FCL/sf/mw/qt: comparison util/src/gui/widgets/qplaintextedit.cpp

equal deleted inserted replaced

-:41300fa6a67c
+:f7bc934e204c
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtGui module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+#include "qplaintextedit_p.h"
+#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 "private/qabstracttextdocumentlayout_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>
+#ifndef QT_NO_TEXTEDIT
+QT_BEGIN_NAMESPACE
+static inline bool shouldEnableInputMethod(QPlainTextEdit *plaintextedit)
+{
+return !plaintextedit->isReadOnly();
+}
+class QPlainTextDocumentLayoutPrivate : public QAbstractTextDocumentLayoutPrivate
+{
+Q_DECLARE_PUBLIC(QPlainTextDocumentLayout)
+public:
+QPlainTextDocumentLayoutPrivate() {
+mainViewPrivate = 0;
+width = 0;
+maximumWidth = 0;
+maximumWidthBlockNumber = 0;
+blockCount = 1;
+blockUpdate = blockDocumentSizeChanged = false;
+cursorWidth = 1;
+textLayoutFlags = 0;
+}
+qreal width;
+qreal maximumWidth;
+int maximumWidthBlockNumber;
+int blockCount;
+QPlainTextEditPrivate *mainViewPrivate;
+bool blockUpdate;
+bool blockDocumentSizeChanged;
+int cursorWidth;
+int textLayoutFlags;
+void layoutBlock(const QTextBlock &block);
+qreal blockWidth(const QTextBlock &block);
+void relayout();
+};
+/*! \class QPlainTextDocumentLayout
+\since 4.4
+\brief The QPlainTextDocumentLayout class implements a plain text layout for QTextDocument
+\ingroup richtext-processing
+A QPlainTextDocumentLayout is required for text documents that can
+be display or edited in a QPlainTextEdit. See
+QTextDocument::setDocumentLayout().
+QPlainTextDocumentLayout uses the QAbstractTextDocumentLayout API
+that QTextDocument requires, but redefines it partially in order to
+support plain text better. For instances, it does not operate on
+vertical pixels, but on paragraphs (called blocks) instead. The
+height of a document is identical to the number of paragraphs it
+contains. The layout also doesn't support tables or nested frames,
+or any sort of advanced text layout that goes beyond a list of
+paragraphs with syntax highlighting.
+*/
+/*!
+Constructs a plain text document layout for the text \a document.
+*/
+QPlainTextDocumentLayout::QPlainTextDocumentLayout(QTextDocument *document)
+:QAbstractTextDocumentLayout(* new QPlainTextDocumentLayoutPrivate, document) {
+}
+/*!
+Destructs a plain text document layout.
+*/
+QPlainTextDocumentLayout::~QPlainTextDocumentLayout() {}
+/*!
+\reimp
+*/
+void QPlainTextDocumentLayout::draw(QPainter *, const PaintContext &)
+{
+}
+/*!
+\reimp
+*/
+int QPlainTextDocumentLayout::hitTest(const QPointF &, Qt::HitTestAccuracy ) const
+{
+//     this function is used from
+//     QAbstractTextDocumentLayout::anchorAt(), but is not
+//     implementable in a plain text document layout, because the
+//     layout depends on the top block and top line which depends on
+//     the view
+return -1;
+}
+/*!
+\reimp
+*/
+int QPlainTextDocumentLayout::pageCount() const
+{ return 1; }
+/*!
+\reimp
+*/
+QSizeF QPlainTextDocumentLayout::documentSize() const
+{
+Q_D(const QPlainTextDocumentLayout);
+return QSizeF(d->maximumWidth, document()->lineCount());
+}
+/*!
+\reimp
+*/
+QRectF QPlainTextDocumentLayout::frameBoundingRect(QTextFrame *) const
+{
+Q_D(const QPlainTextDocumentLayout);
+return QRectF(0, 0, qMax(d->width, d->maximumWidth), qreal(INT_MAX));
+}
+/*!
+\reimp
+*/
+QRectF QPlainTextDocumentLayout::blockBoundingRect(const QTextBlock &block) const
+{
+if (!block.isValid()) { return QRectF(); }
+QTextLayout *tl = block.layout();
+if (!tl->lineCount())
+const_cast<QPlainTextDocumentLayout*>(this)->layoutBlock(block);
+QRectF br;
+if (block.isVisible()) {
+br = QRectF(QPointF(0, 0), tl->boundingRect().bottomRight());
+if (tl->lineCount() == 1)
+br.setWidth(qMax(br.width(), tl->lineAt(0).naturalTextWidth()));
+qreal margin = document()->documentMargin();
+br.adjust(0, 0, margin, 0);
+if (!block.next().isValid())
+br.adjust(0, 0, 0, margin);
+}
+return br;
+}
+/*!
+Ensures that \a block has a valid layout
+*/
+void QPlainTextDocumentLayout::ensureBlockLayout(const QTextBlock &block) const
+{
+if (!block.isValid())
+return;
+QTextLayout *tl = block.layout();
+if (!tl->lineCount())
+const_cast<QPlainTextDocumentLayout*>(this)->layoutBlock(block);
+}
+/*! \property QPlainTextDocumentLayout::cursorWidth
+This property specifies the width of the cursor in pixels. The default value is 1.
+*/
+void QPlainTextDocumentLayout::setCursorWidth(int width)
+{
+Q_D(QPlainTextDocumentLayout);
+d->cursorWidth = width;
+}
+int QPlainTextDocumentLayout::cursorWidth() const
+{
+Q_D(const QPlainTextDocumentLayout);
+return d->cursorWidth;
+}
+QPlainTextDocumentLayoutPrivate *QPlainTextDocumentLayout::priv() const
+{
+Q_D(const QPlainTextDocumentLayout);
+return const_cast<QPlainTextDocumentLayoutPrivate*>(d);
+}
+/*!
+Requests a complete update on all views.
+*/
+void QPlainTextDocumentLayout::requestUpdate()
+{
+emit update(QRectF(0., -document()->documentMargin(), 1000000000., 1000000000.));
+}
+void QPlainTextDocumentLayout::setTextWidth(qreal newWidth)
+{
+Q_D(QPlainTextDocumentLayout);
+d->width = d->maximumWidth = newWidth;
+d->relayout();
+}
+qreal QPlainTextDocumentLayout::textWidth() const
+{
+Q_D(const QPlainTextDocumentLayout);
+return d->width;
+}
+void QPlainTextDocumentLayoutPrivate::relayout()
+{
+Q_Q(QPlainTextDocumentLayout);
+QTextBlock block = q->document()->firstBlock();
+while (block.isValid()) {
+block.layout()->clearLayout();
+block.setLineCount(block.isVisible() ? 1 : 0);
+block = block.next();
+}
+emit q->update();
+}
+/*! \reimp
+*/
+void QPlainTextDocumentLayout::documentChanged(int from, int /*charsRemoved*/, int charsAdded)
+{
+Q_D(QPlainTextDocumentLayout);
+QTextDocument *doc = document();
+int newBlockCount = doc->blockCount();
+QTextBlock changeStartBlock = doc->findBlock(from);
+QTextBlock changeEndBlock = doc->findBlock(qMax(0, from + charsAdded - 1));
+if (changeStartBlock == changeEndBlock && newBlockCount == d->blockCount) {
+QTextBlock block = changeStartBlock;
+int blockLineCount = block.layout()->lineCount();
+if (block.isValid() && blockLineCount) {
+QRectF oldBr = blockBoundingRect(block);
+layoutBlock(block);
+QRectF newBr = blockBoundingRect(block);
+if (newBr.height() == oldBr.height()) {
+if (!d->blockUpdate)
+emit updateBlock(block);
+return;
+}
+}
+} else {
+QTextBlock block = changeStartBlock;
+do {
+block.clearLayout();
+if (block == changeEndBlock)
+break;
+block = block.next();
+} while(block.isValid());
+}
+if (newBlockCount != d->blockCount) {
+int changeEnd = changeEndBlock.blockNumber();
+int blockDiff = newBlockCount - d->blockCount;
+int oldChangeEnd = changeEnd - blockDiff;
+if (d->maximumWidthBlockNumber > oldChangeEnd)
+d->maximumWidthBlockNumber += blockDiff;
+d->blockCount = newBlockCount;
+if (d->blockCount == 1)
+d->maximumWidth = blockWidth(doc->firstBlock());
+if (!d->blockDocumentSizeChanged)
+emit documentSizeChanged(documentSize());
+if (blockDiff == 1 && changeEnd == newBlockCount -1 ) {
+if (!d->blockUpdate) {
+QTextBlock b = changeStartBlock;
+for(;;) {
+emit updateBlock(b);
+if (b == changeEndBlock)
+break;
+b = b.next();
+}
+}
+return;
+}
+}
+if (!d->blockUpdate)
+	emit update(QRectF(0., -doc->documentMargin(), 1000000000., 1000000000.)); // optimization potential
+}
+void QPlainTextDocumentLayout::layoutBlock(const QTextBlock &block)
+{
+Q_D(QPlainTextDocumentLayout);
+QTextDocument *doc = document();
+qreal margin = doc->documentMargin();
+qreal blockMaximumWidth = 0;
+qreal height = 0;
+QTextLayout *tl = block.layout();
+QTextOption option = doc->defaultTextOption();
+tl->setTextOption(option);
+int extraMargin = 0;
+if (option.flags() & QTextOption::AddSpaceForLineAndParagraphSeparators) {
+QFontMetrics fm(block.charFormat().font());
+extraMargin += fm.width(QChar(0x21B5));
+}
+tl->beginLayout();
+qreal availableWidth = d->width;
+if (availableWidth <= 0) {
+availableWidth = qreal(INT_MAX); // similar to text edit with pageSize.width == 0
+}
+availableWidth -= 2*margin + extraMargin;
+while (1) {
+QTextLine line = tl->createLine();
+if (!line.isValid())
+break;
+line.setLeadingIncluded(true);
+line.setLineWidth(availableWidth);
+line.setPosition(QPointF(margin, height));
+height += line.height();
+blockMaximumWidth = qMax(blockMaximumWidth, line.naturalTextWidth() + 2*margin);
+}
+tl->endLayout();
+int previousLineCount = doc->lineCount();
+const_cast<QTextBlock&>(block).setLineCount(block.isVisible() ? tl->lineCount() : 0);
+int lineCount = doc->lineCount();
+bool emitDocumentSizeChanged = previousLineCount != lineCount;
+if (blockMaximumWidth > d->maximumWidth) {
+// new longest line
+d->maximumWidth = blockMaximumWidth;
+d->maximumWidthBlockNumber = block.blockNumber();
+emitDocumentSizeChanged = true;
+} else if (block.blockNumber() == d->maximumWidthBlockNumber && blockMaximumWidth < d->maximumWidth) {
+// longest line shrinking
+QTextBlock b = doc->firstBlock();
+d->maximumWidth = 0;
+QTextBlock maximumBlock;
+while (b.isValid()) {
+qreal blockMaximumWidth = blockWidth(b);
+if (blockMaximumWidth > d->maximumWidth) {
+d->maximumWidth = blockMaximumWidth;
+maximumBlock = b;
+}
+b = b.next();
+}
+if (maximumBlock.isValid()) {
+d->maximumWidthBlockNumber = maximumBlock.blockNumber();
+emitDocumentSizeChanged = true;
