qtextformat.cpp

奇趣公司比较新的qt/emd版本

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#include "qtextformat.h"
#include "qtextformat_p.h"

#include <qvariant.h>
#include <qdatastream.h>
#include <qdebug.h>
#include <qmap.h>
#include <qhash.h>

/*!
    \class QTextLength
    \brief The QTextLength class encapsulates the different types of length
    used in a QTextDocument.

    \ingroup text

    When we specify a value for the length of an element in a text document,
    we often need to provide some other information so that the length is
    used in the way we expect. For example, when we specify a table width,
    the value can represent a fixed number of pixels, or it can be a percentage
    value. This information changes both the meaning of the value and the way
    it is used.

    Generally, this class is used to specify table widths. These can be
    specified either as a fixed amount of pixels, as a percentage of the
    containing frame's width, or by a variable width that allows it to take
    up just the space it requires.

    \sa QTextTable
*/

/*!
    \fn explicit QTextLength::QTextLength()

    Constructs a new length object which represents a variable size.
*/

/*!
    \fn QTextLength::QTextLength(Type type, qreal value)

    Constructs a new length object of the given \a type and \a value.
*/

/*!
    \fn Type QTextLength::type() const

    Returns the type of length.

    \sa QTextLength::Type
*/

/*!
    \fn qreal QTextLength::value(qreal maximumLength) const

    Returns the effective length, constrained by the type of the length object
    and the specified \a maximumLength.

    \sa type()
*/

/*!
    \fn qreal QTextLength::rawValue() const

    Returns the constraint value that is specific for the type of the length.
    If the length is QTextLength::PercentageLength then the raw value is in
    percent, in the range of 0 to 100. If the length is QTextLength::FixedLength
    then that fixed amount is returned. For variable lengths, zero is returned.
*/

/*!
    \fn bool QTextLength::operator==(const QTextLength &other) const

    Returns true if this text length is the same as the \a other text
    length.
*/

/*!
    \fn bool QTextLength::operator!=(const QTextLength &other) const

    Returns true if this text length is different from the \a other text
    length.
*/

/*!
    \enum QTextLength::Type

    \value VariableLength
    \value FixedLength
    \value PercentageLength
*/

/*!
   Returns the text length as a QVariant
*/
QTextLength::operator QVariant() const
{
    return QVariant(QVariant::TextLength, this);
}

QDataStream &operator<<(QDataStream &stream, const QTextLength &length)
{
    return stream << qint32(length.lengthType) << double(length.fixedValueOrPercentage);
}

QDataStream &operator>>(QDataStream &stream, QTextLength &length)
{
    qint32 type;
    double fixedValueOrPercentage;
    stream >> type >> fixedValueOrPercentage;
    length.fixedValueOrPercentage = fixedValueOrPercentage;
    length.lengthType = QTextLength::Type(type);
    return stream;
}

class QTextFormatPrivate : public QSharedData
{
public:
    QTextFormatPrivate() : hashDirty(true), fontDirty(true), hashValue(0) {}

    struct Property
    {
        inline Property(qint32 k, const QVariant &v) : key(k), value(v) {}
        inline Property() {}

        qint32 key;
        QVariant value;

        inline bool operator==(const Property &other) const
        { return key == other.key && value == other.value; }
        inline bool operator!=(const Property &other) const
        { return key != other.key || value != other.value; }
    };

    inline uint hash() const
    {
        if (!hashDirty)
            return hashValue;
        return recalcHash();
    }

    inline bool operator==(const QTextFormatPrivate &rhs) const {
        if (hash() != rhs.hash())
            return false;

        return props == rhs.props;
    }

    inline void insertProperty(qint32 key, const QVariant &value)
    {
        hashDirty = true;
        fontDirty = true;
        for (int i = 0; i < props.count(); ++i)
            if (props.at(i).key == key) {
                props[i].value = value;
                return;
            }
        props.append(Property(key, value));
    }

    inline void clearProperty(qint32 key)
    {
        hashDirty = true;
        fontDirty = true;
        for (int i = 0; i < props.count(); ++i)
            if (props.at(i).key == key) {
                props.remove(i);
                return;
            }
    }

    inline int propertyIndex(qint32 key) const
    {
        for (int i = 0; i < props.count(); ++i)
            if (props.at(i).key == key)
                return i;
        return -1;
    }

    inline QVariant property(qint32 key) const
    {
        const int idx = propertyIndex(key);
        if (idx < 0)
            return QVariant();
        return props.at(idx).value;
    }

    inline bool hasProperty(qint32 key) const
    { return propertyIndex(key) != -1; }

    void resolveFont(const QFont &defaultFont);

    inline const QFont &font() const {
        if (fontDirty)
            recalcFont();
        return fnt;
    }

