src/gui/widgets/qtextedit.cpp

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/****************************************************************************
**
** Copyright (C) 1992-2006 Trolltech ASA. All rights reserved.
**
** This file is part of the QtGui module of the Qt Toolkit.
**
** This file may be used under the terms of the GNU General Public
** License version 2.0 as published by the Free Software Foundation
** and appearing in the file LICENSE.GPL included in the packaging of
** this file.  Please review the following information to ensure GNU
** General Public Licensing requirements will be met:
** http://www.trolltech.com/products/qt/opensource.html
**
** If you are unsure which license is appropriate for your use, please
** review the following information:
** http://www.trolltech.com/products/qt/licensing.html or contact the
** sales department at sales@trolltech.com.
**
** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
**
****************************************************************************/

#include "qtextedit_p.h"
#include "qlineedit.h"
#include "qtextbrowser.h"

QStringList QTextEditMimeData::formats() const
{
    if (!fragment.isEmpty())
        return QStringList() << QString::fromLatin1("text/plain") << QString::fromLatin1("text/html");
    else
        return QMimeData::formats();
}

QVariant QTextEditMimeData::retrieveData(const QString &mimeType, QVariant::Type type) const
{
    if (!fragment.isEmpty())
        setup();
    return QMimeData::retrieveData(mimeType, type);
}

void QTextEditMimeData::setup() const
{
    QTextEditMimeData *that = const_cast<QTextEditMimeData *>(this);
    that->setData(QLatin1String("text/html"), fragment.toHtml("utf-8").toUtf8());
    that->setText(fragment.toPlainText());
    fragment = QTextDocumentFragment();
}

#ifndef QT_NO_TEXTEDIT

#include <qfont.h>
#include <qpainter.h>
#include <qevent.h>
#include <qdebug.h>
#include <qmime.h>
#include <qdrag.h>
#include <qclipboard.h>
#include <qmenu.h>
#include <qstyle.h>
#include <qtimer.h>
#include "private/qtextdocumentlayout_p.h"
#include "qtextdocument.h"
#include "private/qtextdocument_p.h"
#include "qtextlist.h"
#include "private/qtextcontrol_p.h"

#include <qtextformat.h>
#include <qdatetime.h>
#include <qapplication.h>
#include <limits.h>
#include <qtexttable.h>
#include <qvariant.h>

#include <qinputcontext.h>

class QTextEditControl : public QTextControl
{
public:
    inline QTextEditControl(QObject *parent) : QTextControl(parent) {}

    virtual QMimeData *createMimeDataFromSelection() const {
        QTextEdit *ed = qobject_cast<QTextEdit *>(parent());
        if (!ed)
            return QTextControl::createMimeDataFromSelection();
        return ed->createMimeDataFromSelection();
    }
    virtual bool canInsertFromMimeData(const QMimeData *source) const {
        QTextEdit *ed = qobject_cast<QTextEdit *>(parent());
        if (!ed)
            return QTextControl::canInsertFromMimeData(source);
        return ed->canInsertFromMimeData(source);
    }
    virtual void insertFromMimeData(const QMimeData *source) {
        QTextEdit *ed = qobject_cast<QTextEdit *>(parent());
        if (!ed)
            QTextControl::insertFromMimeData(source);
        else
            ed->insertFromMimeData(source);
    }
};

QTextEditPrivate::QTextEditPrivate()
    : control(0),
      autoFormatting(QTextEdit::AutoNone), tabChangesFocus(false),
      lineWrap(QTextEdit::WidgetWidth), lineWrapColumnOrWidth(0),
      textFormat(Qt::AutoText)
{
    ignoreAutomaticScrollbarAdjustment = false;
    preferRichText = false;
    showCursorOnInitialShow = true;
}

void QTextEditPrivate::createAutoBulletList()
{
    QTextCursor cursor = control->textCursor();
    cursor.beginEditBlock();

    QTextBlockFormat blockFmt = cursor.blockFormat();

    QTextListFormat listFmt;
    listFmt.setStyle(QTextListFormat::ListDisc);
    listFmt.setIndent(blockFmt.indent() + 1);

    blockFmt.setIndent(0);
    cursor.setBlockFormat(blockFmt);

    cursor.createList(listFmt);

    cursor.endEditBlock();
    control->setTextCursor(cursor);
}

void QTextEditPrivate::init(const QString &html)
{
    Q_Q(QTextEdit);
    control = new QTextEditControl(q);
    control->setPalette(q->palette());

    QObject::connect(control, SIGNAL(microFocusChanged()), q, SLOT(updateMicroFocus()));
    QObject::connect(control, SIGNAL(documentSizeChanged(QSizeF)), q, SLOT(_q_adjustScrollbars()));
    QObject::connect(control, SIGNAL(updateRequest(QRectF)), q, SLOT(_q_repaintContents(QRectF)));
    QObject::connect(control, SIGNAL(visibilityRequest(QRectF)), q, SLOT(_q_ensureVisible(QRectF)));
    QObject::connect(control, SIGNAL(currentCharFormatChanged(QTextCharFormat)),
                     q, SLOT(_q_currentCharFormatChanged(QTextCharFormat)));

    QObject::connect(control, SIGNAL(textChanged()), q, SIGNAL(textChanged()));
    QObject::connect(control, SIGNAL(undoAvailable(bool)), q, SIGNAL(undoAvailable(bool)));
    QObject::connect(control, SIGNAL(redoAvailable(bool)), q, SIGNAL(redoAvailable(bool)));
    QObject::connect(control, SIGNAL(copyAvailable(bool)), q, SIGNAL(copyAvailable(bool)));
    QObject::connect(control, SIGNAL(selectionChanged()), q, SIGNAL(selectionChanged()));
    QObject::connect(control, SIGNAL(cursorPositionChanged()), q, SIGNAL(cursorPositionChanged()));

