source: trunk/src/gui/text/qtextlayout.h

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#ifndef QTEXTLAYOUT_H
#define QTEXTLAYOUT_H

#include <QtCore/qstring.h>
#include <QtCore/qnamespace.h>
#include <QtCore/qrect.h>
#include <QtCore/qvector.h>
#include <QtGui/qcolor.h>
#include <QtCore/qobject.h>
#include <QtGui/qevent.h>
#include <QtGui/qtextformat.h>

QT_BEGIN_HEADER

QT_BEGIN_NAMESPACE

QT_MODULE(Gui)

class QTextEngine;
class QFont;
class QRect;
class QRegion;
class QTextFormat;
class QPalette;
class QPainter;

class Q_GUI_EXPORT QTextInlineObject
{
public:
    QTextInlineObject(int i, QTextEngine *e) : itm(i), eng(e) {}
    inline QTextInlineObject() : itm(0), eng(0) {}
    inline bool isValid() const { return eng; }

    QRectF rect() const;
    qreal width() const;
    qreal ascent() const;
    qreal descent() const;
    qreal height() const;

    Qt::LayoutDirection textDirection() const;

    void setWidth(qreal w);
    void setAscent(qreal a);
    void setDescent(qreal d);

    int textPosition() const;

    int formatIndex() const;
    QTextFormat format() const;

private:
    friend class QTextLayout;
    int itm;
    QTextEngine *eng;
};

class QPaintDevice;
class QTextFormat;
class QTextLine;
class QTextBlock;
class QTextOption;

class Q_GUI_EXPORT QTextLayout
{
public:
    // does itemization
    QTextLayout();
    QTextLayout(const QString& text);
    QTextLayout(const QString& text, const QFont &font, QPaintDevice *paintdevice = 0);
    QTextLayout(const QTextBlock &b);
    ~QTextLayout();

    void setFont(const QFont &f);
    QFont font() const;

    void setText(const QString& string);
    QString text() const;

    void setTextOption(const QTextOption &option);
    QTextOption textOption() const;

    void setPreeditArea(int position, const QString &text);
    int preeditAreaPosition() const;
    QString preeditAreaText() const;

    struct FormatRange {
        int start;
        int length;
        QTextCharFormat format;
    };
    void setAdditionalFormats(const QList<FormatRange> &overrides);
    QList<FormatRange> additionalFormats() const;
    void clearAdditionalFormats();

    void setCacheEnabled(bool enable);
    bool cacheEnabled() const;

    void beginLayout();
    void endLayout();
    void clearLayout();

    QTextLine createLine();

    int lineCount() const;
    QTextLine lineAt(int i) const;
    QTextLine lineForTextPosition(int pos) const;

    enum CursorMode {
        SkipCharacters,