qtreeview.cpp

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    \brief whether sorting is enabled

    If this property is true, sorting is enabled for the tree; if the property
    is false, sorting is not enabled. The default value is false.

    \sa sortByColumn()
*/

void QTreeView::setSortingEnabled(bool enable)
{
    Q_D(QTreeView);
    d->sortingEnabled = enable;
    header()->setSortIndicatorShown(enable);
    header()->setClickable(enable);
    if (enable) {
        connect(header(), SIGNAL(sectionClicked(int)), this, SLOT(sortByColumn(int)));
        sortByColumn(header()->sortIndicatorSection());
    } else {
        disconnect(header(), SIGNAL(sectionClicked(int)), this, SLOT(sortByColumn(int)));
    }
}

bool QTreeView::isSortingEnabled() const
{
    Q_D(const QTreeView);
    return d->sortingEnabled;
}

/*!
    \since Qt 4.2
    \property QTreeView::animated
    \brief whether animations are enabled

    If this property is true the treeview will animate expandsion
    and collasping of branches. If this property is false, the treeview
    will expand or collapse branches immediately without showing
    the animation.
*/

void QTreeView::setAnimated(bool animate)
{
    Q_D(QTreeView);
    d->animationsEnabled = animate;
}

bool QTreeView::isAnimated() const
{
    Q_D(const QTreeView);
    return d->animationsEnabled;
}

/*!
    \since 4.2
    \property QTreeView::allColumnsShowFocus
    \brief whether items should show keyboard focus using all columns

    If this property is true all columns will show focus, otherwise only
    one column will show focus.

    The default is false.
*/

void QTreeView::setAllColumnsShowFocus(bool enable)
{
    Q_D(QTreeView);
    if (d->allColumnsShowFocus == enable)
        return;
    if (d->selectionModel) {
        if (enable) {
            QObject::connect(d->selectionModel, SIGNAL(currentChanged(QModelIndex,QModelIndex)),
                             this, SLOT(_q_currentChanged(QModelIndex,QModelIndex)));
        } else {
            QObject::disconnect(d->selectionModel, SIGNAL(currentChanged(QModelIndex,QModelIndex)),
                                this, SLOT(_q_currentChanged(QModelIndex,QModelIndex)));
        }
    }
    d->allColumnsShowFocus = enable;
    d->viewport->update();
}

bool QTreeView::allColumnsShowFocus() const
{
    Q_D(const QTreeView);
    return d->allColumnsShowFocus;
}

/*!
    \property QTreeView::wordWrap
    \brief the item text word-wrapping policy
    \since 4.3

    If this property is true then the item text is wrapped where
    necessary at word-breaks; otherwise it is not wrapped at all.
    This property is false by default.
*/
void QTreeView::setWordWrap(bool on)
{
    Q_D(QTreeView);
    if (d->wrapItemText == on)
        return;
    d->wrapItemText = on;
    d->doDelayedItemsLayout();
}

bool QTreeView::wordWrap() const
{
    Q_D(const QTreeView);
    return d->wrapItemText;
}


/*!
  \reimp
 */
void QTreeView::keyboardSearch(const QString &search)
{
    Q_D(QTreeView);
    if (!d->model->rowCount(d->root) || !d->model->columnCount(d->root))
        return;

    QModelIndex start;
    if (currentIndex().isValid())
        start = currentIndex();
    else
        start = d->model->index(0, 0, d->root);

    QTime now(QTime::currentTime());
    bool skipRow = false;
    if (search.isEmpty()
        || (d->keyboardInputTime.msecsTo(now) > QApplication::keyboardInputInterval())) {
        d->keyboardInput = search;
        skipRow = true;
    } else {
        d->keyboardInput += search;
    }
    d->keyboardInputTime = now;

    // special case for searches with same key like 'aaaaa'
    bool sameKey = false;
    if (d->keyboardInput.length() > 1) {
        int c = d->keyboardInput.count(d->keyboardInput.at(d->keyboardInput.length() - 1));
        sameKey = (c == d->keyboardInput.length());
        if (sameKey)
            skipRow = true;
    }