+}
+}
+if (emitDocumentSizeChanged && !d->blockDocumentSizeChanged)
+emit documentSizeChanged(documentSize());
+}
+qreal QPlainTextDocumentLayout::blockWidth(const QTextBlock &block)
+{
+QTextLayout *layout = block.layout();
+if (!layout->lineCount())
+return 0; // only for layouted blocks
+qreal blockWidth = 0;
+for (int i = 0; i < layout->lineCount(); ++i) {
+QTextLine line = layout->lineAt(i);
+blockWidth = qMax(line.naturalTextWidth() + 8, blockWidth);
+}
+return blockWidth;
+}
+QPlainTextEditControl::QPlainTextEditControl(QPlainTextEdit *parent)
+: QTextControl(parent), textEdit(parent),
+topBlock(0)
+{
+setAcceptRichText(false);
+}
+void QPlainTextEditPrivate::_q_cursorPositionChanged()
+{
+pageUpDownLastCursorYIsValid = false;
+}
+void QPlainTextEditPrivate::_q_verticalScrollbarActionTriggered(int action) {
+if (action == QAbstractSlider::SliderPageStepAdd) {
+pageUpDown(QTextCursor::Down, QTextCursor::MoveAnchor, false);
+} else if (action == QAbstractSlider::SliderPageStepSub) {
+pageUpDown(QTextCursor::Up, QTextCursor::MoveAnchor, false);
+}
+}
+QMimeData *QPlainTextEditControl::createMimeDataFromSelection() const {
+QPlainTextEdit *ed = qobject_cast<QPlainTextEdit *>(parent());
+if (!ed)
+return QTextControl::createMimeDataFromSelection();
+return ed->createMimeDataFromSelection();
+}
+bool QPlainTextEditControl::canInsertFromMimeData(const QMimeData *source) const {
+QPlainTextEdit *ed = qobject_cast<QPlainTextEdit *>(parent());
+if (!ed)
+return QTextControl::canInsertFromMimeData(source);
+return ed->canInsertFromMimeData(source);
+}
+void QPlainTextEditControl::insertFromMimeData(const QMimeData *source) {
+QPlainTextEdit *ed = qobject_cast<QPlainTextEdit *>(parent());
+if (!ed)
+QTextControl::insertFromMimeData(source);
+else
+ed->insertFromMimeData(source);
+}
+int QPlainTextEditPrivate::verticalOffset(int topBlock, int topLine) const
+{
+qreal offset = 0;
+QTextDocument *doc = control->document();
+if (topLine) {
+QTextBlock currentBlock = doc->findBlockByNumber(topBlock);
+QPlainTextDocumentLayout *documentLayout = qobject_cast<QPlainTextDocumentLayout*>(doc->documentLayout());
+Q_ASSERT(documentLayout);
+QRectF r = documentLayout->blockBoundingRect(currentBlock);
+QTextLayout *layout = currentBlock.layout();
+if (layout && topLine <= layout->lineCount()) {
+QTextLine line = layout->lineAt(topLine - 1);
+const QRectF lr = line.naturalTextRect();
+offset = lr.bottom();
+}
+}
+if (topBlock == 0 && topLine == 0)
+offset -= doc->documentMargin(); // top margin
+return (int)offset;
+}
+int QPlainTextEditPrivate::verticalOffset() const {
+return verticalOffset(control->topBlock, topLine);
+}
+QTextBlock QPlainTextEditControl::firstVisibleBlock() const
+{
+return document()->findBlockByNumber(topBlock);
+}
+int QPlainTextEditControl::hitTest(const QPointF &point, Qt::HitTestAccuracy ) const {
+int currentBlockNumber = topBlock;
+QTextBlock currentBlock = document()->findBlockByNumber(currentBlockNumber);
+if (!currentBlock.isValid())
+return -1;
+QPlainTextDocumentLayout *documentLayout = qobject_cast<QPlainTextDocumentLayout*>(document()->documentLayout());
+Q_ASSERT(documentLayout);
+QPointF offset;
+QRectF r = documentLayout->blockBoundingRect(currentBlock);
+while (currentBlock.next().isValid() && r.bottom() + offset.y() <= point.y()) {
+offset.ry() += r.height();
+currentBlock = currentBlock.next();
+++currentBlockNumber;
+r = documentLayout->blockBoundingRect(currentBlock);
+}
+while (currentBlock.previous().isValid() && r.top() + offset.y() > point.y()) {
+offset.ry() -= r.height();
+currentBlock = currentBlock.previous();
+--currentBlockNumber;
+r = documentLayout->blockBoundingRect(currentBlock);
+}
+if (!currentBlock.isValid())
+return -1;
+QTextLayout *layout = currentBlock.layout();
+int off = 0;
+QPointF pos = point - offset;
+for (int i = 0; i < layout->lineCount(); ++i) {
+QTextLine line = layout->lineAt(i);
+const QRectF lr = line.naturalTextRect();
+if (lr.top() > pos.y()) {
+off = qMin(off, line.textStart());
+} else if (lr.bottom() <= pos.y()) {
+off = qMax(off, line.textStart() + line.textLength());
+} else {
+off = line.xToCursor(pos.x(), overwriteMode() ?
+QTextLine::CursorOnCharacter : QTextLine::CursorBetweenCharacters);
+break;
+}
+}
+return currentBlock.position() + off;
+}
+QRectF QPlainTextEditControl::blockBoundingRect(const QTextBlock &block) const {
+int currentBlockNumber = topBlock;
+int blockNumber = block.blockNumber();
+QTextBlock currentBlock = document()->findBlockByNumber(currentBlockNumber);
+if (!currentBlock.isValid())
+return QRectF();
+Q_ASSERT(currentBlock.blockNumber() == currentBlockNumber);
+QTextDocument *doc = document();
+QPlainTextDocumentLayout *documentLayout = qobject_cast<QPlainTextDocumentLayout*>(doc->documentLayout());
+Q_ASSERT(documentLayout);
+QPointF offset;
+if (!block.isValid())
+return QRectF();
+QRectF r = documentLayout->blockBoundingRect(currentBlock);
+int maxVerticalOffset = r.height();
+while (currentBlockNumber < blockNumber && offset.y() - maxVerticalOffset <= 2* textEdit->viewport()->height()) {
+offset.ry() += r.height();
+currentBlock = currentBlock.next();
+++currentBlockNumber;
+if (!currentBlock.isVisible()) {
+currentBlock = doc->findBlockByLineNumber(currentBlock.firstLineNumber());
+currentBlockNumber = currentBlock.blockNumber();
+}
+r = documentLayout->blockBoundingRect(currentBlock);
+}
+while (currentBlockNumber > blockNumber && offset.y() + maxVerticalOffset >= -textEdit->viewport()->height()) {
+currentBlock = currentBlock.previous();
+--currentBlockNumber;
+while (!currentBlock.isVisible()) {
+currentBlock = currentBlock.previous();
+--currentBlockNumber;
+}
+if (!currentBlock.isValid())
+break;
+r = documentLayout->blockBoundingRect(currentBlock);
+offset.ry() -= r.height();
+}
+if (currentBlockNumber != blockNumber) {
+// fallback for blocks out of reach. Give it some geometry at
+// least, and ensure the layout is up to date.
+r = documentLayout->blockBoundingRect(block);
+if (currentBlockNumber > blockNumber)
+offset.ry() -= r.height();
+}
+r.translate(offset);
+return r;
+}
+void QPlainTextEditPrivate::setTopLine(int visualTopLine, int dx)
+{
+QTextDocument *doc = control->document();
+QTextBlock block = doc->findBlockByLineNumber(visualTopLine);
+int blockNumber = block.blockNumber();
+int lineNumber = visualTopLine - block.firstLineNumber();
+setTopBlock(blockNumber, lineNumber, dx);
+}
+void QPlainTextEditPrivate::setTopBlock(int blockNumber, int lineNumber, int dx)
+{
+Q_Q(QPlainTextEdit);
+blockNumber = qMax(0, blockNumber);
+lineNumber = qMax(0, lineNumber);
+QTextDocument *doc = control->document();
+QTextBlock block = doc->findBlockByNumber(blockNumber);
+int newTopLine = block.firstLineNumber() + lineNumber;
+int maxTopLine = vbar->maximum();
+if (newTopLine > maxTopLine) {
+block = doc->findBlockByLineNumber(maxTopLine);
+blockNumber = block.blockNumber();
+lineNumber = maxTopLine - block.firstLineNumber();
+}
+bool vbarSignalsBlocked = vbar->blockSignals(true);
+vbar->setValue(newTopLine);
+vbar->blockSignals(vbarSignalsBlocked);
+if (!dx && blockNumber == control->topBlock && lineNumber == topLine)
+return;
+if (viewport->updatesEnabled() && viewport->isVisible()) {
+int dy = 0;
+if (doc->findBlockByNumber(control->topBlock).isValid()) {
+dy = (int)(-q->blockBoundingGeometry(block).y())
++ verticalOffset() - verticalOffset(blockNumber, lineNumber);
+}
+control->topBlock = blockNumber;
+topLine = lineNumber;
+if (dx || dy)
+viewport->scroll(q->isRightToLeft() ? -dx : dx, dy);
+else
+viewport->update();
+emit q->updateRequest(viewport->rect(), dy);
+} else {
+control->topBlock = blockNumber;
+topLine = lineNumber;
+}
+}
+void QPlainTextEditPrivate::ensureVisible(int position, bool center, bool forceCenter) {
+Q_Q(QPlainTextEdit);
+QRectF visible = QRectF(viewport->rect()).translated(-q->contentOffset());
+QTextBlock block = control->document()->findBlock(position);
+if (!block.isValid())
+return;
+QRectF br = control->blockBoundingRect(block);
+if (!br.isValid())
+return;
+QRectF lr = br;
+QTextLine line = block.layout()->lineForTextPosition(position - block.position());
+Q_ASSERT(line.isValid());
+lr = line.naturalTextRect().translated(br.topLeft());
+if (lr.bottom() >= visible.bottom() || (center && lr.top() < visible.top()) || forceCenter){
+qreal height = visible.height();
+if (center)
+height /= 2;
+qreal h = center ? line.naturalTextRect().center().y() : line.naturalTextRect().bottom();
+QTextBlock previousVisibleBlock = block;
+while (h < height && block.previous().isValid()) {
+previousVisibleBlock = block;
+do {
+block = block.previous();
+} while (!block.isVisible() && block.previous().isValid());
+h += q->blockBoundingRect(block).height();
+}
+int l = 0;
+int lineCount = block.layout()->lineCount();
+int voffset = verticalOffset(block.blockNumber(), 0);
+while (l < lineCount) {
+QRectF lineRect = block.layout()->lineAt(l).naturalTextRect();
+if (h - voffset - lineRect.top() <= height)
+break;
+++l;
+}
+if (l >= lineCount) {
+block = previousVisibleBlock;
+l = 0;
+}
+setTopBlock(block.blockNumber(), l);
+} else if (lr.top() < visible.top()) {
+setTopBlock(block.blockNumber(), line.lineNumber());
+}
+}
+void QPlainTextEditPrivate::updateViewport()
+{
+Q_Q(QPlainTextEdit);
