qtreeview.cpp

奇趣公司比较新的qt/emd版本

    int i = d->itemDecorationAt(event->pos());
    if (i == -1) {
        i = d->itemAtCoordinate(event->y());
        if (i == -1)
            return; // user clicked outside the items

        const QModelIndex &index = d->viewItems.at(i).index;

        int column = d->header->logicalIndexAt(event->x());
        QPersistentModelIndex persistent = index.sibling(index.row(), column);

        if (d->pressedIndex != persistent) {
            mousePressEvent(event);
            return;
        }

        // signal handlers may change the model
        emit doubleClicked(persistent);

        if (!persistent.isValid())
            return;

        if (edit(persistent, DoubleClicked, event) || state() != NoState)
            return; // the double click triggered editing

        if (!style()->styleHint(QStyle::SH_ItemView_ActivateItemOnSingleClick, 0, this))
            emit activated(persistent);

        d->executePostedLayout(); // we need to make sure viewItems is updated
        if (d->itemsExpandable && d->hasVisibleChildren(persistent)) {
            if (!((i < d->viewItems.count()) && (d->viewItems.at(i).index == persistent))) {
                // find the new index of the item
                for (i = 0; i < d->viewItems.count(); ++i) {
                    if (d->viewItems.at(i).index == persistent)
                        break;
                }
                if (i == d->viewItems.count())
                    return;
            }
            if (d->viewItems.at(i).expanded)
                d->collapse(i, true);
            else
                d->expand(i, true);
            updateGeometries();
            viewport()->update();
        }
    }
}

/*!
  \reimp
*/
void QTreeView::mouseMoveEvent(QMouseEvent *event)
{
    Q_D(QTreeView);
    if (d->itemDecorationAt(event->pos()) == -1) // ### what about expanding/collapsing state ?
        QAbstractItemView::mouseMoveEvent(event);
}

/*!
  \reimp
*/
void QTreeView::keyPressEvent(QKeyEvent *event)
{
    Q_D(QTreeView);
    QModelIndex current = currentIndex();
    if (d->isIndexValid(current) && d->model) {
        switch (event->key()) {
        case Qt::Key_Asterisk: {
            QStack<QModelIndex> parents;
            parents.push(current);
            if (d->itemsExpandable) {
                while (!parents.isEmpty()) {
                    QModelIndex parent = parents.pop();
                    for (int row = 0; row < d->model->rowCount(parent); ++row) {
                        QModelIndex child = d->model->index(row, 0, parent);
                        if (!d->isIndexValid(child))
                            break;
                        parents.push(child);
                        expand(child);
                    }
                }
                expand(current);
            }
            break; }
        case Qt::Key_Plus:
            expand(current);
            break;
        case Qt::Key_Minus:
            collapse(current);
            break;
        }
    }

    QAbstractItemView::keyPressEvent(event);
}

/*!
  \reimp
*/
QModelIndex QTreeView::indexAt(const QPoint &point) const
{
    Q_D(const QTreeView);
    d->executePostedLayout();

    int visualIndex = d->itemAtCoordinate(point.y());
    QModelIndex idx = d->modelIndex(visualIndex);
    if (!idx.isValid())
        return QModelIndex();

    if (d->viewItems.at(visualIndex).spanning)
        return idx;

    int column = d->columnAt(point.x());
    if (column == idx.column())
        return idx;
    if (column < 0)
        return QModelIndex();
    return d->model->sibling(idx.row(), column, idx);
}

/*!
  Returns the model index of the item above \a index.
*/
QModelIndex QTreeView::indexAbove(const QModelIndex &index) const
{
    Q_D(const QTreeView);
    if (!d->isIndexValid(index))
        return QModelIndex();
    d->executePostedLayout();
    int i = d->viewIndex(index);
    if (--i < 0)
        return QModelIndex();
    return d->viewItems.at(i).index;
}

/*!
  Returns the model index of the item below \a index.
*/
QModelIndex QTreeView::indexBelow(const QModelIndex &index) const
{
    Q_D(const QTreeView);
    if (!d->isIndexValid(index))
        return QModelIndex();
    d->executePostedLayout();
    int i = d->viewIndex(index);
    if (++i >= d->viewItems.count())
        return QModelIndex();
    return d->viewItems.at(i).index;
}