    QTextDocument *doc = control->document();
    // set a null page size initially to avoid any relayouting until the textedit
    // is shown. relayoutDocument() will take care of setting the page size to the
    // viewport dimensions later.
    doc->setPageSize(QSize(0, 0));
    doc->documentLayout()->setPaintDevice(viewport);
    doc->setDefaultFont(q->font());

    if (!html.isEmpty())
        control->setHtml(html);

    hbar->setSingleStep(20);
    vbar->setSingleStep(20);

    viewport->setBackgroundRole(QPalette::Base);
    q->setAcceptDrops(true);
    q->setFocusPolicy(Qt::WheelFocus);
    q->setAttribute(Qt::WA_KeyCompression);
    q->setAttribute(Qt::WA_InputMethodEnabled);

#ifndef QT_NO_CURSOR
    viewport->setCursor(Qt::IBeamCursor);
#endif
}

void QTextEditPrivate::_q_repaintContents(const QRectF &contentsRect)
{
    if (!contentsRect.isValid()) {
        viewport->update();
        return;
    }
    const int xOffset = horizontalOffset();
    const int yOffset = verticalOffset();
    const QRectF visibleRect(xOffset, yOffset, viewport->width(), viewport->height());

    QRect r = contentsRect.intersected(visibleRect).toRect();
    if (r.isEmpty())
        return;

    r.translate(-xOffset, -yOffset);
    viewport->update(r);
}

void QTextEditPrivate::pageUpDown(QTextCursor::MoveOperation op, QTextCursor::MoveMode moveMode)
{
    QTextCursor cursor = control->textCursor();
    bool moved = false;
    qreal lastY = control->cursorRect(cursor).top();
    qreal distance = 0;
    // move using movePosition to keep the cursor's x
    do {
        qreal y = control->cursorRect(cursor).top();
        distance += qAbs(y - lastY);
        lastY = y;
        moved = cursor.movePosition(op, moveMode);
    } while (moved && distance < viewport->height());

    if (moved) {
        if (op == QTextCursor::Up) {
            cursor.movePosition(QTextCursor::Down, moveMode);
            vbar->triggerAction(QAbstractSlider::SliderPageStepSub);
        } else {
            cursor.movePosition(QTextCursor::Up, moveMode);
            vbar->triggerAction(QAbstractSlider::SliderPageStepAdd);
        }
    }
    control->setTextCursor(cursor);
}

#ifndef QT_NO_SCROLLBAR
void QTextEditPrivate::_q_adjustScrollbars()
{
    if (ignoreAutomaticScrollbarAdjustment)
        return;
    ignoreAutomaticScrollbarAdjustment = true; // avoid recursion, #106108

    QTextDocument *doc = control->document();
    QAbstractTextDocumentLayout *layout = doc->documentLayout();

    const QSize viewportSize = viewport->size();
    QSize docSize;

    if (QTextDocumentLayout *tlayout = qobject_cast<QTextDocumentLayout *>(layout)) {
        docSize = tlayout->dynamicDocumentSize().toSize();
        int percentageDone = tlayout->layoutStatus();
        // extrapolate height
        if (percentageDone > 0)
            docSize.setHeight(docSize.height() * 100 / percentageDone);
    } else {
        docSize = layout->documentSize().toSize();
    }

    hbar->setRange(0, docSize.width() - viewportSize.width());
    hbar->setPageStep(viewportSize.width());

    vbar->setRange(0, docSize.height() - viewportSize.height());
    vbar->setPageStep(viewportSize.height());

    // if we are in left-to-right mode widening the document due to
    // lazy layouting does not require a repaint. If in right-to-left
    // the scrollbar has the value zero and it visually has the maximum
    // value (it is visually at the right), then widening the document
    // keeps it at value zero but visually adjusts it to the new maximum
    // on the right, hence we need an update.
    if (q_func()->isRightToLeft())
        viewport->update();

    _q_showOrHideScrollBars();
    ignoreAutomaticScrollbarAdjustment = false;
}
#endif

// rect is in content coordinates
void QTextEditPrivate::_q_ensureVisible(const QRectF &_rect)
{
    const QRect rect = _rect.toRect();
    const int visibleWidth = viewport->width();
    const int visibleHeight = viewport->height();
    const bool rtl = q_func()->isRightToLeft();

    if (rect.x() < horizontalOffset()) {
        if (rtl)
            hbar->setValue(hbar->maximum() - rect.x());
        else
            hbar->setValue(rect.x());
    } else if (rect.x() + rect.width() > horizontalOffset() + visibleWidth) {
        if (rtl)
            hbar->setValue(hbar->maximum() - (rect.x() + rect.width() - visibleWidth));
        else
            hbar->setValue(rect.x() + rect.width() - visibleWidth);
    }

    if (rect.y() < verticalOffset())
        vbar->setValue(rect.y());
    else if (rect.y() + rect.height() > verticalOffset() + visibleHeight)
        vbar->setValue(rect.y() + rect.height() - visibleHeight);
}

void QTextEditPrivate::ensureViewportLayouted()
{
    QAbstractTextDocumentLayout *layout = control->document()->documentLayout();
    if (!layout)
        return;
    if (QTextDocumentLayout *tlayout = qobject_cast<QTextDocumentLayout *>(layout))
        tlayout->ensureLayouted(verticalOffset() + viewport->height());
}

#ifdef QT3_SUPPORT

#endif

QTextEdit::QTextEdit(QWidget *parent)
    : QAbstractScrollArea(*new QTextEditPrivate, parent)
{
    Q_D(QTextEdit);
    d->init();
}

QTextEdit::QTextEdit(QTextEditPrivate &dd, QWidget *parent)
    : QAbstractScrollArea(dd, parent)
{
    Q_D(QTextEdit);
    d->init();
}

QTextEdit::QTextEdit(const QString &text, QWidget *parent)
    : QAbstractScrollArea(*new QTextEditPrivate, parent)
{
    Q_D(QTextEdit);
    d->init(text);
}

#ifdef QT3_SUPPORT

QTextEdit::QTextEdit(QWidget *parent, const char *name)
    : QAbstractScrollArea(*new QTextEditPrivate, parent)
{
    Q_D(QTextEdit);
    d->init();
    setObjectName(QString::fromAscii(name));
}
#endif