+viewport->update();
+emit q->updateRequest(viewport->rect(), 0);
+}
+QPlainTextEditPrivate::QPlainTextEditPrivate()
+: control(0),
+tabChangesFocus(false),
+lineWrap(QPlainTextEdit::WidgetWidth),
+wordWrap(QTextOption::WrapAtWordBoundaryOrAnywhere),
+clickCausedFocus(0),topLine(0),
+pageUpDownLastCursorYIsValid(false)
+{
+showCursorOnInitialShow = true;
+backgroundVisible = false;
+centerOnScroll = false;
+inDrag = false;
+}
+void QPlainTextEditPrivate::init(const QString &txt)
+{
+Q_Q(QPlainTextEdit);
+control = new QPlainTextEditControl(q);
+QTextDocument *doc = new QTextDocument(control);
+QAbstractTextDocumentLayout *layout = new QPlainTextDocumentLayout(doc);
+doc->setDocumentLayout(layout);
+control->setDocument(doc);
+control->setPalette(q->palette());
+QObject::connect(vbar, SIGNAL(actionTriggered(int)), q, SLOT(_q_verticalScrollbarActionTriggered(int)));
+QObject::connect(control, SIGNAL(microFocusChanged()), q, SLOT(updateMicroFocus()));
+QObject::connect(control, SIGNAL(documentSizeChanged(QSizeF)), q, SLOT(_q_adjustScrollbars()));
+QObject::connect(control, SIGNAL(blockCountChanged(int)), q, SIGNAL(blockCountChanged(int)));
+QObject::connect(control, SIGNAL(updateRequest(QRectF)), q, SLOT(_q_repaintContents(QRectF)));
+QObject::connect(control, SIGNAL(modificationChanged(bool)), q, SIGNAL(modificationChanged(bool)));
+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, SLOT(_q_cursorPositionChanged()));
+QObject::connect(control, SIGNAL(cursorPositionChanged()), q, SIGNAL(cursorPositionChanged()));
+QObject::connect(control, SIGNAL(textChanged()), q, SLOT(updateMicroFocus()));
+// 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->setTextWidth(-1);
+doc->documentLayout()->setPaintDevice(viewport);
+doc->setDefaultFont(q->font());
+if (!txt.isEmpty())
+control->setPlainText(txt);
+hbar->setSingleStep(20);
+vbar->setSingleStep(1);
+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
+originalOffsetY = 0;
+#ifdef Q_WS_WIN
+setSingleFingerPanEnabled(true);
+#endif
+}
+void QPlainTextEditPrivate::_q_repaintContents(const QRectF &contentsRect)
+{
+Q_Q(QPlainTextEdit);
+if (!contentsRect.isValid()) {
+updateViewport();
+return;
+}
+const int xOffset = horizontalOffset();
+const int yOffset = verticalOffset();
+const QRect visibleRect(xOffset, yOffset, viewport->width(), viewport->height());
+QRect r = contentsRect.adjusted(-1, -1, 1, 1).intersected(visibleRect).toAlignedRect();
+if (r.isEmpty())
+return;
+r.translate(-xOffset, -yOffset);
+viewport->update(r);
+emit q->updateRequest(r, 0);
+}
+void QPlainTextEditPrivate::pageUpDown(QTextCursor::MoveOperation op, QTextCursor::MoveMode moveMode, bool moveCursor)
+{
+Q_Q(QPlainTextEdit);
+QTextCursor cursor = control->textCursor();
+if (moveCursor) {
+ensureCursorVisible();
+if (!pageUpDownLastCursorYIsValid)
+pageUpDownLastCursorY = control->cursorRect(cursor).top() - verticalOffset();
+}
+qreal lastY = pageUpDownLastCursorY;
+if (op == QTextCursor::Down) {
+QRectF visible = QRectF(viewport->rect()).translated(-q->contentOffset());
+QTextBlock firstVisibleBlock = q->firstVisibleBlock();
+QTextBlock block = firstVisibleBlock;
+QRectF br = q->blockBoundingRect(block);
+qreal h = 0;
+int atEnd = false;
+while (h + br.height() <= visible.bottom()) {
+if (!block.next().isValid()) {
+atEnd = true;
+lastY = visible.bottom(); // set cursor to last line
+break;
+}
+h += br.height();
+block = block.next();
+br = q->blockBoundingRect(block);
+}
+if (!atEnd) {
+int line = 0;
+qreal diff = visible.bottom() - h;
+int lineCount = block.layout()->lineCount();
+while (line < lineCount - 1) {
+if (block.layout()->lineAt(line).naturalTextRect().bottom() > diff) {
+// the first line that did not completely fit the screen
+break;
+}
+++line;
+}
+setTopBlock(block.blockNumber(), line);
+}
+if (moveCursor) {
+// move using movePosition to keep the cursor's x
+lastY += verticalOffset();
+bool moved = false;
+do {
+moved = cursor.movePosition(op, moveMode);
+} while (moved && control->cursorRect(cursor).top() < lastY);
+}
+} else if (op == QTextCursor::Up) {
+QRectF visible = QRectF(viewport->rect()).translated(-q->contentOffset());
+visible.translate(0, -visible.height()); // previous page
+QTextBlock block = q->firstVisibleBlock();
+qreal h = 0;
+while (h >= visible.top()) {
+if (!block.previous().isValid()) {
+if (control->topBlock == 0 && topLine == 0) {
+lastY = 0; // set cursor to first line
+}
+break;
+}
+block = block.previous();
+QRectF br = q->blockBoundingRect(block);
+h -= br.height();
+}
+int line = 0;
+if (block.isValid()) {
+qreal diff = visible.top() - h;
+int lineCount = block.layout()->lineCount();
+while (line < lineCount) {
+if (block.layout()->lineAt(line).naturalTextRect().top() >= diff)
+break;
+++line;
+}
+if (line == lineCount) {
+if (block.next().isValid() && block.next() != q->firstVisibleBlock()) {
+block = block.next();
+line = 0;
+} else {
+--line;
+}
+}
+}
+setTopBlock(block.blockNumber(), line);
+if (moveCursor) {
+// move using movePosition to keep the cursor's x
+lastY += verticalOffset();
+bool moved = false;
+do {
+moved = cursor.movePosition(op, moveMode);
+} while (moved && control->cursorRect(cursor).top() > lastY);
+}
+}
+if (moveCursor) {
+control->setTextCursor(cursor);
+pageUpDownLastCursorYIsValid = true;
+}
+}
+#ifndef QT_NO_SCROLLBAR
+void QPlainTextEditPrivate::_q_adjustScrollbars()
+{
+Q_Q(QPlainTextEdit);
+QTextDocument *doc = control->document();
+QPlainTextDocumentLayout *documentLayout = qobject_cast<QPlainTextDocumentLayout*>(doc->documentLayout());
+Q_ASSERT(documentLayout);
+bool documentSizeChangedBlocked = documentLayout->priv()->blockDocumentSizeChanged;
+documentLayout->priv()->blockDocumentSizeChanged = true;
+qreal margin = doc->documentMargin();
+int vmax = 0;
+int vSliderLength = 0;
+if (!centerOnScroll && q->isVisible()) {
+QTextBlock block = doc->lastBlock();
+const int visible = static_cast<int>(viewport->rect().height() - margin - 1);
+int y = 0;
+int visibleFromBottom = 0;
+while (block.isValid()) {
+if (!block.isVisible()) {
+block = block.previous();
+continue;
+}
+y += int(documentLayout->blockBoundingRect(block).height());
+QTextLayout *layout = block.layout();
+int layoutLineCount = layout->lineCount();
+if (y > visible) {
+int lineNumber = 0;
+while (lineNumber < layoutLineCount) {
+QTextLine line = layout->lineAt(lineNumber);
+const QRectF lr = line.naturalTextRect();
+if (int(lr.top()) >= y - visible)
+break;
+++lineNumber;
+}
+if (lineNumber < layoutLineCount)
+visibleFromBottom += (layoutLineCount - lineNumber - 1);
+break;
+}
+visibleFromBottom += layoutLineCount;
+block = block.previous();
+}
+vmax = qMax(0, doc->lineCount() - visibleFromBottom);
+vSliderLength = visibleFromBottom;
+} else {
+vmax = qMax(0, doc->lineCount() - 1);
+vSliderLength = viewport->height() / q->fontMetrics().lineSpacing();
+}
+QSizeF documentSize = documentLayout->documentSize();
+vbar->setRange(0, qMax(0, vmax));
+vbar->setPageStep(vSliderLength);
+int visualTopLine = vmax;
+QTextBlock firstVisibleBlock = q->firstVisibleBlock();
+if (firstVisibleBlock.isValid())
+visualTopLine = firstVisibleBlock.firstLineNumber() + topLine;
+bool vbarSignalsBlocked = vbar->blockSignals(true);
+vbar->setValue(visualTopLine);
+vbar->blockSignals(vbarSignalsBlocked);
+hbar->setRange(0, (int)documentSize.width() - viewport->width());
+hbar->setPageStep(viewport->width());
+documentLayout->priv()->blockDocumentSizeChanged = documentSizeChangedBlocked;
+setTopLine(vbar->value());
+}
+#endif
+void QPlainTextEditPrivate::ensureViewportLayouted()
+{
+}
+/*!
+\class QPlainTextEdit
+\since 4.4
+\brief The QPlainTextEdit class provides a widget that is used to edit and display
+plain text.
+\ingroup richtext-processing
+\tableofcontents
+\section1 Introduction and Concepts
+QPlainTextEdit is an advanced viewer/editor supporting plain
+text. It is optimized to handle large documents and to respond
+quickly to user input.
+QPlainText uses very much the same technology and concepts as
+QTextEdit, but is optimized for plain text handling.
+QPlainTextEdit works on paragraphs and characters. A paragraph is
+a formatted string which is word-wrapped to fit into the width of
+the widget. By default when reading plain text, one newline
+signifies a paragraph. A document consists of zero or more
+paragraphs. Paragraphs are separated by hard line breaks. Each
+character within a paragraph has its own attributes, for example,
+font and color.
+The shape of the mouse cursor on a QPlainTextEdit is
+Qt::IBeamCursor by default.  It can be changed through the
+viewport()'s cursor property.
+\section1 Using QPlainTextEdit as a Display Widget
+The text is set or replaced using setPlainText() which deletes the
+existing text and replaces it with the text passed to setPlainText().
+Text can be inserted using the QTextCursor class or using the
+convenience functions insertPlainText(), appendPlainText() or
+paste().
+By default, the text edit wraps words at whitespace to fit within
+the text edit widget. The setLineWrapMode() function is used to
+specify the kind of line wrap you want, \l WidgetWidth or \l
+NoWrap if you don't want any wrapping.  If you use word wrap to
+the widget's width \l WidgetWidth, you can specify whether to
+break on whitespace or anywhere with setWordWrapMode().
