qtextcursor.cpp

奇趣公司比较新的qt/emd版本

        return -1;
    return qMax(d->position, d->adjusted_anchor);
}

static void getText(QString &text, QTextDocumentPrivate *priv, const QString &docText, int pos, int end)
{
    while (pos < end) {
        QTextDocumentPrivate::FragmentIterator fragIt = priv->find(pos);
        const QTextFragmentData * const frag = fragIt.value();

        const int offsetInFragment = qMax(0, pos - fragIt.position());
        const int len = qMin(int(frag->size - offsetInFragment), end - pos);

        text += QString(docText.constData() + frag->stringPosition + offsetInFragment, len);
        pos += len;
    }
}

/*!
    Returns the current selection's text (which may be empty). This
    only returns the text, with no rich text formatting information.
    If you want a document fragment (i.e. formatted rich text) use
    selection() instead.

    \note If the selection obtained from an editor spans a line break,
    the text will contain a Unicode U+2029 paragraph separator character
    instead of a newline \c{\n} character. Use QString::replace() to
    replace these characters with newlines.
*/
QString QTextCursor::selectedText() const
{
    if (!d || !d->priv || d->position == d->anchor)
        return QString();

    const QString docText = d->priv->buffer();
    QString text;

    QTextTable *table = d->complexSelectionTable();
    if (table) {
        int row_start, col_start, num_rows, num_cols;
        selectedTableCells(&row_start, &num_rows, &col_start, &num_cols);

        Q_ASSERT(row_start != -1);
        for (int r = row_start; r < row_start + num_rows; ++r) {
            for (int c = col_start; c < col_start + num_cols; ++c) {
                QTextTableCell cell = table->cellAt(r, c);
                int rspan = cell.rowSpan();
                int cspan = cell.columnSpan();
                if (rspan != 1) {
                    int cr = cell.row();
                    if (cr != r)
                        continue;
                }
                if (cspan != 1) {
                    int cc = cell.column();
                    if (cc != c)
                        continue;
                }

                getText(text, d->priv, docText, cell.firstPosition(), cell.lastPosition());
            }
        }
    } else {
        getText(text, d->priv, docText, selectionStart(), selectionEnd());
    }

    return text;
}

/*!
    Returns the current selection (which may be empty) with all its
    formatting information. If you just want the selected text (i.e.
    plain text) use selectedText() instead.

    \note Unlike QTextDocumentFragment::toPlainText(),
    selectedText() may include special unicode characters such as
    QChar::ParagraphSeparator.

    \sa QTextDocumentFragment::toPlainText()
*/
QTextDocumentFragment QTextCursor::selection() const
{
    return QTextDocumentFragment(*this);
}

/*!
    Returns the block that contains the cursor.
*/
QTextBlock QTextCursor::block() const
{
    if (!d || !d->priv)
        return QTextBlock();
    return d->block();
}

/*!
    Returns the block format of the block the cursor is in.

    \sa setBlockFormat() charFormat()
 */
QTextBlockFormat QTextCursor::blockFormat() const
{
    if (!d || !d->priv)
        return QTextBlockFormat();

    return d->block().blockFormat();
}

/*!
    Sets the block format of the current block (or all blocks that
    are contained in the selection) to \a format.

    \sa blockFormat(), mergeBlockFormat()
*/
void QTextCursor::setBlockFormat(const QTextBlockFormat &format)
{
    if (!d || !d->priv)
        return;

    d->setBlockFormat(format, QTextDocumentPrivate::SetFormat);
}

/*!
    Modifies the block format of the current block (or all blocks that
    are contained in the selection) with the block format specified by
    \a modifier.

    \sa setBlockFormat(), blockFormat()
*/
void QTextCursor::mergeBlockFormat(const QTextBlockFormat &modifier)
{
    if (!d || !d->priv)
        return;

    d->setBlockFormat(modifier, QTextDocumentPrivate::MergeFormat);
}

/*!
    Returns the block character format of the block the cursor is in.

