qtextdocument.cpp

奇趣公司比较新的qt/emd版本

/*!
    \fn QTextDocument::modificationChanged(bool changed)

    This signal is emitted whenever the content of the document
    changes in a way that affects the modification state. If \a
    changed is true, the document has been modified; otherwise it is
    false.

    For example, calling setModified(false) on a document and then
    inserting text causes the signal to get emitted. If you undo that
    operation, causing the document to return to its original
    unmodified state, the signal will get emitted again.
*/

/*!
    \property QTextDocument::modified
    \brief whether the document has been modified by the user

    \sa modificationChanged()
*/

bool QTextDocument::isModified() const
{
    return docHandle()->isModified();
}

void QTextDocument::setModified(bool m)
{
    docHandle()->setModified(m);
}

#ifndef QT_NO_PRINTER
static void printPage(int index, QPainter *painter, const QTextDocument *doc, const QRectF &body, const QPointF &pageNumberPos)
{
    painter->save();
    painter->translate(body.left(), body.top() - (index - 1) * body.height());
    QRectF view(0, (index - 1) * body.height(), body.width(), body.height());

    QAbstractTextDocumentLayout *layout = doc->documentLayout();
    QAbstractTextDocumentLayout::PaintContext ctx;

    painter->setClipRect(view);
    ctx.clip = view;

    // don't use the system palette text as default text color, on HP/UX
    // for example that's white, and white text on white paper doesn't
    // look that nice
    ctx.palette.setColor(QPalette::Text, Qt::black);

    layout->draw(painter, ctx);

    if (!pageNumberPos.isNull()) {
        painter->setClipping(false);
        painter->setFont(QFont(doc->defaultFont()));
        const QString pageString = QString::number(index);

        painter->drawText(qRound(pageNumberPos.x() - painter->fontMetrics().width(pageString)),
                          qRound(pageNumberPos.y() + view.top()),
                          pageString);
    }

    painter->restore();
}

/*!
    Prints the document to the given \a printer. The QPrinter must be
    set up before being used with this function.

    This is only a convenience method to print the whole document to the printer.

    If the document is already paginated through a specified height in the pageSize()
    property it is printed as-is.

    If the document is not paginated, like for example a document used in a QTextEdit,
    then a temporary copy of the document is created and the copy is broken into
    multiple pages according to the size of the QPrinter's paperRect(). By default
    a 2 cm margin is set around the document contents. In addition the current page
    number is printed at the bottom of each page.

    Note that QPrinter::Selection is not supported as print range with this function since
    the selection is a property of QTextCursor. If you have a QTextEdit associated with
    your QTextDocument then you can use QTextEdit's print() function because QTextEdit has
    access to the user's selection.

    \sa QTextEdit::print()
*/

void QTextDocument::print(QPrinter *printer) const
{
    Q_D(const QTextDocument);

    if (!d->title.isEmpty())
        printer->setDocName(d->title);

    QPainter p(printer);

    // Check that there is a valid device to print to.
    if (!p.isActive())
        return;

    const QTextDocument *doc = this;
    QTextDocument *clonedDoc = 0;
    (void)doc->documentLayout(); // make sure that there is a layout

    QRectF body = QRectF(QPointF(0, 0), d->pageSize);
    QPointF pageNumberPos;

    if (d->pageSize.isValid() && !d->pageSize.isNull()
        && d->pageSize.height() != INT_MAX) {
        extern int qt_defaultDpi();

        qreal sourceDpiX = qt_defaultDpi();
        qreal sourceDpiY = sourceDpiX;

        QPaintDevice *dev = doc->documentLayout()->paintDevice();
        if (dev) {
            sourceDpiX = dev->logicalDpiX();
            sourceDpiY = dev->logicalDpiY();
        }

        const qreal dpiScaleX = qreal(printer->logicalDpiX()) / sourceDpiX;
        const qreal dpiScaleY = qreal(printer->logicalDpiY()) / sourceDpiY;

        // scale to dpi
        p.scale(dpiScaleX, dpiScaleY);

        QSizeF scaledPageSize = d->pageSize;
        scaledPageSize.rwidth() *= dpiScaleX;
        scaledPageSize.rheight() *= dpiScaleY;

        const QSizeF printerPageSize(printer->pageRect().size());

        // scale to page
        p.scale(printerPageSize.width() / scaledPageSize.width(),
                printerPageSize.height() / scaledPageSize.height());
    } else {
        doc = clone(const_cast<QTextDocument *>(this));
        clonedDoc = const_cast<QTextDocument *>(doc);