+The find() function can be used to find and select a given string
+within the text.
+If you want to limit the total number of paragraphs in a
+QPlainTextEdit, as it is for example useful in a log viewer, then
+you can use the maximumBlockCount property. The combination of
+setMaximumBlockCount() and appendPlainText() turns QPlainTextEdit
+into an efficient viewer for log text. The scrolling can be
+reduced with the centerOnScroll() property, making the log viewer
+even faster. Text can be formatted in a limited way, either using
+a syntax highlighter (see below), or by appending html-formatted
+text with appendHtml(). While QPlainTextEdit does not support
+complex rich text rendering with tables and floats, it does
+support limited paragraph-based formatting that you may need in a
+log viewer.
+\section2 Read-only Key Bindings
+When QPlainTextEdit is used read-only the key bindings are limited to
+navigation, and text may only be selected with the mouse:
+\table
+\header \i Keypresses \i Action
+\row \i Qt::UpArrow        \i Moves one line up.
+\row \i Qt::DownArrow        \i Moves one line down.
+\row \i Qt::LeftArrow        \i Moves one character to the left.
+\row \i Qt::RightArrow        \i Moves one character to the right.
+\row \i PageUp        \i Moves one (viewport) page up.
+\row \i PageDown        \i Moves one (viewport) page down.
+\row \i Home        \i Moves to the beginning of the text.
+\row \i End                \i Moves to the end of the text.
+\row \i Alt+Wheel
+\i Scrolls the page horizontally (the Wheel is the mouse wheel).
+\row \i Ctrl+Wheel        \i Zooms the text.
+\row \i Ctrl+A            \i Selects all text.
+\endtable
+\section1 Using QPlainTextEdit as an Editor
+All the information about using QPlainTextEdit as a display widget also
+applies here.
+Selection of text is handled by the QTextCursor class, which provides
+functionality for creating selections, retrieving the text contents or
+deleting selections. You can retrieve the object that corresponds with
+the user-visible cursor using the textCursor() method. If you want to set
+a selection in QPlainTextEdit just create one on a QTextCursor object and
+then make that cursor the visible cursor using setCursor(). The selection
+can be copied to the clipboard with copy(), or cut to the clipboard with
+cut(). The entire text can be selected using selectAll().
+QPlainTextEdit holds a QTextDocument object which can be retrieved using the
+document() method. You can also set your own document object using setDocument().
+QTextDocument emits a textChanged() signal if the text changes and it also
+provides a isModified() function which will return true if the text has been
+modified since it was either loaded or since the last call to setModified
+with false as argument. In addition it provides methods for undo and redo.
+\section2 Syntax Highlighting
+Just like QTextEdit, QPlainTextEdit works together with
+QSyntaxHighlighter.
+\section2 Editing Key Bindings
+The list of key bindings which are implemented for editing:
+\table
+\header \i Keypresses \i Action
+\row \i Backspace \i Deletes the character to the left of the cursor.
+\row \i Delete \i Deletes the character to the right of the cursor.
+\row \i Ctrl+C \i Copy the selected text to the clipboard.
+\row \i Ctrl+Insert \i Copy the selected text to the clipboard.
+\row \i Ctrl+K \i Deletes to the end of the line.
+\row \i Ctrl+V \i Pastes the clipboard text into text edit.
+\row \i Shift+Insert \i Pastes the clipboard text into text edit.
+\row \i Ctrl+X \i Deletes the selected text and copies it to the clipboard.
+\row \i Shift+Delete \i Deletes the selected text and copies it to the clipboard.
+\row \i Ctrl+Z \i Undoes the last operation.
+\row \i Ctrl+Y \i Redoes the last operation.
+\row \i LeftArrow \i Moves the cursor one character to the left.
+\row \i Ctrl+LeftArrow \i Moves the cursor one word to the left.
+\row \i RightArrow \i Moves the cursor one character to the right.
+\row \i Ctrl+RightArrow \i Moves the cursor one word to the right.
+\row \i UpArrow \i Moves the cursor one line up.
+\row \i Ctrl+UpArrow \i Moves the cursor one word up.
+\row \i DownArrow \i Moves the cursor one line down.
+\row \i Ctrl+Down Arrow \i Moves the cursor one word down.
+\row \i PageUp \i Moves the cursor one page up.
+\row \i PageDown \i Moves the cursor one page down.
+\row \i Home \i Moves the cursor to the beginning of the line.
+\row \i Ctrl+Home \i Moves the cursor to the beginning of the text.
+\row \i End \i Moves the cursor to the end of the line.
+\row \i Ctrl+End \i Moves the cursor to the end of the text.
+\row \i Alt+Wheel \i Scrolls the page horizontally (the Wheel is the mouse wheel).
+\row \i Ctrl+Wheel \i Zooms the text.
+\endtable
+To select (mark) text hold down the Shift key whilst pressing one
+of the movement keystrokes, for example, \e{Shift+Right Arrow}
+will select the character to the right, and \e{Shift+Ctrl+Right
+Arrow} will select the word to the right, etc.
+\section1 Differences to QTextEdit
+QPlainTextEdit is a thin class, implemented by using most of the
+technology that is behind QTextEdit and QTextDocument. Its
+performance benefits over QTextEdit stem mostly from using a
+different and simplified text layout called
+QPlainTextDocumentLayout on the text document (see
+QTextDocument::setDocumentLayout()). The plain text document layout
+does not support tables nor embedded frames, and \e{replaces a
+pixel-exact height calculation with a line-by-line respectively
+paragraph-by-paragraph scrolling approach}. This makes it possible
+to handle significantly larger documents, and still resize the
+editor with line wrap enabled in real time. It also makes for a
+fast log viewer (see setMaximumBlockCount()).
+\sa QTextDocument, QTextCursor, {Application Example},
+{Code Editor Example}, {Syntax Highlighter Example},
+{Rich Text Processing}
+*/
+/*!
+\property QPlainTextEdit::plainText
+This property gets and sets the plain text editor's contents. The previous
+contents are removed and undo/redo history is reset when this property is set.
+By default, for an editor with no contents, this property contains an empty string.
+*/
+/*!
+\property QPlainTextEdit::undoRedoEnabled
+\brief whether undo and redo are enabled
+Users are only able to undo or redo actions if this property is
+true, and if there is an action that can be undone (or redone).
+By default, this property is true.
+*/
+/*!
+\enum QPlainTextEdit::LineWrapMode
+\value NoWrap
+\value WidgetWidth
+*/
+/*!
+Constructs an empty QPlainTextEdit with parent \a
+parent.
+*/
+QPlainTextEdit::QPlainTextEdit(QWidget *parent)
+: QAbstractScrollArea(*new QPlainTextEditPrivate, parent)
+{
+Q_D(QPlainTextEdit);
+d->init();
+}
+/*!
+\internal
+*/
+QPlainTextEdit::QPlainTextEdit(QPlainTextEditPrivate &dd, QWidget *parent)
+: QAbstractScrollArea(dd, parent)
+{
+Q_D(QPlainTextEdit);
+d->init();
+}
+/*!
+Constructs a QPlainTextEdit with parent \a parent. The text edit will display
+the plain text \a text.
+*/
+QPlainTextEdit::QPlainTextEdit(const QString &text, QWidget *parent)
+: QAbstractScrollArea(*new QPlainTextEditPrivate, parent)
+{
+Q_D(QPlainTextEdit);
+d->init(text);
+}
+/*!
+Destructor.
+*/
+QPlainTextEdit::~QPlainTextEdit()
+{
+Q_D(QPlainTextEdit);
+if (d->documentLayoutPtr) {
+if (d->documentLayoutPtr->priv()->mainViewPrivate == d)
+d->documentLayoutPtr->priv()->mainViewPrivate = 0;
+}
+}
+/*!
+Makes \a document the new document of the text editor.
+The parent QObject of the provided document remains the owner
+of the object. If the current document is a child of the text
+editor, then it is deleted.
+The document must have a document layout that inherits
+QPlainTextDocumentLayout (see QTextDocument::setDocumentLayout()).
+\sa document()
+*/
+void QPlainTextEdit::setDocument(QTextDocument *document)
+{
+Q_D(QPlainTextEdit);
+QPlainTextDocumentLayout *documentLayout = 0;
+if (!document) {
+document = new QTextDocument(d->control);
+documentLayout = new QPlainTextDocumentLayout(document);
+document->setDocumentLayout(documentLayout);
+} else {
+documentLayout = qobject_cast<QPlainTextDocumentLayout*>(document->documentLayout());
+if (!documentLayout) {
+qWarning("QPlainTextEdit::setDocument: Document set does not support QPlainTextDocumentLayout");
+return;
+}
+}
+d->control->setDocument(document);
+if (!documentLayout->priv()->mainViewPrivate)
+documentLayout->priv()->mainViewPrivate = d;
+d->documentLayoutPtr = documentLayout;
+d->updateDefaultTextOption();
+d->relayoutDocument();
+d->_q_adjustScrollbars();
+}
+/*!
+Returns a pointer to the underlying document.
+\sa setDocument()
+*/
+QTextDocument *QPlainTextEdit::document() const
+{
+Q_D(const QPlainTextEdit);
+return d->control->document();
+}
+/*!
+Sets the visible \a cursor.
+*/
+void QPlainTextEdit::setTextCursor(const QTextCursor &cursor)
+{
+Q_D(QPlainTextEdit);
+d->control->setTextCursor(cursor);
+}
+/*!
+Returns a copy of the QTextCursor that represents the currently visible cursor.
+Note that changes on the returned cursor do not affect QPlainTextEdit's cursor; use
+setTextCursor() to update the visible cursor.
+*/
+QTextCursor QPlainTextEdit::textCursor() const
+{
+Q_D(const QPlainTextEdit);
+return d->control->textCursor();
+}
+/*!
+Undoes the last operation.
+If there is no operation to undo, i.e. there is no undo step in
+the undo/redo history, nothing happens.
+\sa redo()
+*/
+void QPlainTextEdit::undo()
+{
+Q_D(QPlainTextEdit);
+d->control->undo();
+}
+void QPlainTextEdit::redo()
+{
+Q_D(QPlainTextEdit);
+d->control->redo();
+}
+/*!
+\fn void QPlainTextEdit::redo()
+Redoes the last operation.
+If there is no operation to redo, i.e. there is no redo step in
+the undo/redo history, nothing happens.
+\sa undo()
+*/
+#ifndef QT_NO_CLIPBOARD
+/*!
+Copies the selected text to the clipboard and deletes it from
+the text edit.
+If there is no selected text nothing happens.
+\sa copy() paste()
+*/
+void QPlainTextEdit::cut()
+{
+Q_D(QPlainTextEdit);
+d->control->cut();
+}
+/*!
+Copies any selected text to the clipboard.
+\sa copyAvailable()
+*/
+void QPlainTextEdit::copy()
+{
+Q_D(QPlainTextEdit);
+d->control->copy();
+}
+/*!
