOfTopLevelItem(nextItem); + + if (indexOfItemToBeRemoved <= indexOfNextItem) { + // A sibling to the left of us was deleted, adjust the m_currentIndex member of the iterator. + // Note that the m_currentIndex will be wrong until the item is actually removed! + m_currentIndex--; + } + } +} + +/*! + \fn const QTreeWidgetItemIterator QTreeWidgetItemIterator::operator++(int) + + The postfix ++ operator (it++) advances the iterator to the next matching item + and returns an iterator to the previously current item. +*/ + +/*! + \fn QTreeWidgetItemIterator &QTreeWidgetItemIterator::operator+=(int n) + + Makes the iterator go forward by \a n matching items. (If n is negative, the + iterator goes backward.) + + If the current item is beyond the last item, the current item pointer is + set to 0. Returns the resulting iterator. +*/ + +/*! + \fn const QTreeWidgetItemIterator QTreeWidgetItemIterator::operator--(int) + + The postfix -- operator (it--) makes the preceding matching item current and returns an iterator to the previously current item. +*/ + +/*! + \fn QTreeWidgetItemIterator &QTreeWidgetItemIterator::operator-=(int n) + + Makes the iterator go backward by \a n matching items. (If n is negative, the + iterator goes forward.) + + If the current item is ahead of the last item, the current item pointer is + set to 0. Returns the resulting iterator. +*/ + +/*! + \fn QTreeWidgetItem *QTreeWidgetItemIterator::operator*() const + + Dereference operator. Returns a pointer to the current item. +*/ + + +/*! + \enum QTreeWidgetItemIterator::IteratorFlag + + These flags can be passed to a QTreeWidgetItemIterator constructor + (OR-ed together if more than one is used), so that the iterator + will only iterate over items that match the given flags. + + \value All + \value Hidden + \value NotHidden + \value Selected + \value Unselected + \value Selectable + \value NotSelectable + \value DragEnabled + \value DragDisabled + \value DropEnabled + \value DropDisabled + \value HasChildren + \value NoChildren + \value Checked + \value NotChecked + \value Enabled + \value Disabled + \value Editable + \value NotEditable + \value UserFlag +*/ + +QT_END_NAMESPACE + +#endif // QT_NO_TREEWIDGET |