QTextEdit::~QTextEdit()
{
}

qreal QTextEdit::fontPointSize() const
{
    Q_D(const QTextEdit);
    return d->control->textCursor().charFormat().fontPointSize();
}

QString QTextEdit::fontFamily() const
{
    Q_D(const QTextEdit);
    return d->control->textCursor().charFormat().fontFamily();
}

int QTextEdit::fontWeight() const
{
    Q_D(const QTextEdit);
    return d->control->textCursor().charFormat().fontWeight();
}

bool QTextEdit::fontUnderline() const
{
    Q_D(const QTextEdit);
    return d->control->textCursor().charFormat().fontUnderline();
}

bool QTextEdit::fontItalic() const
{
    Q_D(const QTextEdit);
    return d->control->textCursor().charFormat().fontItalic();
}

QColor QTextEdit::textColor() const
{
    Q_D(const QTextEdit);
    return d->control->textCursor().charFormat().foreground().color();
}

QFont QTextEdit::currentFont() const
{
    Q_D(const QTextEdit);
    return d->control->textCursor().charFormat().font();
}

void QTextEdit::setAlignment(Qt::Alignment a)
{
    Q_D(QTextEdit);
    QTextBlockFormat fmt;
    fmt.setAlignment(a);
    QTextCursor cursor = d->control->textCursor();
    cursor.mergeBlockFormat(fmt);
    d->control->setTextCursor(cursor);
}

Qt::Alignment QTextEdit::alignment() const
{
    Q_D(const QTextEdit);
    return d->control->textCursor().blockFormat().alignment();
}

void QTextEdit::setDocument(QTextDocument *document)
{
    Q_D(QTextEdit);
    d->control->setDocument(document);
    d->relayoutDocument();
}

QTextDocument *QTextEdit::document() const
{
    Q_D(const QTextEdit);
    return d->control->document();
}

void QTextEdit::setTextCursor(const QTextCursor &cursor)
{
    Q_D(QTextEdit);
    d->control->setTextCursor(cursor);
}

QTextCursor QTextEdit::textCursor() const
{
    Q_D(const QTextEdit);
    return d->control->textCursor();
}

void QTextEdit::setFontFamily(const QString &fontFamily)
{
    QTextCharFormat fmt;
    fmt.setFontFamily(fontFamily);
    mergeCurrentCharFormat(fmt);
}

void QTextEdit::setFontPointSize(qreal s)
{
    QTextCharFormat fmt;
    fmt.setFontPointSize(s);
    mergeCurrentCharFormat(fmt);
}

void QTextEdit::setFontWeight(int w)
{
    QTextCharFormat fmt;
    fmt.setFontWeight(w);
    mergeCurrentCharFormat(fmt);
}

void QTextEdit::setFontUnderline(bool underline)
{
    QTextCharFormat fmt;
    fmt.setFontUnderline(underline);
    mergeCurrentCharFormat(fmt);
}

void QTextEdit::setFontItalic(bool italic)
{
    QTextCharFormat fmt;
    fmt.setFontItalic(italic);
    mergeCurrentCharFormat(fmt);
}

void QTextEdit::setTextColor(const QColor &c)
{
    QTextCharFormat fmt;
    fmt.setForeground(QBrush(c));
    mergeCurrentCharFormat(fmt);
}

void QTextEdit::setCurrentFont(const QFont &f)
{
    QTextCharFormat fmt;
    fmt.setFont(f);
    mergeCurrentCharFormat(fmt);
}

void QTextEdit::undo()
{
    Q_D(QTextEdit);
    d->control->undo();
}

void QTextEdit::redo()
{
    Q_D(QTextEdit);
    d->control->redo();
}

#ifndef QT_NO_CLIPBOARD

void QTextEdit::cut()
{
    Q_D(QTextEdit);
    d->control->cut();
}

void QTextEdit::copy()
{
    Q_D(QTextEdit);
    d->control->copy();
}

void QTextEdit::paste()
{
    Q_D(QTextEdit);
    d->control->paste();
}
#endif

void QTextEdit::clear()
{
    Q_D(QTextEdit);
    // clears and sets empty content
    d->control->clear();
}


void QTextEdit::selectAll()
{
    Q_D(QTextEdit);
    d->control->selectAll();
}

bool QTextEdit::event(QEvent *e)
{
    Q_D(QTextEdit);
    if (e->type() == QEvent::ContextMenu
        && static_cast<QContextMenuEvent *>(e)->reason() == QContextMenuEvent::Keyboard) {
        Q_D(QTextEdit);
        ensureCursorVisible();
        const QPoint cursorPos = cursorRect().center();
        QContextMenuEvent ce(QContextMenuEvent::Keyboard, cursorPos, d->viewport->mapToGlobal(cursorPos));
        ce.setAccepted(e->isAccepted());
        const bool result = QAbstractScrollArea::event(&ce);
        e->setAccepted(ce.isAccepted());
        return result;
    } else if (e->type() == QEvent::ShortcutOverride) {
        d->sendControlEvent(e);
    }
    return QAbstractScrollArea::event(e);
}

void QTextEdit::timerEvent(QTimerEvent *e)
{
    Q_D(QTextEdit);
    if (e->timerId() == d->autoScrollTimer.timerId()) {
        const QPoint globalPos = QCursor::pos();
        const QPoint pos = d->viewport->mapFromGlobal(globalPos);
        QMouseEvent ev(QEvent::MouseMove, pos, globalPos, Qt::LeftButton, Qt::LeftButton, Qt::NoModifier);
        mouseMoveEvent(&ev);
    }
#ifdef QT_KEYPAD_NAVIGATION
    else if (e->timerId() == d->deleteAllTimer.timerId()) {
        d->deleteAllTimer.stop();
        clear();
    }
#endif
}

void QTextEdit::setPlainText(const QString &text)
{
    Q_D(QTextEdit);
    d->control->setPlainText(text);
    d->preferRichText = false;
}

void QTextEdit::setHtml(const QString &text)
{
    Q_D(QTextEdit);
    d->control->setHtml(text);
    d->preferRichText = true;
}

void QTextEdit::keyPressEvent(QKeyEvent *e)
{
    Q_D(QTextEdit);