+Pastes the text from the clipboard into the text edit at the
+current cursor position.
+If there is no text in the clipboard nothing happens.
+To change the behavior of this function, i.e. to modify what
+QPlainTextEdit can paste and how it is being pasted, reimplement the
+virtual canInsertFromMimeData() and insertFromMimeData()
+functions.
+\sa cut() copy()
+*/
+void QPlainTextEdit::paste()
+{
+Q_D(QPlainTextEdit);
+d->control->paste();
+}
+#endif
+/*!
+Deletes all the text in the text edit.
+Note that the undo/redo history is cleared by this function.
+\sa cut() setPlainText()
+*/
+void QPlainTextEdit::clear()
+{
+Q_D(QPlainTextEdit);
+// clears and sets empty content
+d->control->topBlock = d->topLine = 0;
+d->control->clear();
+}
+/*!
+Selects all text.
+\sa copy() cut() textCursor()
+*/
+void QPlainTextEdit::selectAll()
+{
+Q_D(QPlainTextEdit);
+d->control->selectAll();
+}
+/*! \internal
+*/
+bool QPlainTextEdit::event(QEvent *e)
+{
+Q_D(QPlainTextEdit);
+#ifndef QT_NO_CONTEXTMENU
+if (e->type() == QEvent::ContextMenu
+&& static_cast<QContextMenuEvent *>(e)->reason() == QContextMenuEvent::Keyboard) {
+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;
+}
+#endif // QT_NO_CONTEXTMENU
+if (e->type() == QEvent::ShortcutOverride
+|| e->type() == QEvent::ToolTip) {
+d->sendControlEvent(e);
+}
+#ifdef QT_KEYPAD_NAVIGATION
+else if (e->type() == QEvent::EnterEditFocus || e->type() == QEvent::LeaveEditFocus) {
+if (QApplication::keypadNavigationEnabled())
+d->sendControlEvent(e);
+}
+#endif
+else if (e->type() == QEvent::Gesture) {
+QGestureEvent *ge = static_cast<QGestureEvent *>(e);
+QPanGesture *g = static_cast<QPanGesture *>(ge->gesture(Qt::PanGesture));
+if (g) {
+QScrollBar *hBar = horizontalScrollBar();
+QScrollBar *vBar = verticalScrollBar();
+if (g->state() == Qt::GestureStarted)
+d->originalOffsetY = vBar->value();
+QPointF offset = g->offset();
+if (!offset.isNull()) {
+if (QApplication::isRightToLeft())
+offset.rx() *= -1;
+// QPlainTextEdit scrolls by lines only in vertical direction
+QFontMetrics fm(document()->defaultFont());
+int lineHeight = fm.height();
+int newX = hBar->value() - g->delta().x();
+int newY = d->originalOffsetY - offset.y()/lineHeight;
+hBar->setValue(newX);
+vBar->setValue(newY);
+}
+}
+return true;
+}
+return QAbstractScrollArea::event(e);
+}
+/*! \internal
+*/
+void QPlainTextEdit::timerEvent(QTimerEvent *e)
+{
+Q_D(QPlainTextEdit);
+if (e->timerId() == d->autoScrollTimer.timerId()) {
+QRect visible = d->viewport->rect();
+QPoint pos;
+if (d->inDrag) {
+pos = d->autoScrollDragPos;
+visible.adjust(qMin(visible.width()/3,20), qMin(visible.height()/3,20),
+-qMin(visible.width()/3,20), -qMin(visible.height()/3,20));
+} else {
+const QPoint globalPos = QCursor::pos();
+pos = d->viewport->mapFromGlobal(globalPos);
+QMouseEvent ev(QEvent::MouseMove, pos, globalPos, Qt::LeftButton, Qt::LeftButton, Qt::NoModifier);
+mouseMoveEvent(&ev);
+}
+int deltaY = qMax(pos.y() - visible.top(), visible.bottom() - pos.y()) - visible.height();
+int deltaX = qMax(pos.x() - visible.left(), visible.right() - pos.x()) - visible.width();
+int delta = qMax(deltaX, deltaY);
+if (delta >= 0) {
+if (delta < 7)
+delta = 7;
+int timeout = 4900 / (delta * delta);
+d->autoScrollTimer.start(timeout, this);
+if (deltaY > 0)
+d->vbar->triggerAction(pos.y() < visible.center().y() ?
+QAbstractSlider::SliderSingleStepSub
+: QAbstractSlider::SliderSingleStepAdd);
+if (deltaX > 0)
+d->hbar->triggerAction(pos.x() < visible.center().x() ?
+QAbstractSlider::SliderSingleStepSub
+: QAbstractSlider::SliderSingleStepAdd);
+}
+}
+#ifdef QT_KEYPAD_NAVIGATION
+else if (e->timerId() == d->deleteAllTimer.timerId()) {
+d->deleteAllTimer.stop();
+clear();
+}
+#endif
+}
+/*!
+Changes the text of the text edit to the string \a text.
+Any previous text is removed.
+\a text is interpreted as plain text.
+Note that the undo/redo history is cleared by this function.
+\sa toText()
+*/
+void QPlainTextEdit::setPlainText(const QString &text)
+{
+Q_D(QPlainTextEdit);
+d->control->setPlainText(text);
+}
+/*!
+\fn QString QPlainTextEdit::toPlainText() const
+Returns the text of the text edit as plain text.
+\sa QPlainTextEdit::setPlainText()
+*/
+/*! \reimp
+*/
+void QPlainTextEdit::keyPressEvent(QKeyEvent *e)
+{
+Q_D(QPlainTextEdit);
+#ifdef QT_KEYPAD_NAVIGATION
+switch (e->key()) {
+case Qt::Key_Select:
+if (QApplication::keypadNavigationEnabled()) {
+if (!(d->control->textInteractionFlags() & Qt::LinksAccessibleByKeyboard))
+setEditFocus(!hasEditFocus());
+else {
+if (!hasEditFocus())
+setEditFocus(true);
+else {
+QTextCursor cursor = d->control->textCursor();
+QTextCharFormat charFmt = cursor.charFormat();
+if (!cursor.hasSelection() || charFmt.anchorHref().isEmpty()) {
+setEditFocus(false);
+}
+}
+}
+}
+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
+#ifndef QT_NO_SHORTCUT
+Qt::TextInteractionFlags tif = d->control->textInteractionFlags();
+if (tif & Qt::TextSelectableByKeyboard){
+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;
+}
+}
+if (tif & (Qt::TextSelectableByKeyboard | Qt::TextEditable)) {
+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;
+}
+}
+if (!(tif & 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;
+}
+#endif // QT_NO_SHORTCUT
+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_Left:
+case Qt::Key_Right:
+if (QApplication::keypadNavigationEnabled()
+&& QApplication::navigationMode() == Qt::NavigationModeKeypadDirectional) {
+// Same as for Key_Up and Key_Down.
+e->ignore();
+return;
+}
+break;
+case Qt::Key_Back:
+if (!e->isAutoRepeat()) {
+if (QApplication::keypadNavigationEnabled()) {
+if (document()->isEmpty()) {
+setEditFocus(false);
+e->accept();
+} else if (!d->deleteAllTimer.isActive()) {
+e->accept();
+d->deleteAllTimer.start(750, this);
+}
+} else {
+e->ignore();
+return;
+}
+}
+break;
+default: break;
+}
+}
+#endif
+}
+/*! \reimp
+*/
+void QPlainTextEdit::keyReleaseEvent(QKeyEvent *e)
+{
+#ifdef QT_KEYPAD_NAVIGATION
+Q_D(QPlainTextEdit);
+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
+}
+/*!
+Loads the resource specified by the given \a type and \a name.
+This function is an extension of QTextDocument::loadResource().
+\sa QTextDocument::loadResource()
+*/
+QVariant QPlainTextEdit::loadResource(int type, const QUrl &name)
+{
+Q_UNUSED(type);
+Q_UNUSED(name);
+return QVariant();
+}
+/*! \reimp
+*/
+void QPlainTextEdit::resizeEvent(QResizeEvent *e)
+{
+Q_D(QPlainTextEdit);
+if (e->oldSize().width() != e->size().width())
+d->relayoutDocument();
+d->_q_adjustScrollbars();
+}
+void QPlainTextEditPrivate::relayoutDocument()
+{
+QTextDocument *doc = control->document();
+QPlainTextDocumentLayout *documentLayout = qobject_cast<QPlainTextDocumentLayout*>(doc->documentLayout());
+Q_ASSERT(documentLayout);
+documentLayoutPtr = documentLayout;
+int width = viewport->width();
+if (documentLayout->priv()->mainViewPrivate == 0
+|| documentLayout->priv()->mainViewPrivate == this
+|| width > documentLayout->textWidth()) {
+documentLayout->priv()->mainViewPrivate = this;
+documentLayout->setTextWidth(width);
+}
+}
+static void fillBackground(QPainter *p, const QRectF &rect, QBrush brush, QRectF gradientRect = QRectF())
+{
+p->save();
+if (brush.style() >= Qt::LinearGradientPattern && brush.style() <= Qt::ConicalGradientPattern) {
+if (!gradientRect.isNull()) {
+QTransform m = QTransform::fromTranslate(gradientRect.left(), gradientRect.top());
+m.scale(gradientRect.width(), gradientRect.height());
+brush.setTransform(m);
+const_cast<QGradient *>(brush.gradient())->setCoordinateMode(QGradient::LogicalMode);
+}
+} else {
+p->setBrushOrigin(rect.topLeft());
+}
+p->fillRect(rect, brush);
+p->restore();
+}
+/*! \reimp
+*/
+void QPlainTextEdit::paintEvent(QPaintEvent *e)
+{
+QPainter painter(viewport());
+Q_ASSERT(qobject_cast<QPlainTextDocumentLayout*>(document()->documentLayout()));
+QPointF offset(contentOffset());
+QRect er = e->rect();
+QRect viewportRect = viewport()->rect();
+bool editable = !isReadOnly();
+QTextBlock block = firstVisibleBlock();
+qreal maximumWidth = document()->documentLayout()->documentSize().width();
+// Set a brush origin so that the WaveUnderline knows where the wave started
+painter.setBrushOrigin(offset);
+// keep right margin clean from full-width selection
+int maxX = offset.x() + qMax((qreal)viewportRect.width(), maximumWidth)
+- document()->documentMargin();
+er.setRight(qMin(er.right(), maxX));
+painter.setClipRect(er);
+QAbstractTextDocumentLayout::PaintContext context = getPaintContext();
+while (block.isValid()) {
+QRectF r = blockBoundingRect(block).translated(offset);
+QTextLayout *layout = block.layout();
+if (!block.isVisible()) {
+offset.ry() += r.height();
+block = block.next();
+continue;
+}
+if (r.bottom() >= er.top() && r.top() <= er.bottom()) {
+QTextBlockFormat blockFormat = block.blockFormat();
+QBrush bg = blockFormat.background();
+if (bg != Qt::NoBrush) {
+QRectF contentsRect = r;
+contentsRect.setWidth(qMax(r.width(), maximumWidth));
+fillBackground(&painter, contentsRect, bg);
+}
+QVector<QTextLayout::FormatRange> selections;
+int blpos = block.position();
+int bllen = block.length();
+for (int i = 0; i < context.selections.size(); ++i) {
+const QAbstractTextDocumentLayout::Selection &range = context.selections.at(i);
+const int selStart = range.cursor.selectionStart() - blpos;
+const int selEnd = range.cursor.selectionEnd() - blpos;
+if (selStart < bllen && selEnd > 0
+&& selEnd > selStart) {
+QTextLayout::FormatRange o;
+o.start = selStart;
+o.length = selEnd - selStart;
+o.format = range.format;
+selections.append(o);
+} else if (!range.cursor.hasSelection() && range.format.hasProperty(QTextFormat::FullWidthSelection)
+&& block.contains(range.cursor.position())) {
+// for full width selections we don't require an actual selection, just
+// a position to specify the line. that's more convenience in usage.