        QAbstractTextDocumentLayout *layout = doc->documentLayout();
        layout->setPaintDevice(p.device());

        const int dpiy = p.device()->logicalDpiY();

        const int margin = (int) ((2/2.54)*dpiy); // 2 cm margins
        QTextFrameFormat fmt = doc->rootFrame()->frameFormat();
        fmt.setMargin(margin);
        doc->rootFrame()->setFrameFormat(fmt);

        body = QRectF(0, 0, p.device()->width(), p.device()->height());
        pageNumberPos = QPointF(body.width() - margin,
                                body.height() - margin
                                + QFontMetrics(doc->defaultFont(), p.device()).ascent()
                                + 5 * p.device()->logicalDpiY() / 72);

        clonedDoc->setPageSize(body.size());
    }

    int docCopies;
    int pageCopies;
    if (printer->collateCopies() == true){
        docCopies = 1;
        pageCopies = printer->numCopies();
    } else {
        docCopies = printer->numCopies();
        pageCopies = 1;
    }

    int fromPage = printer->fromPage();
    int toPage = printer->toPage();
    bool ascending = true;

    if (fromPage == 0 && toPage == 0) {
        fromPage = 1;
        toPage = doc->pageCount();
    }

    if (printer->pageOrder() == QPrinter::LastPageFirst) {
        int tmp = fromPage;
        fromPage = toPage;
        toPage = tmp;
        ascending = false;
    }

    for (int i = 0; i < docCopies; ++i) {

        int page = fromPage;
        while (true) {
            for (int j = 0; j < pageCopies; ++j) {
                if (printer->printerState() == QPrinter::Aborted
                    || printer->printerState() == QPrinter::Error)
                    goto UserCanceled;
                printPage(page, &p, doc, body, pageNumberPos);
                if (j < pageCopies - 1)
                    printer->newPage();
            }

            if (page == toPage)
                break;

            if (ascending)
                ++page;
            else
                --page;

            printer->newPage();
        }

        if ( i < docCopies - 1)
            printer->newPage();
    }

UserCanceled:
    delete clonedDoc;
}
#endif

/*!
    \enum QTextDocument::ResourceType

    This enum describes the types of resources that can be loaded by
    QTextDocument's loadResource() function.

    \value HtmlResource  The resource contains HTML.
    \value ImageResource The resource contains image data.
                         Currently supported data types are QVariant::Pixmap and
                         QVariant::Image. If the corresponding variant is of type
                         QVariant::ByteArray then Qt attempts to load the image using
                         QImage::loadFromData. QVariant::Icon is currently not supported.
                         The icon needs to be converted to one of the supported types first,
                         for example using QIcon::pixmap.
    \value StyleSheetResource The resource contains CSS.
    \value UserResource  The first available value for user defined
                         resource types.

    \sa loadResource()
*/

/*!
    Returns data of the specified \a type from the resource with the
    given \a name.

    This function is called by the rich text engine to request data that isn't
    directly stored by QTextDocument, but still associated with it. For example,
    images are referenced indirectly by the name attribute of a QTextImageFormat
    object.

    Resources are cached internally in the document. If a resource can
    not be found in the cache, loadResource is called to try to load
    the resource. loadResource should then use addResource to add the
    resource to the cache.
*/
QVariant QTextDocument::resource(int type, const QUrl &name) const
{
    Q_D(const QTextDocument);
    QVariant r = d->resources.value(name);
    if (!r.isValid()) {
        r = d->cachedResources.value(name);
        if (!r.isValid())
            r = const_cast<QTextDocument *>(this)->loadResource(type, name);
    }
    return r;
}

/*!
    Adds the resource \a resource to the resource cache, using \a
    type and \a name as identifiers. \a type should be a value from QTextDocument::ResourceType.
*/
void QTextDocument::addResource(int type, const QUrl &name, const QVariant &resource)
{
    Q_UNUSED(type);
    Q_D(QTextDocument);
    d->resources.insert(name, resource);
}

/*!
    Loads data of the specified \a type from the resource with the
    given \a name.

    This function is called by the rich text engine to request data that isn't
    directly stored by QTextDocument, but still associated with it. For example,
    images are referenced indirectly by the name attribute of a QTextImageFormat
    object.

    When called by Qt, \a type is one of the values of
    QTextDocument::ResourceType.