    // skip if we are searching for the same key or a new search started
    if (skipRow) {
        if (indexBelow(start).isValid())
            start = indexBelow(start);
        else
            start = d->model->index(0, start.column(), d->root);
    }

    d->executePostedLayout();
    int startIndex = d->viewIndex(start);
    if (startIndex <= -1)
        return;

    int previousLevel = -1;
    int bestAbove = -1;
    int bestBelow = -1;
    QString searchString = sameKey ? QString(d->keyboardInput.at(0)) : d->keyboardInput;
    for (int i = 0; i < d->viewItems.count(); ++i) {
        if ((int)d->viewItems.at(i).level > previousLevel) {
            QModelIndex searchFrom = d->viewItems.at(i).index;
            if (searchFrom.parent() == start.parent())
                searchFrom = start;
            QModelIndexList match = d->model->match(searchFrom, Qt::DisplayRole, searchString);
            if (match.count()) {
                int hitIndex = d->viewIndex(match.at(0));
                if (hitIndex >= 0 && hitIndex < startIndex)
                    bestAbove = bestAbove == -1 ? hitIndex : qMin(hitIndex, bestAbove);
                else if (hitIndex >= startIndex)
                    bestBelow = bestBelow == -1 ? hitIndex : qMin(hitIndex, bestBelow);
            }
        }
        previousLevel = d->viewItems.at(i).level;
    }

    QModelIndex index;
    if (bestBelow > -1)
        index = d->viewItems.at(bestBelow).index;
    else if (bestAbove > -1)
        index = d->viewItems.at(bestAbove).index;

    if (index.isValid()) {
        QItemSelectionModel::SelectionFlags flags = (d->selectionMode == SingleSelection
                                                     ? QItemSelectionModel::SelectionFlags(
                                                         QItemSelectionModel::ClearAndSelect
                                                         |d->selectionBehaviorFlags())
                                                     : QItemSelectionModel::SelectionFlags(
                                                         QItemSelectionModel::NoUpdate));
        selectionModel()->setCurrentIndex(index, flags);
    }
}

/*!
  Returns the rectangle on the viewport occupied by the item at \a index.
  If the index is not visible or explicitly hidden, the returned rectangle is invalid.
*/
QRect QTreeView::visualRect(const QModelIndex &index) const
{
    Q_D(const QTreeView);

    if (!d->isIndexValid(index) || isIndexHidden(index))
        return QRect();

    d->executePostedLayout();

    int vi = d->viewIndex(index);
    if (vi < 0)
        return QRect();

    bool spanning = d->viewItems.at(vi).spanning;
    bool firstColumnMoved = (d->header && d->header->logicalIndex(0) != 0);

    // if we have a spanning item, make the selection stretch from left to right
    int x = (spanning ? 0 : columnViewportPosition(index.column()));
    int w = (spanning ? d->header->length() : columnWidth(index.column()));
    // handle indentation
    if (index.column() == 0 && !firstColumnMoved && !spanning) {
        int i = d->indentationForItem(vi);
        x += i;
        w -= i;
    }

    int y = d->coordinateForItem(vi);
    int h = d->itemHeight(vi);

    return QRect(x, y, w, h);
}

/*!
    Scroll the contents of the tree view until the given model item
    \a index is visible. The \a hint parameter specifies more
    precisely where the item should be located after the
    operation.
    If any of the parents of the model item are collapsed, they will
    be expanded to ensure that the model item is visible.
*/
void QTreeView::scrollTo(const QModelIndex &index, ScrollHint hint)
{
    Q_D(QTreeView);

    if (!d->isIndexValid(index))
        return;

    d->executePostedLayout();
    d->updateScrollBars();

    // Expand all parents if the parent(s) of the node are not expanded.
    QModelIndex parent = index.parent();
    while (parent.isValid() && state() == NoState && d->itemsExpandable) {
        if (!isExpanded(parent))
            expand(parent);
        parent = d->model->parent(parent);
    }

    int item = d->viewIndex(index);
    if (item < 0)
        return;

    QRect area = d->viewport->rect();

    // vertical
    if (verticalScrollMode() == QAbstractItemView::ScrollPerItem) {
        int top = verticalScrollBar()->value();
        int bottom = top + verticalScrollBar()->pageStep();
        if (hint == EnsureVisible && item >= top && item < bottom) {
            return; // nothing to do
        } else if (hint == PositionAtTop || item < top) {
            verticalScrollBar()->setValue(item);
        } else { // PositionAtBottom or PositionAtCenter
            int y = (hint == PositionAtCenter
                     ? area.height() / 2
                     : area.height());
            while (y > 0 && item > 0)
                y -= d->itemHeight(item--);
            item += 1 + ((y < 0) ? 1 : 0);
            verticalScrollBar()->setValue(item);
        }
    } else { // ScrollPerPixel
        QRect rect(columnViewportPosition(index.column()),
                   d->coordinateForItem(item), // ### slow for items outside the view
                   columnWidth(index.column()),
                   d->itemHeight(item));