+QTextLayout::FormatRange o;
+QTextLine l = layout->lineForTextPosition(range.cursor.position() - blpos);
+o.start = l.textStart();
+o.length = l.textLength();
+if (o.start + o.length == bllen - 1)
+++o.length; // include newline
+o.format = range.format;
+selections.append(o);
+}
+}
+bool drawCursor = (editable
+&& context.cursorPosition >= blpos
+&& context.cursorPosition < blpos + bllen);
+bool drawCursorAsBlock = drawCursor && overwriteMode() ;
+if (drawCursorAsBlock) {
+if (context.cursorPosition == blpos + bllen - 1) {
+drawCursorAsBlock = false;
+} else {
+QTextLayout::FormatRange o;
+o.start = context.cursorPosition - blpos;
+o.length = 1;
+o.format.setForeground(palette().base());
+o.format.setBackground(palette().text());
+selections.append(o);
+}
+}
+layout->draw(&painter, offset, selections, er);
+if ((drawCursor && !drawCursorAsBlock)
+|| (editable && context.cursorPosition < -1
+&& !layout->preeditAreaText().isEmpty())) {
+int cpos = context.cursorPosition;
+if (cpos < -1)
+cpos = layout->preeditAreaPosition() - (cpos + 2);
+else
+cpos -= blpos;
+layout->drawCursor(&painter, offset, cpos, cursorWidth());
+}
+}
+offset.ry() += r.height();
+if (offset.y() > viewportRect.height())
+break;
+block = block.next();
+}
+if (backgroundVisible() && !block.isValid() && offset.y() <= er.bottom()
+&& (centerOnScroll() || verticalScrollBar()->maximum() == verticalScrollBar()->minimum())) {
+painter.fillRect(QRect(QPoint((int)er.left(), (int)offset.y()), er.bottomRight()), palette().background());
+}
+}
+void QPlainTextEditPrivate::updateDefaultTextOption()
+{
+QTextDocument *doc = control->document();
+QTextOption opt = doc->defaultTextOption();
+QTextOption::WrapMode oldWrapMode = opt.wrapMode();
+if (lineWrap == QPlainTextEdit::NoWrap)
+opt.setWrapMode(QTextOption::NoWrap);
+else
+opt.setWrapMode(wordWrap);
+if (opt.wrapMode() != oldWrapMode)
+doc->setDefaultTextOption(opt);
+}
+/*! \reimp
+*/
+void QPlainTextEdit::mousePressEvent(QMouseEvent *e)
+{
+Q_D(QPlainTextEdit);
+#ifdef QT_KEYPAD_NAVIGATION
+if (QApplication::keypadNavigationEnabled() && !hasEditFocus())
+setEditFocus(true);
+#endif
+d->sendControlEvent(e);
+}
+/*! \reimp
+*/
+void QPlainTextEdit::mouseMoveEvent(QMouseEvent *e)
+{
+Q_D(QPlainTextEdit);
+d->inDrag = false; // paranoia
+const QPoint pos = e->pos();
+d->sendControlEvent(e);
+if (!(e->buttons() & Qt::LeftButton))
+return;
+QRect visible = d->viewport->rect();
+if (visible.contains(pos))
+d->autoScrollTimer.stop();
+else if (!d->autoScrollTimer.isActive())
+d->autoScrollTimer.start(100, this);
+}
+/*! \reimp
+*/
+void QPlainTextEdit::mouseReleaseEvent(QMouseEvent *e)
+{
+Q_D(QPlainTextEdit);
+d->sendControlEvent(e);
+if (d->autoScrollTimer.isActive()) {
+d->autoScrollTimer.stop();
+d->ensureCursorVisible();
+}
+if (!isReadOnly() && rect().contains(e->pos()))
+d->handleSoftwareInputPanel(e->button(), d->clickCausedFocus);
+d->clickCausedFocus = 0;
+}
+/*! \reimp
+*/
+void QPlainTextEdit::mouseDoubleClickEvent(QMouseEvent *e)
+{
+Q_D(QPlainTextEdit);
+d->sendControlEvent(e);
+}
+/*! \reimp
+*/
+bool QPlainTextEdit::focusNextPrevChild(bool next)
+{
+Q_D(const QPlainTextEdit);
+if (!d->tabChangesFocus && d->control->textInteractionFlags() & Qt::TextEditable)
+return false;
+return QAbstractScrollArea::focusNextPrevChild(next);
+}
+#ifndef QT_NO_CONTEXTMENU
+/*!
+\fn void QPlainTextEdit::contextMenuEvent(QContextMenuEvent *event)
+Shows the standard context menu created with createStandardContextMenu().
+If you do not want the text edit to have a context menu, you can set
+its \l contextMenuPolicy to Qt::NoContextMenu. If you want to
+customize the context menu, reimplement this function. If you want
+to extend the standard context menu, reimplement this function, call
+createStandardContextMenu() and extend the menu returned.
+Information about the event is passed in the \a event object.
+\snippet doc/src/snippets/code/src_gui_widgets_qplaintextedit.cpp 0
+*/
+void QPlainTextEdit::contextMenuEvent(QContextMenuEvent *e)
+{
+Q_D(QPlainTextEdit);
+d->sendControlEvent(e);
+}
+#endif // QT_NO_CONTEXTMENU
+#ifndef QT_NO_DRAGANDDROP
+/*! \reimp
+*/
+void QPlainTextEdit::dragEnterEvent(QDragEnterEvent *e)
+{
+Q_D(QPlainTextEdit);
+d->inDrag = true;
+d->sendControlEvent(e);
+}
+/*! \reimp
+*/
+void QPlainTextEdit::dragLeaveEvent(QDragLeaveEvent *e)
+{
+Q_D(QPlainTextEdit);
+d->inDrag = false;
+d->autoScrollTimer.stop();
+d->sendControlEvent(e);
+}
+/*! \reimp
+*/
+void QPlainTextEdit::dragMoveEvent(QDragMoveEvent *e)
+{
+Q_D(QPlainTextEdit);
+d->autoScrollDragPos = e->pos();
+if (!d->autoScrollTimer.isActive())
+d->autoScrollTimer.start(100, this);
+d->sendControlEvent(e);
+}
+/*! \reimp
+*/
+void QPlainTextEdit::dropEvent(QDropEvent *e)
+{
+Q_D(QPlainTextEdit);
+d->inDrag = false;
+d->autoScrollTimer.stop();
+d->sendControlEvent(e);
+}
+#endif // QT_NO_DRAGANDDROP
+/*! \reimp
+*/
+void QPlainTextEdit::inputMethodEvent(QInputMethodEvent *e)
+{
+Q_D(QPlainTextEdit);
+#ifdef QT_KEYPAD_NAVIGATION
+if (d->control->textInteractionFlags() & Qt::TextEditable
+&& QApplication::keypadNavigationEnabled()
+&& !hasEditFocus()) {
+setEditFocus(true);
+selectAll();    // so text is replaced rather than appended to
+}
+#endif
+d->sendControlEvent(e);
+ensureCursorVisible();
+}
+/*!\reimp
+*/
+void QPlainTextEdit::scrollContentsBy(int dx, int /*dy*/)
+{
+Q_D(QPlainTextEdit);
+d->setTopLine(d->vbar->value(), dx);
+}
+/*!\reimp
+*/
+QVariant QPlainTextEdit::inputMethodQuery(Qt::InputMethodQuery property) const
+{
+Q_D(const QPlainTextEdit);
+QVariant v = d->control->inputMethodQuery(property);
+const QPoint offset(-d->horizontalOffset(), -0);
+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;
+}
+/*! \reimp
+*/
+void QPlainTextEdit::focusInEvent(QFocusEvent *e)
+{
+Q_D(QPlainTextEdit);
+if (e->reason() == Qt::MouseFocusReason) {
+d->clickCausedFocus = 1;
+}
+QAbstractScrollArea::focusInEvent(e);
+d->sendControlEvent(e);
+}
+/*! \reimp
+*/
+void QPlainTextEdit::focusOutEvent(QFocusEvent *e)
+{
+Q_D(QPlainTextEdit);
+QAbstractScrollArea::focusOutEvent(e);
+d->sendControlEvent(e);
+}
+/*! \reimp
+*/
+void QPlainTextEdit::showEvent(QShowEvent *)
+{
+Q_D(QPlainTextEdit);
+if (d->showCursorOnInitialShow) {
+d->showCursorOnInitialShow = false;
+ensureCursorVisible();
+}
+}
+/*! \reimp
+*/
+void QPlainTextEdit::changeEvent(QEvent *e)
+{
+Q_D(QPlainTextEdit);
+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());
+} else if (e->type() == QEvent::LayoutDirectionChange) {
+d->sendControlEvent(e);
+}
+}
+/*! \reimp
+*/
+#ifndef QT_NO_WHEELEVENT
+void QPlainTextEdit::wheelEvent(QWheelEvent *e)
+{
+QAbstractScrollArea::wheelEvent(e);
+updateMicroFocus();
+}
+#endif
+#ifndef QT_NO_CONTEXTMENU
+/*!  This function creates the standard context menu which is shown
+when the user clicks on the line edit with the right mouse
+button. It is called from the default contextMenuEvent() handler.
+The popup menu's ownership is transferred to the caller.
+*/
+QMenu *QPlainTextEdit::createStandardContextMenu()
+{
+Q_D(QPlainTextEdit);
+return d->control->createStandardContextMenu(QPointF(), this);
+}
+#endif // QT_NO_CONTEXTMENU
+/*!
+returns a QTextCursor at position \a pos (in viewport coordinates).
+*/
+QTextCursor QPlainTextEdit::cursorForPosition(const QPoint &pos) const
+{
+Q_D(const QPlainTextEdit);
+return d->control->cursorForPosition(d->mapToContents(pos));
+}
+/*!
+returns a rectangle (in viewport coordinates) that includes the
+\a cursor.
+*/
+QRect QPlainTextEdit::cursorRect(const QTextCursor &cursor) const
+{
+Q_D(const QPlainTextEdit);
+if (cursor.isNull())
+return QRect();
+QRect r = d->control->cursorRect(cursor).toRect();
+r.translate(-d->horizontalOffset(),-d->verticalOffset());
+return r;
+}
+/*!