    If the QTextDocument is a child object of a QTextEdit, QTextBrowser,
    or a QTextDocument itself then the default implementation tries
    to retrieve the data from the parent.
*/
QVariant QTextDocument::loadResource(int type, const QUrl &name)
{
    Q_D(QTextDocument);
    QVariant r;
    if (QTextDocument *doc = qobject_cast<QTextDocument *>(parent()))
        r = doc->loadResource(type, name);
#ifndef QT_NO_TEXTEDIT
    else if (QTextEdit *edit = qobject_cast<QTextEdit *>(parent()))
        r = edit->loadResource(type, name);
#endif
#ifndef QT_NO_TEXTCONTROL
    else if (QTextControl *control = qobject_cast<QTextControl *>(parent()))
        r = control->loadResource(type, name);
#endif
    if (!r.isNull()) {
        if (type == ImageResource && r.type() == QVariant::ByteArray) {
            QPixmap pm;
            pm.loadFromData(r.toByteArray());
            if (!pm.isNull())
                r = pm;
        }
        d->cachedResources.insert(name, r);
    }
    return r;
}

static QTextFormat formatDifference(const QTextFormat &from, const QTextFormat &to)
{
    QTextFormat diff = to;

    const QMap<int, QVariant> props = to.properties();
    for (QMap<int, QVariant>::ConstIterator it = props.begin(), end = props.end();
         it != end; ++it)
        if (it.value() == from.property(it.key()))
            diff.clearProperty(it.key());

    return diff;
}

QTextHtmlExporter::QTextHtmlExporter(const QTextDocument *_doc)
    : doc(_doc), fragmentMarkers(false)
{
    const QFont defaultFont = doc->defaultFont();
    defaultCharFormat.setFont(defaultFont);
    // don't export those for the default font since we cannot turn them off with CSS
    defaultCharFormat.clearProperty(QTextFormat::FontUnderline);
    defaultCharFormat.clearProperty(QTextFormat::FontOverline);
    defaultCharFormat.clearProperty(QTextFormat::FontStrikeOut);
    defaultCharFormat.clearProperty(QTextFormat::TextUnderlineStyle);
}

/*!
    Returns the document in HTML format. The conversion may not be
    perfect, especially for complex documents, due to the limitations
    of HTML.
*/
QString QTextHtmlExporter::toHtml(const QByteArray &encoding, ExportMode mode)
{
    html = QLatin1String("<html><head><meta name=\"qrichtext\" content=\"1\" />");
    html.reserve(doc->docHandle()->length());

    fragmentMarkers = (mode == ExportFragment);

    if (!encoding.isEmpty())
        html += QString::fromLatin1("<meta http-equiv=\"Content-Type\" content=\"text/html; charset=%1\" />").arg(QString::fromAscii(encoding));

    QString title  = doc->metaInformation(QTextDocument::DocumentTitle);
    if (!title.isEmpty())
        html += QString::fromLatin1("<title>") + title + QString::fromLatin1("</title>");
    html += QLatin1String("<style type=\"text/css\">\n");
    html += QLatin1String("p, li { white-space: pre-wrap; }\n");
    html += QLatin1String("</style>");
    html += QLatin1String("</head><body");

    if (mode == ExportEntireDocument) {
        html += QLatin1String(" style=\"");

        emitFontFamily(defaultCharFormat.fontFamily());

        if (defaultCharFormat.hasProperty(QTextFormat::FontPointSize)) {
            html += QLatin1String(" font-size:");
            html += QString::number(defaultCharFormat.fontPointSize());
            html += QLatin1String("pt;");
        }

        html += QLatin1String(" font-weight:");
        html += QString::number(defaultCharFormat.fontWeight() * 8);
        html += QLatin1Char(';');

        html += QLatin1String(" font-style:");
        html += (defaultCharFormat.fontItalic() ? QLatin1String("italic") : QLatin1String("normal"));
        html += QLatin1Char(';');

        // do not set text-decoration on the default font since those values are /always/ propagated
        // and cannot be turned off with CSS

        html += QLatin1Char('\"');

        const QTextFrameFormat fmt = doc->rootFrame()->frameFormat();
        QBrush bg = fmt.background();
        if (bg != Qt::NoBrush)
            emitAttribute("bgcolor", bg.color().name());

    } else {
        defaultCharFormat = QTextCharFormat();
    }
    html += QLatin1Char('>');

    QTextFrameFormat rootFmt = doc->rootFrame()->frameFormat();
    rootFmt.clearProperty(QTextFormat::BackgroundBrush);

    QTextFrameFormat defaultFmt;
    defaultFmt.setMargin(DefaultRootFrameMargin);

    if (rootFmt == defaultFmt)
        emitFrame(doc->rootFrame()->begin());
    else
        emitTextFrame(doc->rootFrame());

    html += QLatin1String("</body></html>");
    return html;
}

void QTextHtmlExporter::emitAttribute(const char *attribute, const QString &value)
{
    html += QLatin1Char(' ');
    html += QLatin1String(attribute);
    html += QLatin1String("=\"");
    html += value;
    html += QLatin1Char('"');
}