qlistview.cpp

奇趣公司比较新的qt/emd版本

    }
    // FIXME: Until the we can provide a proper drop indicator
    // in IconMode, it makes no sense to show it
    if (d->viewMode == ListMode)
        d->paintDropIndicator(&painter);
#endif

#ifndef QT_NO_RUBBERBAND
    // #### move this implementation into a dynamic class
    if (d->showElasticBand && d->elasticBand.isValid()) {
        QStyleOptionRubberBand opt;
        opt.initFrom(this);
        opt.shape = QRubberBand::Rectangle;
        opt.opaque = false;
        opt.rect = d->mapToViewport(d->elasticBand, false).intersected(
            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.last() : QModelIndex();
    if (index.isValid() && visualRect(index).contains(p))
        return index;
    return QModelIndex();
}

/*!
  \reimp
*/
int QListView::horizontalOffset() const
{
    Q_D(const QListView);
    // ### split into static and dynamic
    if (horizontalScrollMode() == QAbstractItemView::ScrollPerItem && d->viewMode == ListMode) {
        if (d->isWrapping()) {
            if (d->flow == TopToBottom && !d->staticListView->segmentPositions.isEmpty()) {
                const int max = d->staticListView->segmentPositions.count() - 1;
                int currentValue = qBound(0, horizontalScrollBar()->value(), max);
                int position = d->staticListView->segmentPositions.at(currentValue);
                int maximumValue = qBound(0, horizontalScrollBar()->maximum(), max);
                int maximum = d->staticListView->segmentPositions.at(maximumValue);
                return (isRightToLeft() ? maximum - position : position);
            }
            //return 0;
        } else {
            if (d->flow == LeftToRight && !d->staticListView->flowPositions.isEmpty()) {
                int position = d->staticListView->flowPositions.at(horizontalScrollBar()->value());
                int maximum = d->staticListView->flowPositions.at(horizontalScrollBar()->maximum());
                return (isRightToLeft() ? maximum - position : position);
            }
            //return 0;
        }
    }
    return (isRightToLeft()
            ? horizontalScrollBar()->maximum() - horizontalScrollBar()->value()
            : horizontalScrollBar()->value());
}

/*!
  \reimp
*/
int QListView::verticalOffset() const
{
    // ## split into static and dynamic
    Q_D(const QListView);
    if (verticalScrollMode() == QAbstractItemView::ScrollPerItem && d->viewMode == ListMode) {
        if (d->isWrapping()) {
            if (d->flow == LeftToRight && !d->staticListView->segmentPositions.isEmpty()) {
                int value = verticalScrollBar()->value();
                if (value >= d->staticListView->segmentPositions.count()) {
                    //qWarning("QListView: Vertical scroll bar is out of bounds");
                    return 0;
                }
                return d->staticListView->segmentPositions.at(value);
            }
        } else {
            if (d->flow == TopToBottom && !d->staticListView->flowPositions.isEmpty()) {
                int value = verticalScrollBar()->value();
                if (value >= d->staticListView->flowPositions.count()) {
                    //qWarning("QListView: Vertical scroll bar is out of bounds");
                    return 0;
                }
                return d->staticListView->flowPositions.at(value) - d->spacing();
            }
        }
    }
    return verticalScrollBar()->value();
}

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

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

    QRect rect = rectForIndex(current);
    if (rect.isEmpty()) {
        return d->model->index(0, 0, d->root);
    }
    if (d->gridSize().isValid()) rect.setSize(d->gridSize());

    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 d->model->index(d->batchStartRow() - 1, d->column, d->root);
#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 d->model->index(0, d->column, d->root);
#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 d->model->index(0, d->column, d->root);
    case MoveEnd:
        return d->model->index(d->batchStartRow() - 1, d->column, d->root);}

    return current;
}

/*!
    Returns the rectangle of the item at position \a index in the
    model. The rectangle is in contents coordinates.