+returns a rectangle (in viewport coordinates) that includes the
+cursor of the text edit.
+*/
+QRect QPlainTextEdit::cursorRect() const
+{
+Q_D(const QPlainTextEdit);
+QRect r = d->control->cursorRect().toRect();
+r.translate(-d->horizontalOffset(),-d->verticalOffset());
+return r;
+}
+/*!
+\property QPlainTextEdit::overwriteMode
+\brief whether text entered by the user will overwrite existing text
+As with many text editors, the plain text editor widget can be configured
+to insert or overwrite existing text with new text entered by the user.
+If this property is true, existing text is overwritten, character-for-character
+by new text; otherwise, text is inserted at the cursor position, displacing
+existing text.
+By default, this property is false (new text does not overwrite existing text).
+*/
+bool QPlainTextEdit::overwriteMode() const
+{
+Q_D(const QPlainTextEdit);
+return d->control->overwriteMode();
+}
+void QPlainTextEdit::setOverwriteMode(bool overwrite)
+{
+Q_D(QPlainTextEdit);
+d->control->setOverwriteMode(overwrite);
+}
+/*!
+\property QPlainTextEdit::tabStopWidth
+\brief the tab stop width in pixels
+By default, this property contains a value of 80.
+*/
+int QPlainTextEdit::tabStopWidth() const
+{
+Q_D(const QPlainTextEdit);
+return qRound(d->control->document()->defaultTextOption().tabStop());
+}
+void QPlainTextEdit::setTabStopWidth(int width)
+{
+Q_D(QPlainTextEdit);
+QTextOption opt = d->control->document()->defaultTextOption();
+if (opt.tabStop() == width || width < 0)
+return;
+opt.setTabStop(width);
+d->control->document()->setDefaultTextOption(opt);
+}
+/*!
+\property QPlainTextEdit::cursorWidth
+This property specifies the width of the cursor in pixels. The default value is 1.
+*/
+int QPlainTextEdit::cursorWidth() const
+{
+Q_D(const QPlainTextEdit);
+return d->control->cursorWidth();
+}
+void QPlainTextEdit::setCursorWidth(int width)
+{
+Q_D(QPlainTextEdit);
+d->control->setCursorWidth(width);
+}
+/*!
+This function allows temporarily marking certain regions in the document
+with a given color, specified as \a selections. This can be useful for
+example in a programming editor to mark a whole line of text with a given
+background color to indicate the existence of a breakpoint.
+\sa QTextEdit::ExtraSelection, extraSelections()
+*/
+void QPlainTextEdit::setExtraSelections(const QList<QTextEdit::ExtraSelection> &selections)
+{
+Q_D(QPlainTextEdit);
+d->control->setExtraSelections(selections);
+}
+/*!
+Returns previously set extra selections.
+\sa setExtraSelections()
+*/
+QList<QTextEdit::ExtraSelection> QPlainTextEdit::extraSelections() const
+{
+Q_D(const QPlainTextEdit);
+return d->control->extraSelections();
+}
+/*!
+This function returns a new MIME data object to represent the contents
+of the text edit's current selection. It is called when the selection needs
+to be encapsulated into a new QMimeData object; for example, when a drag
+and drop operation is started, or when data is copied to the clipboard.
+If you reimplement this function, note that the ownership of the returned
+QMimeData object is passed to the caller. The selection can be retrieved
+by using the textCursor() function.
+*/
+QMimeData *QPlainTextEdit::createMimeDataFromSelection() const
+{
+Q_D(const QPlainTextEdit);
+return d->control->QTextControl::createMimeDataFromSelection();
+}
+/*!
+This function returns true if the contents of the MIME data object, specified
+by \a source, can be decoded and inserted into the document. It is called
+for example when during a drag operation the mouse enters this widget and it
+is necessary to determine whether it is possible to accept the drag.
+*/
+bool QPlainTextEdit::canInsertFromMimeData(const QMimeData *source) const
+{
+Q_D(const QPlainTextEdit);
+return d->control->QTextControl::canInsertFromMimeData(source);
+}
+/*!
+This function inserts the contents of the MIME data object, specified
+by \a source, into the text edit at the current cursor position. It is
+called whenever text is inserted as the result of a clipboard paste
+operation, or when the text edit accepts data from a drag and drop
+operation.
+*/
+void QPlainTextEdit::insertFromMimeData(const QMimeData *source)
+{
+Q_D(QPlainTextEdit);
+d->control->QTextControl::insertFromMimeData(source);
+}
+/*!
+\property QPlainTextEdit::readOnly
+\brief whether the text edit is read-only
+In a read-only text edit the user can only navigate through the
+text and select text; modifying the text is not possible.
+This property's default is false.
+*/
+bool QPlainTextEdit::isReadOnly() const
+{
+Q_D(const QPlainTextEdit);
+return !(d->control->textInteractionFlags() & Qt::TextEditable);
+}
+void QPlainTextEdit::setReadOnly(bool ro)
+{
+Q_D(QPlainTextEdit);
+Qt::TextInteractionFlags flags = Qt::NoTextInteraction;
+if (ro) {
+flags = Qt::TextSelectableByMouse;
+} else {
+flags = Qt::TextEditorInteraction;
+}
+setAttribute(Qt::WA_InputMethodEnabled, shouldEnableInputMethod(this));
+d->control->setTextInteractionFlags(flags);
+}
+/*!
+\property QPlainTextEdit::textInteractionFlags
+Specifies how the label should interact with user input if it displays text.
+If the flags contain either Qt::LinksAccessibleByKeyboard or Qt::TextSelectableByKeyboard
+then the focus policy is also automatically set to Qt::ClickFocus.
+The default value depends on whether the QPlainTextEdit is read-only
+or editable, and whether it is a QTextBrowser or not.
+*/
+void QPlainTextEdit::setTextInteractionFlags(Qt::TextInteractionFlags flags)
+{
+Q_D(QPlainTextEdit);
+d->control->setTextInteractionFlags(flags);
+}
+Qt::TextInteractionFlags QPlainTextEdit::textInteractionFlags() const
+{
+Q_D(const QPlainTextEdit);
+return d->control->textInteractionFlags();
+}
+/*!
+Merges the properties specified in \a modifier into the current character
+format by calling QTextCursor::mergeCharFormat on the editor's cursor.
+If the editor has a selection then the properties of \a modifier are
+directly applied to the selection.
+\sa QTextCursor::mergeCharFormat()
+*/
+void QPlainTextEdit::mergeCurrentCharFormat(const QTextCharFormat &modifier)
+{
+Q_D(QPlainTextEdit);
+d->control->mergeCurrentCharFormat(modifier);
+}
+/*!
+Sets the char format that is be used when inserting new text to \a
+format by calling QTextCursor::setCharFormat() on the editor's
+cursor.  If the editor has a selection then the char format is
+directly applied to the selection.
+*/
+void QPlainTextEdit::setCurrentCharFormat(const QTextCharFormat &format)
+{
+Q_D(QPlainTextEdit);
+d->control->setCurrentCharFormat(format);
+}
+/*!
+Returns the char format that is used when inserting new text.
+*/
+QTextCharFormat QPlainTextEdit::currentCharFormat() const
+{
+Q_D(const QPlainTextEdit);
+return d->control->currentCharFormat();
+}
+/*!
+Convenience slot that inserts \a text at the current
+cursor position.
+It is equivalent to
+\snippet doc/src/snippets/code/src_gui_widgets_qplaintextedit.cpp 1
+*/
+void QPlainTextEdit::insertPlainText(const QString &text)
+{
+Q_D(QPlainTextEdit);
+d->control->insertPlainText(text);
+}
+/*!
+Moves the cursor by performing the given \a operation.
+If \a mode is QTextCursor::KeepAnchor, the cursor selects the text it moves over.
+This is the same effect that the user achieves when they hold down the Shift key
+and move the cursor with the cursor keys.
+\sa QTextCursor::movePosition()
+*/
+void QPlainTextEdit::moveCursor(QTextCursor::MoveOperation operation, QTextCursor::MoveMode mode)
+{
+Q_D(QPlainTextEdit);
+d->control->moveCursor(operation, mode);
+}
+/*!
+Returns whether text can be pasted from the clipboard into the textedit.
+*/
+bool QPlainTextEdit::canPaste() const
+{
+Q_D(const QPlainTextEdit);
+return d->control->canPaste();
+}
+#ifndef QT_NO_PRINTER
+/*!
+Convenience function to print the text edit's document to the given \a printer. This
+is equivalent to calling the print method on the document directly except that this
+function also supports QPrinter::Selection as print range.
+\sa QTextDocument::print()
+*/
+void QPlainTextEdit::print(QPrinter *printer) const
+{
+Q_D(const QPlainTextEdit);
+d->control->print(printer);
+}
+#endif // QT _NO_PRINTER
+/*! \property QPlainTextEdit::tabChangesFocus
+\brief whether \gui Tab changes focus or is accepted as input
+In some occasions text edits should not allow the user to input
+tabulators or change indentation using the \gui Tab key, as this breaks
+the focus chain. The default is false.
+*/
+bool QPlainTextEdit::tabChangesFocus() const
+{
+Q_D(const QPlainTextEdit);
+return d->tabChangesFocus;
+}
+void QPlainTextEdit::setTabChangesFocus(bool b)
+{
+Q_D(QPlainTextEdit);
+d->tabChangesFocus = b;
+}
+/*!
+\property QPlainTextEdit::documentTitle
+\brief the title of the document parsed from the text.
+By default, this property contains an empty string.
+*/
+/*!
+\property QPlainTextEdit::lineWrapMode
+\brief the line wrap mode
+The default mode is WidgetWidth which causes words to be
+wrapped at the right edge of the text edit. Wrapping occurs at
+whitespace, keeping whole words intact. If you want wrapping to
+occur within words use setWordWrapMode().
+*/
+QPlainTextEdit::LineWrapMode QPlainTextEdit::lineWrapMode() const
+{
+Q_D(const QPlainTextEdit);
+return d->lineWrap;
+}
+void QPlainTextEdit::setLineWrapMode(LineWrapMode wrap)
+{
+Q_D(QPlainTextEdit);
+if (d->lineWrap == wrap)
+return;
+d->lineWrap = wrap;
+d->updateDefaultTextOption();
+d->relayoutDocument();
+d->_q_adjustScrollbars();
+ensureCursorVisible();
+}
+/*!
+\property QPlainTextEdit::wordWrapMode
+\brief the mode QPlainTextEdit will use when wrapping text by words
+By default, this property is set to QTextOption::WrapAtWordBoundaryOrAnywhere.
+\sa QTextOption::WrapMode
+*/
+QTextOption::WrapMode QPlainTextEdit::wordWrapMode() const
+{
+Q_D(const QPlainTextEdit);
+return d->wordWrap;
+}
+void QPlainTextEdit::setWordWrapMode(QTextOption::WrapMode mode)
+{
+Q_D(QPlainTextEdit);
+if (mode == d->wordWrap)
+return;
+d->wordWrap = mode;
+d->updateDefaultTextOption();
+}
+/*!