#ifdef QT_KEYPAD_NAVIGATION
    switch (e->key()) {
        case Qt::Key_Select:
            if (QApplication::keypadNavigationEnabled())
                setEditFocus(!hasEditFocus());
            break;
        case Qt::Key_Back:
        case Qt::Key_No:
            if (!QApplication::keypadNavigationEnabled()
                    || (QApplication::keypadNavigationEnabled() && !hasEditFocus())) {
                e->ignore();
                return;
            }
            break;
        default:
            if (QApplication::keypadNavigationEnabled()) {
                if (!hasEditFocus() && !(e->modifiers() & Qt::ControlModifier)) {
                    if (e->text()[0].isPrint()) {
                        setEditFocus(true);
                        clear();
                    } else {
                        e->ignore();
                        return;
                    }
                }
            }
            break;
    }
#endif

    if (!(d->control->textInteractionFlags() & Qt::TextEditable)) {
        switch (e->key()) {
            case Qt::Key_Space:
                e->accept();
                if (e->modifiers() & Qt::ShiftModifier)
                    d->vbar->triggerAction(QAbstractSlider::SliderPageStepSub);
                else
                    d->vbar->triggerAction(QAbstractSlider::SliderPageStepAdd);
                break;
            default:
                d->sendControlEvent(e);
                if (!e->isAccepted() && e->modifiers() == Qt::NoModifier) {
                    if (e->key() == Qt::Key_Home) {
                        d->vbar->triggerAction(QAbstractSlider::SliderToMinimum);
                        e->accept();
                    } else if (e->key() == Qt::Key_End) {
                        d->vbar->triggerAction(QAbstractSlider::SliderToMaximum);
                        e->accept();
                    }
                }
                if (!e->isAccepted()) {
                    QAbstractScrollArea::keyPressEvent(e);
                }
        }
        return;
    }

#ifndef QT_NO_SHORTCUT
    if (e == QKeySequence::MoveToPreviousPage) {
            e->accept();
            d->pageUpDown(QTextCursor::Up, QTextCursor::MoveAnchor);
            return;
    } else if (e == QKeySequence::MoveToNextPage) {
            e->accept();
            d->pageUpDown(QTextCursor::Down, QTextCursor::MoveAnchor);
            return;
    } else if (e == QKeySequence::SelectPreviousPage) {
            e->accept();
            d->pageUpDown(QTextCursor::Up, QTextCursor::KeepAnchor);
            return;
    } else if (e ==QKeySequence::SelectNextPage) {
            e->accept();
            d->pageUpDown(QTextCursor::Down, QTextCursor::KeepAnchor);
            return;
    }
#endif // QT_NO_SHORTCUT

    {
        QTextCursor cursor = d->control->textCursor();
        const QString text = e->text();
        if (cursor.atBlockStart()
            && (d->autoFormatting & AutoBulletList)
            && (text.length() == 1)
            && (text.at(0) == QLatin1Char('-') || text.at(0) == QLatin1Char('*'))
            && (!cursor.currentList())) {

            d->createAutoBulletList();
            e->accept();
            return;
        }
    }

    d->sendControlEvent(e);
#ifdef QT_KEYPAD_NAVIGATION
    if (!e->isAccepted()) {
        switch (e->key()) {
            case Qt::Key_Up:
            case Qt::Key_Down:
                if (QApplication::keypadNavigationEnabled()) {
                    // Cursor position didn't change, so we want to leave
                    // these keys to change focus.
                    e->ignore();
                    return;
                }
                break;
            case Qt::Key_Back:
                if (!e->isAutoRepeat()) {
                    if (QApplication::keypadNavigationEnabled()) {
                        if (document()->isEmpty()) {
                            setEditFocus(false);
                        } else if (!d->deleteAllTimer.isActive()) {
                            e->accept();
                            d->deleteAllTimer.start(750, this);
                        }
                    } else {
                        e->ignore();
                        return;
                    }
                }
                break;
            default: break;
        }
    }
#endif
}

void QTextEdit::keyReleaseEvent(QKeyEvent *e)
{
#ifdef QT_KEYPAD_NAVIGATION
    Q_D(QTextEdit);
    if (QApplication::keypadNavigationEnabled()) {
        if (!e->isAutoRepeat() && e->key() == Qt::Key_Back
            && d->deleteAllTimer.isActive()) {
            d->deleteAllTimer.stop();
            QTextCursor cursor = d->control->textCursor();
            QTextBlockFormat blockFmt = cursor.blockFormat();

            QTextList *list = cursor.currentList();
            if (list && cursor.atBlockStart()) {
                list->remove(cursor.block());
            } else if (cursor.atBlockStart() && blockFmt.indent() > 0) {
                blockFmt.setIndent(blockFmt.indent() - 1);
                cursor.setBlockFormat(blockFmt);
            } else {
                cursor.deletePreviousChar();
            }
            setTextCursor(cursor);
        }
    }
#else
    Q_UNUSED(e);
#endif
}

QVariant QTextEdit::loadResource(int type, const QUrl &name)
{
    Q_UNUSED(type);
    Q_UNUSED(name);
    return QVariant();
}

void QTextEdit::resizeEvent(QResizeEvent *e)
{
    Q_D(QTextEdit);
    if (d->lineWrap == WidgetWidth) {
        if (e->oldSize().width() == e->size().width()
            && e->oldSize().height() != e->size().height())
            d->_q_adjustScrollbars();
        else
            d->relayoutDocument();
    } else {
        d->_q_adjustScrollbars();
    }
}

void QTextEditPrivate::relayoutDocument()
{
    QTextDocument *doc = control->document();
    QAbstractTextDocumentLayout *layout = doc->documentLayout();

    if (QTextDocumentLayout *tlayout = qobject_cast<QTextDocumentLayout *>(layout)) {
        if (lineWrap == QTextEdit::FixedColumnWidth)
            tlayout->setFixedColumnWidth(lineWrapColumnOrWidth);
        else
            tlayout->setFixedColumnWidth(-1);
    }