    QVector<Property> props;
private:

    uint recalcHash() const;
    void recalcFont() const;

    mutable bool hashDirty;
    mutable bool fontDirty;
    mutable uint hashValue;
    mutable QFont fnt;

    friend QDataStream &operator<<(QDataStream &, const QTextFormat &);
    friend QDataStream &operator>>(QDataStream &, QTextFormat &);
};

static uint variantHash(const QVariant &variant)
{
    switch (variant.type()) {
    case QVariant::Invalid: return 0;
    case QVariant::Bool: return variant.toBool();
    case QVariant::Int: return variant.toInt();
    case QVariant::Double: return static_cast<int>(variant.toDouble());
    case QVariant::String: return qHash(variant.toString());
    case QVariant::Color: return qHash(qvariant_cast<QColor>(variant).rgb());
    default: break;
    }
    return qHash(variant.typeName());
}

uint QTextFormatPrivate::recalcHash() const
{
    hashValue = 0;
    for (QVector<Property>::ConstIterator it = props.constBegin(); it != props.constEnd(); ++it)
        hashValue += (it->key << 16) + variantHash(it->value);

    hashDirty = false;

    return hashValue;
}

void QTextFormatPrivate::resolveFont(const QFont &defaultFont)
{
    recalcFont();
    const uint oldMask = fnt.resolve();
    fnt = fnt.resolve(defaultFont);

    if (hasProperty(QTextFormat::FontSizeAdjustment)) {
        const qreal scaleFactors[7] = {0.7, 0.8, 1.0, 1.2, 1.5, 2, 2.4};

        const int htmlFontSize = qBound(0, property(QTextFormat::FontSizeAdjustment).toInt() + 3 - 1, 6);


        if (defaultFont.pointSize() <= 0) {
            qreal pixelSize = scaleFactors[htmlFontSize] * defaultFont.pixelSize();
            fnt.setPixelSize(qRound(pixelSize));
        } else {
            qreal pointSize = scaleFactors[htmlFontSize] * defaultFont.pointSizeF();
            fnt.setPointSizeF(pointSize);
        }
    }

    fnt.resolve(oldMask);
}

void QTextFormatPrivate::recalcFont() const
{
    // update cached font as well
    QFont f;

    for (int i = 0; i < props.count(); ++i) {
        switch (props.at(i).key) {
            case QTextFormat::FontFamily:
                f.setFamily(props.at(i).value.toString());
                break;
            case QTextFormat::FontPointSize:
                f.setPointSizeF(props.at(i).value.toDouble());
                break;
            case  QTextFormat::FontPixelSize:
                f.setPixelSize(props.at(i).value.toInt());
                break;
            case QTextFormat::FontWeight: {
                int weight = props.at(i).value.toInt();
                if (weight == 0) weight = QFont::Normal;
                f.setWeight(weight);
                break; }
            case QTextFormat::FontItalic:
                f.setItalic(props.at(i).value.toBool());
                break;
            case QTextFormat::FontUnderline:
                if (! hasProperty(QTextFormat::TextUnderlineStyle)) // don't use the old one if the new one is there.
                    f.setUnderline(props.at(i).value.toBool());
                break;
            case QTextFormat::TextUnderlineStyle:
                f.setUnderline(static_cast<QTextCharFormat::UnderlineStyle>(props.at(i).value.toInt()) == QTextCharFormat::SingleUnderline);
                break;
            case QTextFormat::FontOverline:
                f.setOverline(props.at(i).value.toBool());
                break;
            case QTextFormat::FontStrikeOut:
                f.setStrikeOut(props.at(i).value.toBool());
                break;
            case QTextFormat::FontFixedPitch:
                f.setFixedPitch(props.at(i).value.toBool());
                break;
            default:
                break;
            }
    }
    fnt = f;
    fontDirty = false;
}

Q_GUI_EXPORT QDataStream &operator<<(QDataStream &stream, const QTextFormat &fmt)
{
    stream << fmt.format_type << fmt.properties();
    return stream;
}

Q_GUI_EXPORT QDataStream &operator>>(QDataStream &stream, QTextFormat &fmt)
{
    QMap<qint32, QVariant> properties;
    stream >> fmt.format_type >> properties;

    // QTextFormat's default constructor doesn't allocate the private structure, so
    // we have to do this, in case fmt is a default constructed value.
    if(!fmt.d)
        fmt.d = new QTextFormatPrivate();

    for (QMap<qint32, QVariant>::ConstIterator it = properties.constBegin();
         it != properties.constEnd(); ++it)
        fmt.d->insertProperty(it.key(), it.value());

    return stream;
}

/*!
    \class QTextFormat
    \brief The QTextFormat class provides formatting information for a
    QTextDocument.