+\property QPlainTextEdit::backgroundVisible
+\brief whether the palette background is visible outside the document area
+If set to true, the plain text edit paints the palette background
+on the viewport area not covered by the text document. Otherwise,
+if set to false, it won't. The feature makes it possible for
+the user to visually distinguish between the area of the document,
+painted with the base color of the palette, and the empty
+area not covered by any document.
+The default is false.
+*/
+bool QPlainTextEdit::backgroundVisible() const
+{
+Q_D(const QPlainTextEdit);
+return d->backgroundVisible;
+}
+void QPlainTextEdit::setBackgroundVisible(bool visible)
+{
+Q_D(QPlainTextEdit);
+if (visible == d->backgroundVisible)
+return;
+d->backgroundVisible = visible;
+d->updateViewport();
+}
+/*!
+\property QPlainTextEdit::centerOnScroll
+\brief whether the cursor should be centered on screen
+If set to true, the plain text edit scrolls the document
+vertically to make the cursor visible at the center of the
+viewport. This also allows the text edit to scroll below the end
+of the document. Otherwise, if set to false, the plain text edit
+scrolls the smallest amount possible to ensure the cursor is
+visible.  The same algorithm is applied to any new line appended
+through appendPlainText().
+The default is false.
+\sa centerCursor(), ensureCursorVisible()
+*/
+bool QPlainTextEdit::centerOnScroll() const
+{
+Q_D(const QPlainTextEdit);
+return d->centerOnScroll;
+}
+void QPlainTextEdit::setCenterOnScroll(bool enabled)
+{
+Q_D(QPlainTextEdit);
+if (enabled == d->centerOnScroll)
+return;
+d->centerOnScroll = enabled;
+}
+/*!
+Finds the next occurrence of the string, \a exp, using the given
+\a options. Returns true if \a exp was found and changes the
+cursor to select the match; otherwise returns false.
+*/
+bool QPlainTextEdit::find(const QString &exp, QTextDocument::FindFlags options)
+{
+Q_D(QPlainTextEdit);
+return d->control->find(exp, options);
+}
+/*!
+\fn void QPlainTextEdit::copyAvailable(bool yes)
+This signal is emitted when text is selected or de-selected in the
+text edit.
+When text is selected this signal will be emitted with \a yes set
+to true. If no text has been selected or if the selected text is
+de-selected this signal is emitted with \a yes set to false.
+If \a yes is true then copy() can be used to copy the selection to
+the clipboard. If \a yes is false then copy() does nothing.
+\sa selectionChanged()
+*/
+/*!
+\fn void QPlainTextEdit::selectionChanged()
+This signal is emitted whenever the selection changes.
+\sa copyAvailable()
+*/
+/*!
+\fn void QPlainTextEdit::cursorPositionChanged()
+This signal is emitted whenever the position of the
+cursor changed.
+*/
+/*!
+\fn void QPlainTextEdit::updateRequest(const QRect &rect, int dy)
+This signal is emitted when the text document needs an update of
+the specified \a rect. If the text is scrolled, \a rect will cover
+the entire viewport area. If the text is scrolled vertically, \a
+dy carries the amount of pixels the viewport was scrolled.
+The purpose of the signal is to support extra widgets in plain
+text edit subclasses that e.g. show line numbers, breakpoints, or
+other extra information.
+*/
+/*!  \fn void QPlainTextEdit::blockCountChanged(int newBlockCount);
+This signal is emitted whenever the block count changes. The new
+block count is passed in \a newBlockCount.
+*/
+/*!  \fn void QPlainTextEdit::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.
+*/
+void QPlainTextEditPrivate::append(const QString &text, Qt::TextFormat format)
+{
+Q_Q(QPlainTextEdit);
+QTextDocument *document = control->document();
+QPlainTextDocumentLayout *documentLayout = qobject_cast<QPlainTextDocumentLayout*>(document->documentLayout());
+Q_ASSERT(documentLayout);
+int maximumBlockCount = document->maximumBlockCount();
+if (maximumBlockCount)
+document->setMaximumBlockCount(0);
+const bool atBottom =  q->isVisible()
+&& (control->blockBoundingRect(document->lastBlock()).bottom() - verticalOffset()
+<= viewport->rect().bottom());
+if (!q->isVisible())
+showCursorOnInitialShow = true;
+bool documentSizeChangedBlocked = documentLayout->priv()->blockDocumentSizeChanged;
+documentLayout->priv()->blockDocumentSizeChanged = true;
+if (format == Qt::RichText)
+control->appendHtml(text);
+else if (format == Qt::PlainText)
+control->appendPlainText(text);
+else
+control->append(text);
+if (maximumBlockCount > 0) {
+if (document->blockCount() > maximumBlockCount) {
+bool blockUpdate = false;
+if (control->topBlock) {
+control->topBlock--;
+blockUpdate = true;
+emit q->updateRequest(viewport->rect(), 0);
+}
+bool updatesBlocked = documentLayout->priv()->blockUpdate;
+documentLayout->priv()->blockUpdate = blockUpdate;
+QTextCursor cursor(document);
+cursor.movePosition(QTextCursor::NextBlock, QTextCursor::KeepAnchor);
+cursor.removeSelectedText();
+documentLayout->priv()->blockUpdate = updatesBlocked;
+}
+document->setMaximumBlockCount(maximumBlockCount);
+}
+documentLayout->priv()->blockDocumentSizeChanged = documentSizeChangedBlocked;
+_q_adjustScrollbars();
+if (atBottom) {
+const bool needScroll =  !centerOnScroll
+|| control->blockBoundingRect(document->lastBlock()).bottom() - verticalOffset()
+> viewport->rect().bottom();
+if (needScroll)
+vbar->setValue(vbar->maximum());
+}
+}
+/*!
+Appends a new paragraph with \a text to the end of the text edit.
+\sa appendHtml()
+*/
+void QPlainTextEdit::appendPlainText(const QString &text)
+{
+Q_D(QPlainTextEdit);
+d->append(text, Qt::PlainText);
+}
+/*!
+Appends a new paragraph with \a html to the end of the text edit.
+appendPlainText()
+*/
+void QPlainTextEdit::appendHtml(const QString &html)
+{
+Q_D(QPlainTextEdit);
+d->append(html, Qt::RichText);
+}
+void QPlainTextEditPrivate::ensureCursorVisible(bool center)
+{
+Q_Q(QPlainTextEdit);
+QRect visible = viewport->rect();
+QRect cr = q->cursorRect();
+if (cr.top() < visible.top() || cr.bottom() > visible.bottom()) {
+ensureVisible(control->textCursor().position(), center);
+}
+const bool rtl = q->isRightToLeft();
+if (cr.left() < visible.left() || cr.right() > visible.right()) {
+int x = cr.center().x() + horizontalOffset() - visible.width()/2;
+hbar->setValue(rtl ? hbar->maximum() - x : x);
+}
+}
+/*!
+Ensures that the cursor is visible by scrolling the text edit if
+necessary.
+\sa centerCursor(), centerOnScroll
+*/
+void QPlainTextEdit::ensureCursorVisible()
+{
+Q_D(QPlainTextEdit);
+d->ensureCursorVisible(d->centerOnScroll);
+}
+/*!  Scrolls the document in order to center the cursor vertically.
+\sa ensureCursorVisible(), centerOnScroll
+*/
+void QPlainTextEdit::centerCursor()
+{
+Q_D(QPlainTextEdit);
+d->ensureVisible(textCursor().position(), true, true);
+}
+/*!
+Returns the first visible block.
+\sa blockBoundingRect()
+*/
+QTextBlock QPlainTextEdit::firstVisibleBlock() const
+{
+Q_D(const QPlainTextEdit);
+return d->control->firstVisibleBlock();
+}
+/*!  Returns the content's origin in viewport coordinates.
+The origin of the content of a plain text edit is always the top
+left corner of the first visible text block. The content offset
+is different from (0,0) when the text has been scrolled
+horizontally, or when the first visible block has been scrolled
+partially off the screen, i.e. the visible text does not start
+with the first line of the first visible block, or when the first
+visible block is the very first block and the editor displays a
+margin.
+\sa firstVisibleBlock(), horizontalScrollBar(), verticalScrollBar()
+*/
+QPointF QPlainTextEdit::contentOffset() const
+{
+Q_D(const QPlainTextEdit);
+return QPointF(-d->horizontalOffset(), -d->verticalOffset());
+}
+/*!  Returns the bounding rectangle of the text \a block in content
+coordinates. Translate the rectangle with the contentOffset() to get
+visual coordinates on the viewport.
+\sa firstVisibleBlock(), blockBoundingRect()
+*/
+QRectF QPlainTextEdit::blockBoundingGeometry(const QTextBlock &block) const
+{
+Q_D(const QPlainTextEdit);
+return d->control->blockBoundingRect(block);
+}
+/*!
+Returns the bounding rectangle of the text \a block in the block's own coordinates.
+\sa blockBoundingGeometry()
+*/
+QRectF QPlainTextEdit::blockBoundingRect(const QTextBlock &block) const
+{
+QPlainTextDocumentLayout *documentLayout = qobject_cast<QPlainTextDocumentLayout*>(document()->documentLayout());
+Q_ASSERT(documentLayout);
+return documentLayout->blockBoundingRect(block);
+}
+/*!
+\property QPlainTextEdit::blockCount
+\brief the number of text blocks in the document.
+By default, in an empty document, this property contains a value of 1.
+*/
+int QPlainTextEdit::blockCount() const
+{
+return document()->blockCount();
+}
+/*!  Returns the paint context for the viewport(), useful only when
+reimplementing paintEvent().
+*/
+QAbstractTextDocumentLayout::PaintContext QPlainTextEdit::getPaintContext() const
+{
+Q_D(const QPlainTextEdit);
+return d->control->getPaintContext(d->viewport);
+}
+/*!
+\property QPlainTextEdit::maximumBlockCount
+\brief the limit for blocks in the document.
+Specifies the maximum number of blocks the document may have. If there are
+more blocks in the document that specified with this property blocks are removed
+from the beginning of the document.
+A negative or zero value specifies that the document may contain an unlimited
+amount of blocks.
+The default value is 0.
+Note that setting this property will apply the limit immediately to the document
+contents. Setting this property also disables the undo redo history.
+*/
+/*!
+\fn void QPlainTextEdit::textChanged()
+This signal is emitted whenever the document's content changes; for
+example, when text is inserted or deleted, or when formatting is applied.
+*/
+/*!
+\fn void QPlainTextEdit::undoAvailable(bool available)
+This signal is emitted whenever undo operations become available
+(\a available is true) or unavailable (\a available is false).
+*/
+/*!
+\fn void QPlainTextEdit::redoAvailable(bool available)
+This signal is emitted whenever redo operations become available
+(\a available is true) or unavailable (\a available is false).
+*/
+QT_END_NAMESPACE
+#include "moc_qplaintextedit.cpp"
+#include "moc_qplaintextedit_p.cpp"
+#endif // QT_NO_TEXTEDIT