    QTextDocumentLayout *tlayout = qobject_cast<QTextDocumentLayout *>(layout);
    QSize lastUsedSize;
    if (tlayout)
        lastUsedSize = tlayout->dynamicDocumentSize().toSize();
    else
        lastUsedSize = layout->documentSize().toSize();

    // ignore calls to _q_adjustScrollbars caused by an emission of the
    // usedSizeChanged() signal in the layout, as we're calling it
    // later on our own anyway (or deliberately not) .
    const bool oldIgnoreScrollbarAdjustment = ignoreAutomaticScrollbarAdjustment;
    ignoreAutomaticScrollbarAdjustment = true;

    int width = 0;
    switch (lineWrap) {
        case QTextEdit::NoWrap:
            width = -1;
            break;
        case QTextEdit::WidgetWidth:
            width = viewport->width();
            break;
        case QTextEdit::FixedPixelWidth:
            width = lineWrapColumnOrWidth;
            break;
        case QTextEdit::FixedColumnWidth:
            width = 0;
            break;
    }

    doc->setPageSize(QSize(width, INT_MAX));
    if (tlayout)
        tlayout->ensureLayouted(verticalOffset() + viewport->height());

    ignoreAutomaticScrollbarAdjustment = oldIgnoreScrollbarAdjustment;

    QSize usedSize;
    if (tlayout)
        usedSize = tlayout->dynamicDocumentSize().toSize();
    else
        usedSize = layout->documentSize().toSize();

    // this is an obscure situation in the layout that can happen:
    // if a character at the end of a line is the tallest one and therefore
    // influencing the total height of the line and the line right below it
    // is always taller though, then it can happen that if due to line breaking
    // that tall character wraps into the lower line the document not only shrinks
    // horizontally (causing the character to wrap in the first place) but also
    // vertically, because the original line is now smaller and the one below kept
    // its size. So a layout with less width _can_ take up less vertical space, too.
    // If the wider case causes a vertical scrollbar to appear and the narrower one
    // (narrower because the vertical scrollbar takes up horizontal space)) to disappear
    // again then we have an endless loop, as _q_adjustScrollBars sets new ranges on the
    // scrollbars, the QAbstractScrollArea will find out about it and try to show/hide the scrollbars
    // again. That's why we try to detect this case here and break out.
    //
    // (if you change this please also check the layoutingLoop() testcase in
    // QTextEdit's autotests)
    if (lastUsedSize.isValid()
        && !vbar->isHidden()
        && viewport->width() < lastUsedSize.width()
        && usedSize.height() < lastUsedSize.height()
        && usedSize.height() <= viewport->height())
        return;

    _q_adjustScrollbars();
}

void QTextEditPrivate::paint(QPainter *p, QPaintEvent *e)
{
    const int xOffset = horizontalOffset();
    const int yOffset = verticalOffset();

    QRect r = e->rect();
    p->translate(-xOffset, -yOffset);
    r.translate(xOffset, yOffset);

    control->drawContents(p, r);
}

void QTextEdit::paintEvent(QPaintEvent *e)
{
    Q_D(QTextEdit);
    QPainter p(d->viewport);
    d->paint(&p, e);
}

void QTextEditPrivate::_q_currentCharFormatChanged(const QTextCharFormat &fmt)
{
    Q_Q(QTextEdit);
    emit q->currentCharFormatChanged(fmt);
#ifdef QT3_SUPPORT
    // compat signals
    emit q->currentFontChanged(fmt.font());
    emit q->currentColorChanged(fmt.foreground().color());
#endif
}

void QTextEdit::mousePressEvent(QMouseEvent *e)
{
    Q_D(QTextEdit);
    d->sendControlEvent(e);
}

void QTextEdit::mouseMoveEvent(QMouseEvent *e)
{
    Q_D(QTextEdit);
    const QPoint pos = e->pos();
    d->sendControlEvent(e);
    if (!(e->buttons() & Qt::LeftButton))
        return;
    if (d->autoScrollTimer.isActive()) {
        if (d->viewport->rect().contains(pos))
            d->autoScrollTimer.stop();
    } else {
        if (!d->viewport->rect().contains(pos))
            d->autoScrollTimer.start(100, this);
    }
}

void QTextEdit::mouseReleaseEvent(QMouseEvent *e)
{
    Q_D(QTextEdit);
    d->autoScrollTimer.stop();
    d->sendControlEvent(e);
}

void QTextEdit::mouseDoubleClickEvent(QMouseEvent *e)
{
    Q_D(QTextEdit);
    d->sendControlEvent(e);
}

bool QTextEdit::focusNextPrevChild(bool next)
{
    Q_D(const QTextEdit);
    if (!d->tabChangesFocus && d->control->textInteractionFlags() & Qt::TextEditable)
        return false;
    return QAbstractScrollArea::focusNextPrevChild(next);
}

void QTextEdit::contextMenuEvent(QContextMenuEvent *e)
{
    Q_D(QTextEdit);
    d->sendControlEvent(e);
}

#ifndef QT_NO_DRAGANDDROP

void QTextEdit::dragEnterEvent(QDragEnterEvent *e)
{
    Q_D(QTextEdit);
    d->sendControlEvent(e);
}

void QTextEdit::dragLeaveEvent(QDragLeaveEvent *e)
{
    Q_D(QTextEdit);
    d->sendControlEvent(e);
}

void QTextEdit::dragMoveEvent(QDragMoveEvent *e)
{
    Q_D(QTextEdit);
    d->sendControlEvent(e);
}

void QTextEdit::dropEvent(QDropEvent *e)
{
    Q_D(QTextEdit);
    d->sendControlEvent(e);
}

