qlistview.cpp

qt-x11-opensource-src-4.1.4.tar.gz源码

    // plus adding viewitems to the draggedItems list.
    // We need these items to draw the drag items
    Q_D(QListView);
    QModelIndexList indexes = selectionModel()->selectedIndexes();
    if (indexes.count() > 0 ) {
        QModelIndexList::ConstIterator it = indexes.begin();
        for (; it != indexes.end(); ++it)
            if (model()->flags(*it) & Qt::ItemIsDragEnabled)
                d->draggedItems.push_back(*it);
        QDrag *drag = new QDrag(this);
        drag->setMimeData(model()->mimeData(indexes));
        Qt::DropAction action = drag->start(supportedActions);
        d->draggedItems.clear();
        if (action == Qt::MoveAction)
            d->removeSelectedRows();
    }
}

#endif // QT_NO_DRAGANDDROP

/*!
  \reimp
*/
QStyleOptionViewItem QListView::viewOptions() const
{
    Q_D(const QListView);
    QStyleOptionViewItem option = QAbstractItemView::viewOptions();
    if (!d->iconSize.isValid()) { // otherwise it was already set in abstractitemview
        int pm = (d->viewMode == ListMode
                  ? style()->pixelMetric(QStyle::PM_ListViewIconSize)
                  : style()->pixelMetric(QStyle::PM_IconViewIconSize));
        option.decorationSize = QSize(pm, pm);
    }
    if (d->viewMode == IconMode) {
        option.showDecorationSelected = false;
        option.decorationPosition = QStyleOptionViewItem::Top;
        option.displayAlignment = Qt::AlignCenter;
    } else {
        option.decorationPosition = QStyleOptionViewItem::Left;
    }
    return option;
}

/*!
  \reimp
*/
void QListView::paintEvent(QPaintEvent *e)
{
    Q_D(QListView);
    QStyleOptionViewItem option = viewOptions();
    QPainter painter(d->viewport);
    QRect area = e->rect();

    // if there's nothing to do, clear the area and return
    if (!model()) {
        painter.fillRect(area, option.palette.brush(QPalette::Base));
        return;
    }

    QVector<QModelIndex> toBeRendered;
//     QVector<QRect> rects = e->region().rects();
//     for (int i = 0; i < rects.size(); ++i) {
//         d->intersectingSet(rects.at(i).translated(horizontalOffset(), verticalOffset()));
//         toBeRendered += d->intersectVector;
//     }
    d->intersectingSet(e->rect().translated(horizontalOffset(), verticalOffset()), false);
    toBeRendered = d->intersectVector;

    const QPoint offset = d->scrollDelayOffset;
    const QModelIndex current = currentIndex();
    const QModelIndex hover = d->hover;
    const QAbstractItemModel *itemModel = model();
    const QAbstractItemDelegate *delegate = itemDelegate();
    const QItemSelectionModel *selections = selectionModel();
    const bool focus = (hasFocus() || d->viewport->hasFocus()) && current.isValid();
    const bool alternate = d->alternatingColors;
    const QStyle::State state = option.state;
    const QAbstractItemView::State viewState = this->state();
    const bool enabled = (state & QStyle::State_Enabled) != 0;

    bool alternateBase = false;
    if (alternate && !toBeRendered.isEmpty()) {
        int first = toBeRendered.first().row();
        if (!d->hiddenRows.isEmpty()) {
            for (int row = 0; row < first; ++row) {
                if (!d->hiddenRows.contains(row))
                    alternateBase = !alternateBase;
            }
        } else {
            alternateBase = (first & 1) != 0;
        }
    }

    QVector<QModelIndex>::const_iterator end = toBeRendered.constEnd();
    for (QVector<QModelIndex>::const_iterator it = toBeRendered.constBegin(); it != end; ++it) {
        Q_ASSERT((*it).isValid());
        option.rect = visualRect(*it).translated(offset);
        option.state = state;
        if (selections && selections->isSelected(*it))
            option.state |= QStyle::State_Selected;
        if (enabled) {
            QPalette::ColorGroup cg;
            if ((itemModel->flags(*it) & Qt::ItemIsEnabled) == 0) {
                option.state &= ~QStyle::State_Enabled;
                cg = QPalette::Disabled;
            } else {
                cg = QPalette::Normal;
            }
            option.palette.setCurrentColorGroup(cg);
        }
        if (focus && current == *it) {
            option.state |= QStyle::State_HasFocus;
            if (viewState == EditingState)
                option.state |= QStyle::State_Editing;
        }
        if (*it == hover)
            option.state |= QStyle::State_MouseOver;
        else
            option.state &= ~QStyle::State_MouseOver;

        if (alternate) {
            QBrush fill = alternateBase
                          ? option.palette.brush(QPalette::AlternateBase)
                          : option.palette.brush(QPalette::Base);
            alternateBase = !alternateBase;
            painter.fillRect(option.rect, fill);
        }
        delegate->paint(&painter, option, *it);
    }