/*!
    \internal

    Lays out the items in the tree view.
*/
void QTreeView::doItemsLayout()
{
    Q_D(QTreeView);
    d->viewItems.clear(); // prepare for new layout
    QModelIndex parent = d->root;
    if (d->model->hasChildren(parent)) {
        d->layout(-1);
        d->reexpandChildren(parent);
    }
    QAbstractItemView::doItemsLayout();
    d->header->doItemsLayout();
}

/*!
  \reimp
*/
void QTreeView::reset()
{
    Q_D(QTreeView);
    d->expandedIndexes.clear();
    d->hiddenIndexes.clear();
    d->spanningIndexes.clear();
    d->viewItems.clear();
    QAbstractItemView::reset();
}

/*!
  Returns the horizontal offset of the items in the treeview.

  Note that the tree view uses the horizontal header section
  positions to determine the positions of columns in the view.

  \sa verticalOffset()
*/
int QTreeView::horizontalOffset() const
{
    Q_D(const QTreeView);
    return d->header->offset();
}

/*!
  Returns the vertical offset of the items in the tree view.

  \sa horizontalOffset()
*/
int QTreeView::verticalOffset() const
{
    Q_D(const QTreeView);
    if (verticalScrollMode() == QAbstractItemView::ScrollPerItem) {
        if (uniformRowHeights())
            return verticalScrollBar()->value() * d->defaultItemHeight;
        // If we are scrolling per item and have non-uniform row heights,
        // finding the vertical offset in pixels is going to be relatively slow.
        // ### find a faster way to do this
        int offset = 0;
        for (int i = 0; i < d->viewItems.count(); ++i) {
            if (i == verticalScrollBar()->value())
                return offset;
            offset += d->itemHeight(i);
        }
        return 0;
    }
    // scroll per pixel
    return verticalScrollBar()->value();
}

/*!
    Move the cursor in the way described by \a cursorAction, using the
    information provided by the button \a modifiers.
*/
QModelIndex QTreeView::moveCursor(CursorAction cursorAction, Qt::KeyboardModifiers modifiers)
{
    Q_D(QTreeView);
    Q_UNUSED(modifiers);

    d->executePostedLayout();

    QModelIndex current = currentIndex();
    if (!current.isValid()) {
        int i = 0;
        while (i < d->viewItems.count() && d->hiddenIndexes.contains(d->viewItems.at(i).index))
            ++i;
        return d->viewItems.value(i).index;
    }
    int vi = qMax(0, d->viewIndex(current));
    switch (cursorAction) {
    case MoveNext:
    case MoveDown:
#ifdef QT_KEYPAD_NAVIGATION
        if (vi == d->viewItems.count()-1 && QApplication::keypadNavigationEnabled())
            return d->model->index(0, 0, d->root);
#endif
        return d->modelIndex(d->below(vi));
    case MovePrevious:
    case MoveUp:
#ifdef QT_KEYPAD_NAVIGATION
        if (vi == 0 && QApplication::keypadNavigationEnabled())
            return d->modelIndex(d->viewItems.count() - 1);
#endif
        return d->modelIndex(d->above(vi));
    case MoveLeft: {
        QScrollBar *sb = horizontalScrollBar();
        if (vi < d->viewItems.count() && d->viewItems.at(vi).expanded && d->itemsExpandable && sb->value() == sb->minimum())
            d->collapse(vi, true);
        else {
            bool descend = style()->styleHint(QStyle::SH_ItemView_ArrowKeysNavigateIntoChildren, 0, this);
            if (descend) {
                QModelIndex par = current.parent();
                if (par.isValid())
                    return par;
                else
                    descend = false;
            }
            if (!descend) {
                sb->setValue(sb->value() - sb->singleStep());
            }