#endif // QT_NO_DRAGANDDROP

void QTextEdit::inputMethodEvent(QInputMethodEvent *e)
{
    Q_D(QTextEdit);
#ifdef QT_KEYPAD_NAVIGATION
    if (d->control->textInteractionFlags() & Qt::TextEditable
        && QApplication::keypadNavigationEnabled()
        && !hasEditFocus())
        setEditFocus(true);
#endif
    d->sendControlEvent(e);
}

void QTextEdit::scrollContentsBy(int dx, int dy)
{
    Q_D(QTextEdit);
    if (isRightToLeft())
        dx = -dx;
    d->viewport->scroll(dx, dy);
}

QVariant QTextEdit::inputMethodQuery(Qt::InputMethodQuery property) const
{
    Q_D(const QTextEdit);
    QVariant v = d->control->inputMethodQuery(property);
    const QPoint offset(-d->horizontalOffset(), -d->verticalOffset());
    if (v.type() == QVariant::RectF)
        v = v.toRectF().toRect().translated(offset);
    else if (v.type() == QVariant::PointF)
        v = v.toPointF().toPoint() + offset;
    else if (v.type() == QVariant::Rect)
        v = v.toRect().translated(offset);
    else if (v.type() == QVariant::Point)
        v = v.toPoint() + offset;
    return v;
}

void QTextEdit::focusInEvent(QFocusEvent *e)
{
    Q_D(QTextEdit);
    QAbstractScrollArea::focusInEvent(e);
    d->sendControlEvent(e);
}

void QTextEdit::focusOutEvent(QFocusEvent *e)
{
    Q_D(QTextEdit);
    QAbstractScrollArea::focusOutEvent(e);
    d->sendControlEvent(e);
}

void QTextEdit::showEvent(QShowEvent *)
{
    Q_D(QTextEdit);
    if (!d->anchorToScrollToWhenVisible.isEmpty()) {
        scrollToAnchor(d->anchorToScrollToWhenVisible);
        d->anchorToScrollToWhenVisible.clear();
        d->showCursorOnInitialShow = false;
    } else if (d->showCursorOnInitialShow) {
        d->showCursorOnInitialShow = false;
        ensureCursorVisible();
    }
}

void QTextEdit::changeEvent(QEvent *e)
{
    Q_D(QTextEdit);
    QAbstractScrollArea::changeEvent(e);
    if (e->type() == QEvent::ApplicationFontChange
        || e->type() == QEvent::FontChange) {
        d->control->document()->setDefaultFont(font());
    }  else if(e->type() == QEvent::ActivationChange) {
        if (!isActiveWindow())
            d->autoScrollTimer.stop();
    } else if (e->type() == QEvent::EnabledChange) {
        e->setAccepted(isEnabled());
        d->sendControlEvent(e);
    } else if (e->type() == QEvent::PaletteChange) {
        d->control->setPalette(palette());
    }
}

#ifndef QT_NO_WHEELEVENT
void QTextEdit::wheelEvent(QWheelEvent *e)
{
    Q_D(QTextEdit);
    if (!(d->control->textInteractionFlags() & Qt::TextEditable)) {
        if (e->modifiers() & Qt::ControlModifier) {
            const int delta = e->delta();
            if (delta > 0)
                zoomOut();
            else if (delta < 0)
                zoomIn();
            return;
        }
    }
    QAbstractScrollArea::wheelEvent(e);
    updateMicroFocus();
}
#endif

#ifndef QT_NO_CONTEXTMENU

QMenu *QTextEdit::createStandardContextMenu()
{
    Q_D(QTextEdit);
    return d->control->createStandardContextMenu(QPointF(), this);
}
#endif // QT_NO_CONTEXTMENU

QTextCursor QTextEdit::cursorForPosition(const QPoint &pos) const
{
    Q_D(const QTextEdit);
    return d->control->cursorForPosition(d->mapToContents(pos));
}

QRect QTextEdit::cursorRect(const QTextCursor &cursor) const
{
    Q_D(const QTextEdit);
    if (cursor.isNull())
        return QRect();

    QRect r = d->control->cursorRect(cursor).toRect();
    r.translate(-d->horizontalOffset(),-d->verticalOffset());
    return r;
}

QRect QTextEdit::cursorRect() const
{
    Q_D(const QTextEdit);
    QRect r = d->control->cursorRect().toRect();
    r.translate(-d->horizontalOffset(),-d->verticalOffset());
    return r;
}


QString QTextEdit::anchorAt(const QPoint& pos) const
{
    Q_D(const QTextEdit);
    return d->control->anchorAt(d->mapToContents(pos));
}

bool QTextEdit::overwriteMode() const
{
    Q_D(const QTextEdit);
    return d->control->overwriteMode();
}

void QTextEdit::setOverwriteMode(bool overwrite)
{
    Q_D(QTextEdit);
    d->control->setOverwriteMode(overwrite);
}

int QTextEdit::tabStopWidth() const
{
    Q_D(const QTextEdit);
    return d->control->tabStopWidth();
}

void QTextEdit::setTabStopWidth(int width)
{
    Q_D(QTextEdit);
    d->control->setTabStopWidth(width);
}

int QTextEdit::cursorWidth() const
{
    Q_D(const QTextEdit);
    return d->control->cursorWidth();
}

void QTextEdit::setCursorWidth(int width)
{
    Q_D(QTextEdit);
    d->control->setCursorWidth(width);
}

bool QTextEdit::acceptRichText() const
{
    Q_D(const QTextEdit);
    return d->control->acceptRichText();
}

void QTextEdit::setAcceptRichText(bool accept)
{
    Q_D(QTextEdit);
    d->control->setAcceptRichText(accept);
}

void QTextEdit::setExtraSelections(const QList<ExtraSelection> &selections)
{
    Q_D(QTextEdit);
    d->control->setExtraSelections(selections);
}

QList<QTextEdit::ExtraSelection> QTextEdit::extraSelections() const
{
    Q_D(const QTextEdit);
    return d->control->extraSelections();
}