#ifndef QT_NO_DRAGANDDROP
    if (!d->draggedItems.isEmpty() && d->viewport->rect().contains(d->draggedItemsPos)) {
        QPoint delta = d->draggedItemsDelta();
        painter.translate(delta.x(), delta.y());
        d->drawItems(&painter, d->draggedItems);
    }

    // Paint the dropIndicator
    d_func()->paintDropIndicator(&painter);
#endif

#ifndef QT_NO_RUBBERBAND
    if (d->elasticBand.isValid()) {
        QStyleOptionRubberBand opt;
        opt.initFrom(this);
        opt.shape = QRubberBand::Rectangle;
        opt.opaque = false;
        opt.rect = d->mapToViewport(d->elasticBand).intersect(
            d->viewport->rect().adjusted(-16, -16, 16, 16));
        painter.save();
        style()->drawControl(QStyle::CE_RubberBand, &opt, &painter);
        painter.restore();
    }
#endif
}

/*!
  \reimp
*/
QModelIndex QListView::indexAt(const QPoint &p) const
{
    Q_D(const QListView);
    QRect rect(p.x() + horizontalOffset(), p.y() + verticalOffset(), 1, 1);
    d->intersectingSet(rect);
    QModelIndex index = d->intersectVector.count() > 0
                        ? d->intersectVector.first() : QModelIndex();
    if (index.isValid() && visualRect(index).contains(p))
        return index;
    return QModelIndex();
}

/*!
  \reimp
*/
int QListView::horizontalOffset() const
{
    return isRightToLeft() ? horizontalScrollBar()->maximum() - horizontalScrollBar()->value() : horizontalScrollBar()->value();
}

/*!
  \reimp
*/
int QListView::verticalOffset() const
{
    return verticalScrollBar()->value();
}

/*!
  \reimp
*/
QModelIndex QListView::moveCursor(CursorAction cursorAction, Qt::KeyboardModifiers modifiers)
{
    Q_D(QListView);
    Q_UNUSED(modifiers);

    if (!model())
        return QModelIndex();

    QModelIndex current = currentIndex();
    if (!current.isValid()) {
        int rowCount = model()->rowCount(rootIndex());
        if (!rowCount)
            return QModelIndex();
        int row = 0;
        while (row < rowCount && isRowHidden(row))
            ++row;
        if (row >= rowCount)
            return QModelIndex();
        return model()->index(row, 0, rootIndex());
    }

    QRect rect = rectForIndex(current);
    if (rect.isEmpty()) {
        return model()->index(0, 0, rootIndex());
    }

    QSize contents = d->contentsSize;
    QPoint pos = rect.center();
    d->intersectVector.clear();

    switch (cursorAction) {
    case MoveLeft:
        while (d->intersectVector.isEmpty()) {
            rect.translate(-rect.width(), 0);
            if (rect.right() <= 0)
                return current;
            if (rect.left() < 0)
                rect.setLeft(0);
            d->intersectingSet(rect);
            // don't get current in this set
            int idx = d->intersectVector.indexOf(current);
            if (idx > -1)
                d->intersectVector.remove(idx);
        }
        return d->closestIndex(pos, d->intersectVector);
    case MoveRight:
        while (d->intersectVector.isEmpty()) {
            rect.translate(rect.width(), 0);
            if (rect.left() >= contents.width())
                return current;
            if (rect.right() > contents.width())
                rect.setRight(contents.width());
            d->intersectingSet(rect);
            // don't get current in this set
            int idx = d->intersectVector.indexOf(current);
            if (idx > -1)
                d->intersectVector.remove(idx);
        }
        return d->closestIndex(pos, d->intersectVector);
    case MovePageUp:
        rect.moveTop(rect.top() - d->viewport->height());
        if (rect.top() < rect.height())
            rect.moveTop(rect.height());
    case MovePrevious:
    case MoveUp:
        while (d->intersectVector.isEmpty()) {
            rect.translate(0, -rect.height());
            if (rect.bottom() <= 0) {
#ifdef QT_KEYPAD_NAVIGATION
                if (QApplication::keypadNavigationEnabled())
                    return model()->index(d->batchStartRow - 1, d->column, rootIndex());
#endif
                return current;
            }
            if (rect.top() < 0)
                rect.setTop(0);
            d->intersectingSet(rect);
            // don't get current in this set
            int idx = d->intersectVector.indexOf(current);
            if (idx > -1)
                d->intersectVector.remove(idx);
        }
        return d->closestIndex(pos, d->intersectVector);
    case MovePageDown:
        rect.moveTop(rect.top() + d->viewport->height());
        if (rect.bottom() > contents.height() - rect.height())
            rect.moveBottom(contents.height() - rect.height());
    case MoveNext:
    case MoveDown:
        while (d->intersectVector.isEmpty()) {
            rect.translate(0, rect.height());
            if (rect.top() >= contents.height()) {
#ifdef QT_KEYPAD_NAVIGATION
                if (QApplication::keypadNavigationEnabled())
                    return model()->index(0, d->column, rootIndex());
#endif
                return current;
            }
            if (rect.bottom() > contents.height())
                rect.setBottom(contents.height());
            d->intersectingSet(rect);
            // don't get current in this set
            int idx = d->intersectVector.indexOf(current);
            if (idx > -1)
                d->intersectVector.remove(idx);
        }
        return d->closestIndex(pos, d->intersectVector);
    case MoveHome:
        return model()->index(0, d->column, rootIndex());
    case MoveEnd:
        return model()->index(d->batchStartRow - 1, d->column, rootIndex());
    }