    The block char format is the format used when inserting text at the
    beginning of an empty block.

    \sa setBlockCharFormat()
 */
QTextCharFormat QTextCursor::blockCharFormat() const
{
    if (!d || !d->priv)
        return QTextCharFormat();

    return d->block().charFormat();
}

/*!
    Sets the block char format of the current block (or all blocks that
    are contained in the selection) to \a format.

    \sa blockCharFormat()
*/
void QTextCursor::setBlockCharFormat(const QTextCharFormat &format)
{
    if (!d || !d->priv)
        return;

    d->setBlockCharFormat(format, QTextDocumentPrivate::SetFormatAndPreserveObjectIndices);
}

/*!
    Modifies the block char format of the current block (or all blocks that
    are contained in the selection) with the block format specified by
    \a modifier.

    \sa setBlockCharFormat()
*/
void QTextCursor::mergeBlockCharFormat(const QTextCharFormat &modifier)
{
    if (!d || !d->priv)
        return;

    d->setBlockCharFormat(modifier, QTextDocumentPrivate::MergeFormat);
}

/*!
    Returns the format of the character immediately before the cursor position(). If the cursor is
    positioned at the beginning of a text block that is not empty then the format of the character
    immediately after the cursor is returned.

    \sa insertText(), blockFormat()
 */
QTextCharFormat QTextCursor::charFormat() const
{
    if (!d || !d->priv)
        return QTextCharFormat();

    int idx = d->currentCharFormat;
    if (idx == -1) {
        QTextBlock block = d->block();

        int pos;
        if (d->position == block.position()
            && block.length() > 1)
            pos = d->position;
        else
            pos = d->position - 1;

        if (pos == -1) {
            idx = d->priv->blockCharFormatIndex(d->priv->blockMap().firstNode());
        } else {
            Q_ASSERT(pos >= 0 && pos < d->priv->length());

            QTextDocumentPrivate::FragmentIterator it = d->priv->find(pos);
            Q_ASSERT(!it.atEnd());
            idx = it.value()->format;
        }
    }

    QTextCharFormat cfmt = d->priv->formatCollection()->charFormat(idx);
    cfmt.clearProperty(QTextFormat::ObjectIndex);

    Q_ASSERT(cfmt.isValid());
    return cfmt;
}

/*!
    Sets the cursor's current character format to the given \a
    format. If the cursor has a selection, the given \a format is
    applied to the current selection.

    \sa hasSelection(), mergeCharFormat()
*/
void QTextCursor::setCharFormat(const QTextCharFormat &format)
{
    if (!d || !d->priv)
        return;
    if (d->position == d->anchor) {
        d->currentCharFormat = d->priv->formatCollection()->indexForFormat(format);
        return;
    }
    d->setCharFormat(format, QTextDocumentPrivate::SetFormatAndPreserveObjectIndices);
}

/*!
    Merges the cursor's current character format with the properties
    described by format \a modifier. If the cursor has a selection,
    this function applies all the properties set in \a modifier to all
    the character formats that are part of the selection.

    \sa hasSelection(), setCharFormat()
*/
void QTextCursor::mergeCharFormat(const QTextCharFormat &modifier)
{
    if (!d || !d->priv)
        return;
    if (d->position == d->anchor) {
        QTextCharFormat format = charFormat();
        format.merge(modifier);
        d->currentCharFormat = d->priv->formatCollection()->indexForFormat(format);
        return;
    }

    d->setCharFormat(modifier, QTextDocumentPrivate::MergeFormat);
}

/*!
    Returns true if the cursor is at the start of a block; otherwise
    returns false.

    \sa atBlockEnd(), atStart()
*/
bool QTextCursor::atBlockStart() const
{
    if (!d || !d->priv)
        return false;

    return d->position == d->block().position();
}

/*!
    Returns true if the cursor is at the end of a block; otherwise
    returns false.