QMimeData *QTextEdit::createMimeDataFromSelection() const
{
    Q_D(const QTextEdit);
    return d->control->QTextControl::createMimeDataFromSelection();
}

bool QTextEdit::canInsertFromMimeData(const QMimeData *source) const
{
    Q_D(const QTextEdit);
    return d->control->QTextControl::canInsertFromMimeData(source);
}

void QTextEdit::insertFromMimeData(const QMimeData *source)
{
    Q_D(QTextEdit);
    d->control->QTextControl::insertFromMimeData(source);
}

bool QTextEdit::isReadOnly() const
{
    Q_D(const QTextEdit);
    return !(d->control->textInteractionFlags() & Qt::TextEditable);
}

void QTextEdit::setReadOnly(bool ro)
{
    Q_D(QTextEdit);
    Qt::TextInteractionFlags flags = Qt::NoTextInteraction;
    if (ro) {
        flags = Qt::TextSelectableByMouse;
#ifndef QT_NO_TEXTBROWSER
        if (qobject_cast<QTextBrowser *>(this))
            flags |= Qt::TextBrowserInteraction;
#endif
    } else {
        flags = Qt::TextEditorInteraction;
    }
    d->control->setTextInteractionFlags(flags);
}

void QTextEdit::setTextInteractionFlags(Qt::TextInteractionFlags flags)
{
    Q_D(QTextEdit);
    d->control->setTextInteractionFlags(flags);
}

Qt::TextInteractionFlags QTextEdit::textInteractionFlags() const
{
    Q_D(const QTextEdit);
    return d->control->textInteractionFlags();
}

void QTextEdit::mergeCurrentCharFormat(const QTextCharFormat &modifier)
{
    Q_D(QTextEdit);
    d->control->mergeCurrentCharFormat(modifier);
}

void QTextEdit::setCurrentCharFormat(const QTextCharFormat &format)
{
    Q_D(QTextEdit);
    d->control->setCurrentCharFormat(format);
}

QTextCharFormat QTextEdit::currentCharFormat() const
{
    Q_D(const QTextEdit);
    return d->control->currentCharFormat();
}

QTextEdit::AutoFormatting QTextEdit::autoFormatting() const
{
    Q_D(const QTextEdit);
    return d->autoFormatting;
}

void QTextEdit::setAutoFormatting(AutoFormatting features)
{
    Q_D(QTextEdit);
    d->autoFormatting = features;
}

void QTextEdit::insertPlainText(const QString &text)
{
    Q_D(QTextEdit);
    d->control->insertPlainText(text);
}

void QTextEdit::insertHtml(const QString &text)
{
    Q_D(QTextEdit);
    d->control->insertHtml(text);
}

void QTextEdit::scrollToAnchor(const QString &name)
{
    Q_D(QTextEdit);
    if (name.isEmpty())
        return;

    if (!isVisible()) {
        d->anchorToScrollToWhenVisible = name;
        return;
    }

    QPointF p = d->control->anchorPosition(name);
    d->vbar->setValue(qRound(p.y()));
}

void QTextEdit::zoomIn(int range)
{
    QFont f = font();
    const int newSize = f.pointSize() + range;
    if (newSize <= 0)
        return;
    f.setPointSize(newSize);
    setFont(f);
}

void QTextEdit::zoomOut(int range)
{
    zoomIn(-range);
}

void QTextEdit::moveCursor(QTextCursor::MoveOperation operation, QTextCursor::MoveMode mode)
{
    Q_D(QTextEdit);
    d->control->moveCursor(operation, mode);
}

bool QTextEdit::canPaste() const
{
    Q_D(const QTextEdit);
    return d->control->canPaste();
}

bool QTextEdit::tabChangesFocus() const
{
    Q_D(const QTextEdit);
    return d->tabChangesFocus;
}

void QTextEdit::setTabChangesFocus(bool b)
{
    Q_D(QTextEdit);
    d->tabChangesFocus = b;
}

QTextEdit::LineWrapMode QTextEdit::lineWrapMode() const
{
    Q_D(const QTextEdit);
    return d->lineWrap;
}

void QTextEdit::setLineWrapMode(LineWrapMode wrap)
{
    Q_D(QTextEdit);
    if (d->lineWrap == wrap)
        return;
    d->lineWrap = wrap;
    d->relayoutDocument();
}

int QTextEdit::lineWrapColumnOrWidth() const
{
    Q_D(const QTextEdit);
    return d->lineWrapColumnOrWidth;
}

void QTextEdit::setLineWrapColumnOrWidth(int w)
{
    Q_D(QTextEdit);
    d->lineWrapColumnOrWidth = w;
    d->relayoutDocument();
}

QTextOption::WrapMode QTextEdit::wordWrapMode() const
{
    Q_D(const QTextEdit);
    return d->control->wordWrapMode();
}

void QTextEdit::setWordWrapMode(QTextOption::WrapMode mode)
{
    Q_D(QTextEdit);
    d->control->setWordWrapMode(mode);
}

bool QTextEdit::find(const QString &exp, QTextDocument::FindFlags options)
{
    Q_D(QTextEdit);
    return d->control->find(exp, options);
}

void QTextEdit::setText(const QString &text)
{
    Q_D(QTextEdit);
    if (d->textFormat == Qt::AutoText)
        d->textFormat = Qt::mightBeRichText(text) ? Qt::RichText : Qt::PlainText;
    if (d->textFormat == Qt::RichText || d->textFormat == Qt::LogText)
        setHtml(text);
    else
        setPlainText(text);
}

#ifdef QT3_SUPPORT

void QTextEdit::moveCursor(CursorAction action, QTextCursor::MoveMode mode)
{
    Q_D(QTextEdit);
    if (action == MovePageUp) {
        d->pageUpDown(QTextCursor::Up, mode);
        return;
    } else if (action == MovePageDown) {
        d->pageUpDown(QTextCursor::Down, mode);
        return;
    }