    \sa visualRect()
*/
QRect QListView::rectForIndex(const QModelIndex &index) const
{
    Q_D(const QListView);
    if (!d->isIndexValid(index)
        || index.parent() != d->root
        || 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
        || !d->isIndexValid(index)
        || index.parent() != d->root
        || index.column() != d->column)
        return;

    d->executePostedLayout();
    if (index.row() >= d->dynamicListView->items.count())
        return;
    const QSize oldContents = d->contentsSize();
    d->setDirtyRegion(visualRect(index)); // update old position
    d->dynamicListView->moveItem(index.row(), position);
    d->setDirtyRegion(visualRect(index)); // update new position

    if (d->contentsSize() != oldContents)
        updateGeometries(); // update the scroll bars
}

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

    // if we are wrapping, we can only selecte inside the contents rectangle
    if (d->wrap && !QRect(QPoint(0, 0), d->contentsSize()).intersects(rect))
        return;

    QItemSelection selection;

    if (rect.width() == 1 && rect.height() == 1) {
        d->intersectingSet(rect.translated(horizontalOffset(), verticalOffset()));
        QModelIndex tl;
        if (!d->intersectVector.isEmpty())
            tl = d->intersectVector.last(); // special case for mouse press; only select the top item
        if (tl.isValid())
            selection.select(tl, tl);
    } else {
        if (state() == DragSelectingState) { // visual selection mode (rubberband selection)
            selection = d->selection(rect.translated(horizontalOffset(), verticalOffset()));
        } else { // logical selection mode (key and mouse click selection)

            QModelIndex tl, br;
            // get the first item
            const QRect topLeft(rect.left() + horizontalOffset(), rect.top() + verticalOffset(), 1, 1);
            d->intersectingSet(topLeft);
            if (!d->intersectVector.isEmpty())
                tl = d->intersectVector.last();
            // get the last item
            const QRect bottomRight(rect.right() + horizontalOffset(), rect.bottom() + verticalOffset(), 1, 1);
            d->intersectingSet(bottomRight);
            if (!d->intersectVector.isEmpty())
                br = d->intersectVector.last();

            // get the ranges
            if (tl.isValid() && br.isValid()) {
                QRect first = rectForIndex(tl);
                QRect last = rectForIndex(br);
                QRect middle;
                if (d->flow == TopToBottom) {
                    
                }
                if (d->flow == LeftToRight) {
                    QRect &top = first;
                    QRect &bottom = last;
                    // if bottom is above top, swap them
                    if (top.center().y() > bottom.center().y()) {
                        QRect tmp = top;
                        top = bottom;
                        bottom = tmp;
                    }
                    // if the rect are on differnet lines, expand
                    if (top.top() != bottom.top()) {
                        // top rectangle
                        if (isRightToLeft())
                            top.setLeft(0);
                        else
                            top.setRight(contentsSize().width());
                        // bottom rectangle
                        if (isRightToLeft())
                            bottom.setRight(contentsSize().width());
                        else
                            bottom.setLeft(0);
                    } else if (top.left() > bottom.right()) {
                        if (isRightToLeft())
                            bottom.setLeft(top.right());
                        else
                            bottom.setRight(top.left());
                    } else {
                        if (isRightToLeft())
                            top.setLeft(bottom.right());
                        else
                            top.setRight(bottom.left());
                    }
                    // middle rectangle
                    if (top.bottom() < bottom.top()) {
                        middle.setTop(top.bottom() + 1);
                        middle.setLeft(qMin(top.left(), bottom.left()));
                        middle.setBottom(bottom.top() - 1);
                        middle.setRight(qMax(top.right(), bottom.right()));
                    }
                } else {    // TopToBottom
                    QRect &left = first;
                    QRect &right = last;
                    if (left.center().x() > right.center().x())
                        qSwap(left, right);

                    int ch = contentsSize().height();
                    if (left.left() != right.left()) {
                        // left rectangle
                        if (isRightToLeft())
                            left.setTop(0);
                        else
                            left.setBottom(ch);

                        // top rectangle
                        if (isRightToLeft())
                            right.setBottom(ch);
                        else
                            right.setTop(0);
                        // only set middle if the 
                        middle.setTop(0);
                        middle.setBottom(ch);
                        middle.setLeft(left.right() + 1);
                        middle.setRight(right.left() - 1);
                    } else if (left.bottom() < right.top()) {
                        left.setBottom(right.top() - 1);