    \ingroup text
    \ingroup shared

    A QTextFormat is a generic class used for describing the format of
    parts of a QTextDocument. The derived classes QTextCharFormat,
    QTextBlockFormat, QTextListFormat, and QTextTableFormat are usually
    more useful, and describe the formatting that is applied to
    specific parts of the document.

    A format has a \c FormatType which specifies the kinds of thing it
    can format; e.g. a block of text, a list, a table, etc. A format
    also has various properties (some specific to particular format
    types), as described by the Property enum. Every property has a
    corresponding Property.

    The format type is given by type(), and the format can be tested
    with isCharFormat(), isBlockFormat(), isListFormat(),
    isTableFormat(), isFrameFormat(), and isImageFormat(). If the
    type is determined, it can be retrieved with toCharFormat(),
    toBlockFormat(), toListFormat(), toTableFormat(), toFrameFormat(),
    and toImageFormat().

    A format's properties can be set with the setProperty() functions,
    and retrieved with boolProperty(), intProperty(), doubleProperty(),
    and stringProperty() as appropriate. All the property IDs used in
    the format can be retrieved with allPropertyIds(). One format can
    be merged into another using merge().

    A format's object index can be set with setObjectIndex(), and
    retrieved with objectIndex(). These methods can be used to
    associate the format with a QTextObject. It is used to represent
    lists, frames, and tables inside the document.

    \sa {Text Processing Classes}
*/

/*!
    \enum QTextFormat::FormatType

    \value InvalidFormat
    \value BlockFormat
    \value CharFormat
    \value ListFormat
    \value TableFormat
    \value FrameFormat

    \value UserFormat
*/

/*!
    \enum QTextFormat::Property

    \value ObjectIndex

    Paragraph and character properties

    \value CssFloat
    \value LayoutDirection  The layout direction of the text in the document
                            (Qt::LayoutDirection).

    \value OutlinePen
    \value ForegroundBrush
    \value BackgroundBrush

    Paragraph properties

    \value BlockAlignment
    \value BlockTopMargin
    \value BlockBottomMargin
    \value BlockLeftMargin
    \value BlockRightMargin
    \value TextIndent
    \value BlockIndent
    \value BlockNonBreakableLines
    \value BlockTrailingHorizontalRulerWidth

    Character properties

    \value FontFamily
    \value FontPointSize
    \omitvalue FontSizeAdjustment
    \value FontSizeIncrement
    \value FontWeight
    \value FontItalic
    \value FontUnderline \e{This property has been deprecated.} Use QTextFormat::TextUnderlineStyle instead.
    \value FontOverline 
    \value FontStrikeOut
    \value FontFixedPitch
    \value FontPixelSize

    \value TextUnderlineColor
    \value TextVerticalAlignment
    \value TextOutline
    \value TextUnderlineStyle
    \value TextToolTip Specifies the (optional) tool tip to be displayed for a fragment of text.

    \value IsAnchor
    \value AnchorHref
    \value AnchorName

    \value ObjectType

    List properties

    \value ListStyle
    \value ListIndent

    Table and frame properties

    \value FrameBorder
    \value FrameBorderBrush
    \value FrameBorderStyle
    \value FrameBottomMargin
    \value FrameHeight
    \value FrameLeftMargin 
    \value FrameMargin
    \value FramePadding
    \value FrameRightMargin
    \value FrameTopMargin
    \value FrameWidth
    \value TableCellSpacing
    \value TableCellPadding
    \value TableColumns
    \value TableColumnWidthConstraints
    \value TableHeaderRowCount

    Table cell properties

    \value TableCellRowSpan
    \value TableCellColumnSpan

    Image properties

    \value ImageName
    \value ImageWidth
    \value ImageHeight

    Selection properties

    \value FullWidthSelection

    Page break properties

    \value PageBreakPolicy