    QTextCursor cursor = d->control->textCursor();
    QTextCursor::MoveOperation op = QTextCursor::NoMove;
    switch (action) {
        case MoveBackward: op = QTextCursor::Left; break;
        case MoveForward: op = QTextCursor::Right; break;
        case MoveWordBackward: op = QTextCursor::WordLeft; break;
        case MoveWordForward: op = QTextCursor::WordRight; break;
        case MoveUp: op = QTextCursor::Up; break;
        case MoveDown: op = QTextCursor::Down; break;
        case MoveLineStart: op = QTextCursor::StartOfLine; break;
        case MoveLineEnd: op = QTextCursor::EndOfLine; break;
        case MoveHome: op = QTextCursor::Start; break;
        case MoveEnd: op = QTextCursor::End; break;
        default: return;
    }
    cursor.movePosition(op, mode);
    d->control->setTextCursor(cursor);
}

void QTextEdit::moveCursor(CursorAction action, bool select)
{
    moveCursor(action, select ? QTextCursor::KeepAnchor : QTextCursor::MoveAnchor);
}

void QTextEdit::doKeyboardAction(KeyboardAction action)
{
    Q_D(QTextEdit);
    QTextCursor cursor = d->control->textCursor();
    switch (action) {
        case ActionBackspace: cursor.deletePreviousChar(); break;
        case ActionDelete: cursor.deleteChar(); break;
        case ActionReturn: cursor.insertBlock(); break;
        case ActionKill: {
                QTextBlock block = cursor.block();
                if (cursor.position() == block.position() + block.length() - 2)
                    cursor.movePosition(QTextCursor::Right, QTextCursor::KeepAnchor);
                else
                    cursor.movePosition(QTextCursor::EndOfBlock, QTextCursor::KeepAnchor);
                cursor.deleteChar();
                break;
            }
        case ActionWordBackspace:
            cursor.movePosition(QTextCursor::PreviousWord, QTextCursor::KeepAnchor);
            cursor.deletePreviousChar();
            break;
        case ActionWordDelete:
            cursor.movePosition(QTextCursor::EndOfWord, QTextCursor::KeepAnchor);
            cursor.deleteChar();
            break;
    }
    d->control->setTextCursor(cursor);
}

QString QTextEdit::text() const
{
    Q_D(const QTextEdit);
    if (d->textFormat == Qt::RichText || d->textFormat == Qt::LogText || (d->textFormat == Qt::AutoText && d->preferRichText))
        return d->control->toHtml();
    else
        return d->control->toPlainText();
}


void QTextEdit::setTextFormat(Qt::TextFormat f)
{
    Q_D(QTextEdit);
    d->textFormat = f;
}

Qt::TextFormat QTextEdit::textFormat() const
{
    Q_D(const QTextEdit);
    return d->textFormat;
}

#endif // QT3_SUPPORT


void QTextEdit::append(const QString &text)
{
    Q_D(QTextEdit);
    const bool atBottom = d->verticalOffset() >= d->vbar->maximum();
    d->control->append(text);
    if (atBottom)
        d->vbar->setValue(d->vbar->maximum());
}

void QTextEdit::ensureCursorVisible()
{
    Q_D(QTextEdit);
    d->control->ensureCursorVisible();
}


#endif // QT_NO_TEXTEDIT

#ifndef QT_NO_CONTEXTMENU
#define NUM_CONTROL_CHARACTERS 10
const struct QUnicodeControlCharacter {
    const char *text;
    ushort character;
} qt_controlCharacters[NUM_CONTROL_CHARACTERS] = {
    { QT_TRANSLATE_NOOP("QUnicodeControlCharacterMenu", "LRM Left-to-right mark"), 0x200e },
    { QT_TRANSLATE_NOOP("QUnicodeControlCharacterMenu", "RLM Right-to-left mark"), 0x200f },
    { QT_TRANSLATE_NOOP("QUnicodeControlCharacterMenu", "ZWJ Zero width joiner"), 0x200d },
    { QT_TRANSLATE_NOOP("QUnicodeControlCharacterMenu", "ZWNJ Zero width non-joiner"), 0x200c },
    { QT_TRANSLATE_NOOP("QUnicodeControlCharacterMenu", "ZWSP Zero width space"), 0x200b },
    { QT_TRANSLATE_NOOP("QUnicodeControlCharacterMenu", "LRE Start of left-to-right embedding"), 0x202a },
    { QT_TRANSLATE_NOOP("QUnicodeControlCharacterMenu", "RLE Start of right-to-left embedding"), 0x202b },
    { QT_TRANSLATE_NOOP("QUnicodeControlCharacterMenu", "LRO Start of left-to-right override"), 0x202d },
    { QT_TRANSLATE_NOOP("QUnicodeControlCharacterMenu", "RLO Start of right-to-left override"), 0x202e },
    { QT_TRANSLATE_NOOP("QUnicodeControlCharacterMenu", "PDF Pop directional formatting"), 0x202c },
};

QUnicodeControlCharacterMenu::QUnicodeControlCharacterMenu(QObject *_editWidget, QWidget *parent)
    : QMenu(parent), editWidget(_editWidget)
{
    setTitle(tr("Insert Unicode control character"));
    for (int i = 0; i < NUM_CONTROL_CHARACTERS; ++i) {
        addAction(tr(qt_controlCharacters[i].text), this, SLOT(menuActionTriggered()));
    }
}

void QUnicodeControlCharacterMenu::menuActionTriggered()
{
    QAction *a = qobject_cast<QAction *>(sender());
    int idx = actions().indexOf(a);
    if (idx < 0 || idx >= NUM_CONTROL_CHARACTERS)
        return;
    QChar c(qt_controlCharacters[idx].character);
    QString str(c);

#ifndef QT_NO_TEXTEDIT
    if (QTextEdit *edit = qobject_cast<QTextEdit *>(editWidget)) {
        edit->insertPlainText(str);
        return;
    }
#endif
    if (QTextControl *control = qobject_cast<QTextControl *>(editWidget)) {
        control->insertPlainText(str);
    }
#ifndef QT_NO_LINEEDIT
    if (QLineEdit *edit = qobject_cast<QLineEdit *>(editWidget)) {
        edit->insert(str);
        return;
    }
#endif
}
#endif // QT_NO_CONTEXTMENU

#include "moc_qtextedit.cpp"
#include "moc_qtextedit_p.cpp"

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