    \sa atBlockStart(), atEnd()
*/
bool QTextCursor::atBlockEnd() const
{
    if (!d || !d->priv)
        return false;

    return d->position == d->block().position() + d->block().length() - 1;
}

/*!
    Returns true if the cursor is at the start of the document;
    otherwise returns false.

    \sa atBlockStart(), atEnd()
*/
bool QTextCursor::atStart() const
{
    if (!d || !d->priv)
        return false;

    return d->position == 0;
}

/*!
    Returns true if the cursor is at the end of the document;
    otherwise returns false.

    \sa atStart(), atBlockEnd()
*/
bool QTextCursor::atEnd() const
{
    if (!d || !d->priv)
        return false;

    return d->position == d->priv->length() - 1;
}

/*!
    Inserts a new empty block at the cursor position() with the
    current blockFormat() and charFormat().

    \sa setBlockFormat()
*/
void QTextCursor::insertBlock()
{
    insertBlock(blockFormat());
}

/*!
    \overload

    Inserts a new empty block at the cursor position() with block
    format \a format and the current charFormat() as block char format.

    \sa setBlockFormat()
*/
void QTextCursor::insertBlock(const QTextBlockFormat &format)
{
    QTextCharFormat charFmt = charFormat();
    charFmt.clearProperty(QTextFormat::ObjectType);
    insertBlock(format, charFmt);
}

/*!
    \fn void QTextCursor::insertBlock(const QTextBlockFormat &format, const QTextCharFormat &charFormat)
    \overload

    Inserts a new empty block at the cursor position() with block
    format \a format and \a charFormat as block char format.

    \sa setBlockFormat()
*/
void QTextCursor::insertBlock(const QTextBlockFormat &format, const QTextCharFormat &_charFormat)
{
    if (!d || !d->priv)
        return;

    QTextCharFormat charFormat = _charFormat;
    charFormat.clearProperty(QTextFormat::ObjectIndex);

    d->priv->beginEditBlock();
    d->remove();
    d->insertBlock(format, charFormat);
    d->priv->endEditBlock();
}

/*!
    Inserts a new block at the current position and makes it the first
    list item of a newly created list with the given \a format. Returns
    the created list.

    \sa currentList() createList() insertBlock()
 */
QTextList *QTextCursor::insertList(const QTextListFormat &format)
{
    insertBlock();
    return createList(format);
}

/*!
    \overload

    Inserts a new block at the current position and makes it the first
    list item of a newly created list with the given \a style. Returns
    the created list.

    \sa currentList(), createList(), insertBlock()
 */
QTextList *QTextCursor::insertList(QTextListFormat::Style style)
{
    insertBlock();
    return createList(style);
}

/*!
    Creates and returns a new list with the given \a format, and makes the
    current paragraph the cursor is in the first list item.

    \sa insertList() currentList()
 */
QTextList *QTextCursor::createList(const QTextListFormat &format)
{
    if (!d || !d->priv)
        return 0;

    QTextList *list = static_cast<QTextList *>(d->priv->createObject(format));
    QTextBlockFormat modifier;
    modifier.setObjectIndex(list->objectIndex());
    mergeBlockFormat(modifier);
    return list;
}

/*!
    \overload

    Creates and returns a new list with the given \a style, making the
    cursor's current paragraph the first list item.

    The style to be used is defined by the QTextListFormat::Style enum.

    \sa insertList() currentList()
 */
QTextList *QTextCursor::createList(QTextListFormat::Style style)
{
    QTextListFormat fmt;
    fmt.setStyle(style);
    return createList(fmt);
}

/*!
    Returns the current list if the cursor position() is inside a
    block that is part of a list; otherwise returns 0.

    \sa insertList() createList()
 */
QTextList *QTextCursor::currentList() const
{
    if (!d || !d->priv)