        if (rect.isEmpty())
            return;
        if (hint == EnsureVisible && area.contains(rect)) {
            d->setDirtyRegion(rect);
            return; // nothing to do
        }

        bool above = (hint == EnsureVisible
                      && (rect.top() < area.top()
                          || area.height() < rect.height()));
        bool below = (hint == EnsureVisible
                      && rect.bottom() > area.bottom()
                      && rect.height() < area.height());

        int verticalValue = verticalScrollBar()->value();
        if (hint == PositionAtTop || above)
            verticalValue += rect.top();
        else if (hint == PositionAtBottom || below)
            verticalValue += rect.bottom() - area.height();
        else if (hint == PositionAtCenter)
            verticalValue += rect.top() - ((area.height() - rect.height()) / 2);
        verticalScrollBar()->setValue(verticalValue);
    }

    // horizontal
    int viewportWidth = d->viewport->width();
    int horizontalOffset = d->header->offset();
    int horizontalPosition = d->header->sectionPosition(index.column());
    int cellWidth = d->header->sectionSize(index.column());

    if (hint == PositionAtCenter) {
        horizontalScrollBar()->setValue(horizontalPosition - ((viewportWidth - cellWidth) / 2));
    } else {
        if (horizontalPosition - horizontalOffset < 0 || cellWidth > viewportWidth)
            horizontalScrollBar()->setValue(horizontalPosition);
        else if (horizontalPosition - horizontalOffset + cellWidth > viewportWidth)
            horizontalScrollBar()->setValue(horizontalPosition - viewportWidth + cellWidth);
    }
}

/*!
  \reimp
*/
void QTreeView::timerEvent(QTimerEvent *event)
{
    Q_D(QTreeView);
    if (event->timerId() == d->columnResizeTimerID) {
        updateGeometries();
        killTimer(d->columnResizeTimerID);
        d->columnResizeTimerID = 0;
        QRect rect;
        int viewportHeight = d->viewport->height();
        int viewportWidth = d->viewport->width();
        for (int i = d->columnsToUpdate.size() - 1; i >= 0; --i) {
            int column = d->columnsToUpdate.at(i);
            int x = columnViewportPosition(column);
            if (isRightToLeft())
                rect |= QRect(0, 0, x + columnWidth(column), viewportHeight);
            else
                rect |= QRect(x, 0, viewportWidth - x, viewportHeight);
        }
        d->viewport->update(rect.normalized());
        d->columnsToUpdate.clear();
    } else if (event->timerId() == d->openTimer.timerId()) {
        QPoint pos = d->viewport->mapFromGlobal(QCursor::pos());
        if (state() == QAbstractItemView::DraggingState
            && d->viewport->rect().contains(pos)) {
            QModelIndex index = indexAt(pos);
            setExpanded(index, !isExpanded(index));
        }
        d->openTimer.stop();
    }

    QAbstractItemView::timerEvent(event);
}

/*!
  \reimp
*/
#ifndef QT_NO_DRAGANDDROP
void QTreeView::dragMoveEvent(QDragMoveEvent *event)
{
    Q_D(QTreeView);
    if (d->autoExpandDelay >= 0)
        d->openTimer.start(d->autoExpandDelay, this);
    QAbstractItemView::dragMoveEvent(event);
}
#endif

/*!
  \reimp
*/
bool QTreeView::viewportEvent(QEvent *event)
{
    Q_D(QTreeView);
    switch (event->type()) {
    case QEvent::HoverEnter:
    case QEvent::HoverLeave:
    case QEvent::HoverMove: {
        QHoverEvent *he = static_cast<QHoverEvent*>(event);
        int oldBranch = d->hoverBranch;
        d->hoverBranch = d->itemDecorationAt(he->pos());
        if (oldBranch != d->hoverBranch) {
            QRect oldRect = visualRect(d->modelIndex(oldBranch));
            QRect newRect = visualRect(d->modelIndex(d->hoverBranch));
            viewport()->update(oldRect.left() - d->indent, oldRect.top(), d->indent, oldRect.height());
            viewport()->update(newRect.left() - d->indent, newRect.top(), d->indent, newRect.height());
        }
        break; }
    default:
        break;
    }
    return QAbstractItemView::viewportEvent(event);