        }
        updateGeometries();
        viewport()->update();
        break;
    }
    case MoveRight:
        if (vi < d->viewItems.count() && !d->viewItems.at(vi).expanded && d->itemsExpandable) {
            d->expand(vi, true);
        } else {
            bool descend = style()->styleHint(QStyle::SH_ItemView_ArrowKeysNavigateIntoChildren, 0, this);
            if (descend) {
                QModelIndex idx = d->modelIndex(d->below(vi));
                if (idx.parent() == current)
                    return idx;
                else
                    descend = false;
            }
            if (!descend) {
                QScrollBar *sb = horizontalScrollBar();
                sb->setValue(sb->value() + sb->singleStep());
            }
        }
        updateGeometries();
        viewport()->update();
        break;
    case MovePageUp:
        return d->modelIndex(d->pageUp(vi));
    case MovePageDown:
        return d->modelIndex(d->pageDown(vi));
    case MoveHome:
        return d->model->index(0, 0, d->root);
    case MoveEnd:
        return d->modelIndex(d->viewItems.count() - 1);
    }
    return current;
}

/*!
  Applies the selection \a command to the items in or touched by the
  rectangle, \a rect.

  \sa selectionCommand()
*/
void QTreeView::setSelection(const QRect &rect, QItemSelectionModel::SelectionFlags command)
{
    Q_D(QTreeView);
    if (!selectionModel() || rect.isNull())
        return;

    d->executePostedLayout();
    QPoint tl(isRightToLeft() ? qMax(rect.left(), rect.right())
              : qMin(rect.left(), rect.right()), qMin(rect.top(), rect.bottom()));
    QPoint br(isRightToLeft() ? qMin(rect.left(), rect.right()) :
              qMax(rect.left(), rect.right()), qMax(rect.top(), rect.bottom()));
    QModelIndex topLeft = indexAt(tl);
    QModelIndex bottomRight = indexAt(br);
    if (!topLeft.isValid() && !bottomRight.isValid())
        return;
    if (!topLeft.isValid() && !d->viewItems.isEmpty())
        topLeft = d->viewItems.first().index;
    if (!bottomRight.isValid() && !d->viewItems.isEmpty()) {
        const int column = d->header->logicalIndex(d->header->count() - 1);
        const QModelIndex index = d->viewItems.last().index;
        bottomRight = index.sibling(index.row(), column);
    }

    if (selectionBehavior() != SelectRows) {
        QItemSelection selection;
        if (topLeft.isValid() && bottomRight.isValid()) {
            selection.append(QItemSelectionRange(topLeft, bottomRight));
            selectionModel()->select(selection, command);
        }
    } else {
        d->select(d->viewIndex(topLeft), d->viewIndex(bottomRight), command);
    }
}

/*!
  Returns the rectangle from the viewport of the items in the given
  \a selection.
*/
QRegion QTreeView::visualRegionForSelection(const QItemSelection &selection) const
{
    Q_D(const QTreeView);
    if (selection.isEmpty())
        return QRegion();

    QRegion selectionRegion;
    for (int i = 0; i < selection.count(); ++i) {
        QItemSelectionRange range = selection.at(i);
        if (!range.isValid())
            continue;
        QModelIndex parent = range.parent();
        QModelIndex leftIndex = range.topLeft();
        int columnCount = d->model->columnCount(parent);
        while (leftIndex.isValid() && isIndexHidden(leftIndex)) {
            if (leftIndex.column() + 1 < columnCount)
                leftIndex = d->model->index(leftIndex.row(), leftIndex.column() + 1, parent);
            else
                leftIndex = QModelIndex();
        }
        if (!leftIndex.isValid())
            continue;
        const QRect leftRect = visualRect(leftIndex);
        int top = leftRect.top();
        QModelIndex rightIndex = range.bottomRight();
        while (rightIndex.isValid() && isIndexHidden(rightIndex)) {
            if (rightIndex.column() - 1 >= 0)
                rightIndex = d->model->index(rightIndex.row(), rightIndex.column() - 1, parent);
            else
                rightIndex = QModelIndex();
        }
        if (!rightIndex.isValid())
            continue;
        const QRect rightRect = visualRect(rightIndex);
        int bottom = rightRect.bottom();
        if (top > bottom)
            qSwap<int>(top, bottom);
        int height = bottom - top + 1;
        if (d->header->sectionsMoved()) {
            for (int c = range.left(); c <= range.right(); ++c)
                selectionRegion += QRegion(QRect(columnViewportPosition(c), top,
                                                 columnWidth(c), height));
        } else {
            QRect combined = leftRect|rightRect;
            combined.setX(columnViewportPosition(isRightToLeft() ? range.right() : range.left()));