    return current;
}

/*!
    Returns the rectangle of the item at position \a index in the
    model. The rectangle is in contents coordinates.
*/
QRect QListView::rectForIndex(const QModelIndex &index) const
{
    Q_D(const QListView);
    if (!index.isValid()
        || index.parent() != rootIndex()
        || index.column() != d->column
        || isIndexHidden(index))
        return QRect();
    d->executePostedLayout();
    QListViewItem item = d->indexToListViewItem(index);
    return d->viewItemRect(item);
}

/*!
    \since 4.1

    Sets the contents position of the item at \a index in the model to the given
    \a position.
    If the list view's movement mode is Static, this function will have no
    effect.
*/
void QListView::setPositionForIndex(const QPoint &position, const QModelIndex &index)
{
    Q_D(QListView);
    if (d->movement == Static
        || !index.isValid()
        || index.parent() != rootIndex()
        || index.column() != d->column)
        return;
    d->executePostedLayout();
    if (index.row() >= d->items.count())
        return;
    d->setDirtyRegion(visualRect(index)); // update old position
    d->moveItem(index.row(), position);
    d->setDirtyRegion(visualRect(index)); // update new position
}

/*!
  \reimp
*/
void QListView::setSelection(const QRect &rect, QItemSelectionModel::SelectionFlags command)
{
    Q_D(QListView);
    if (!selectionModel())
        return;

    d->intersectingSet(rect.translated(horizontalOffset(), verticalOffset()));

    QItemSelection selection;
    QModelIndex tl;
    QModelIndex br;
    QVector<QModelIndex>::iterator it = d->intersectVector.begin();
    for (; it != d->intersectVector.end(); ++it) {
        if (!tl.isValid() && !br.isValid()) {
            tl = br = *it;
        } else if ((*it).row() == (tl.row() - 1)) {
            tl = *it; // expand current range
        } else if ((*it).row() == (br.row() + 1)) {
            br = (*it); // expand current range
        } else {
            selection.select(tl, br); // select current range
            tl = br = *it; // start new range
        }
    }
    if (tl.isValid() && br.isValid())
        selection.select(tl, br);

    selectionModel()->select(selection, command);
}

/*!
  \reimp
*/
QRegion QListView::visualRegionForSelection(const QItemSelection &selection) const
{
    Q_D(const QListView);
    // ### NOTE: this is a potential bottleneck in non-static mode
    int c = d->column;
    QRegion selectionRegion;
    for (int i = 0; i < selection.count(); ++i) {
        if (!selection.at(i).isValid())
            continue;
        QModelIndex parent = selection.at(i).topLeft().parent();
        int t = selection.at(i).topLeft().row();
        int b = selection.at(i).bottomRight().row();
        if (d->movement != Static || d->wrap) { // in non-static mode, we have to go through all selected items
            for (int r = t; r <= b; ++r)
                selectionRegion += QRegion(visualRect(d->model->index(r, c, parent)));
        } else { // in static mode, we can optimize a bit
            QRect rect(visualRect(d->model->index(t, c, parent)).topLeft(),
                       visualRect(d->model->index(b, c, parent)).bottomRight());
            selectionRegion += QRegion(rect);
        }
    }