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Diffstat (limited to 'examples/widgets/codeeditor/codeeditor.cpp')
-rw-r--r-- | examples/widgets/codeeditor/codeeditor.cpp | 171 |
1 files changed, 171 insertions, 0 deletions
diff --git a/examples/widgets/codeeditor/codeeditor.cpp b/examples/widgets/codeeditor/codeeditor.cpp new file mode 100644 index 0000000..b855c7a --- /dev/null +++ b/examples/widgets/codeeditor/codeeditor.cpp @@ -0,0 +1,171 @@ +/**************************************************************************** +** +** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies). +** Contact: Qt Software Information (qt-info@nokia.com) +** +** This file is part of the examples 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 either Technology Preview License Agreement or the +** Beta Release License Agreement. +** +** 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 1.0, included in the file LGPL_EXCEPTION.txt in this +** package. +** +** GNU General Public License Usage +** Alternatively, this file may be used under the terms of the GNU +** General Public License version 3.0 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 the GNU General Public License version 3.0 requirements will be +** met: http://www.gnu.org/copyleft/gpl.html. +** +** If you are unsure which license is appropriate for your use, please +** contact the sales department at qt-sales@nokia.com. +** $QT_END_LICENSE$ +** +****************************************************************************/ + +#include <QtGui> + +#include <codeeditor.h> + +//![constructor] + +CodeEditor::CodeEditor(QWidget *parent) : QPlainTextEdit(parent) +{ + lineNumberArea = new LineNumberArea(this); + + connect(this, SIGNAL(blockCountChanged(int)), this, SLOT(updateLineNumberAreaWidth(int))); + connect(this, SIGNAL(updateRequest(const QRect &, int)), this, SLOT(updateLineNumberArea(const QRect &, int))); + connect(this, SIGNAL(cursorPositionChanged()), this, SLOT(highlightCurrentLine())); + + updateLineNumberAreaWidth(0); + highlightCurrentLine(); +} + +//![constructor] + +//![extraAreaWidth] + +int CodeEditor::lineNumberAreaWidth() +{ + int digits = 1; + int max = qMax(1, blockCount()); + while (max >= 10) { + max /= 10; + ++digits; + } + + int space = 3 + fontMetrics().width(QLatin1Char('9')) * digits; + + return space; +} + +//![extraAreaWidth] + +//![slotUpdateExtraAreaWidth] + +void CodeEditor::updateLineNumberAreaWidth(int /* newBlockCount */) +{ + setViewportMargins(lineNumberAreaWidth(), 0, 0, 0); +} + +//![slotUpdateExtraAreaWidth] + +//![slotUpdateRequest] + +void CodeEditor::updateLineNumberArea(const QRect &rect, int dy) +{ + if (dy) + lineNumberArea->scroll(0, dy); + else + lineNumberArea->update(0, rect.y(), lineNumberArea->width(), rect.height()); + + if (rect.contains(viewport()->rect())) + updateLineNumberAreaWidth(0); +} + +//![slotUpdateRequest] + +//![resizeEvent] + +void CodeEditor::resizeEvent(QResizeEvent *e) +{ + QPlainTextEdit::resizeEvent(e); + + QRect cr = contentsRect(); + lineNumberArea->setGeometry(QRect(cr.left(), cr.top(), lineNumberAreaWidth(), cr.height())); +} + +//![resizeEvent] + +//![cursorPositionChanged] + +void CodeEditor::highlightCurrentLine() +{ + QList<QTextEdit::ExtraSelection> extraSelections; + + if (!isReadOnly()) { + QTextEdit::ExtraSelection selection; + + QColor lineColor = QColor(Qt::yellow).lighter(160); + + selection.format.setBackground(lineColor); + selection.format.setProperty(QTextFormat::FullWidthSelection, true); + selection.cursor = textCursor(); + selection.cursor.clearSelection(); + extraSelections.append(selection); + } + + setExtraSelections(extraSelections); +} + +//![cursorPositionChanged] + +//![extraAreaPaintEvent_0] + +void CodeEditor::lineNumberAreaPaintEvent(QPaintEvent *event) +{ + QPainter painter(lineNumberArea); + painter.fillRect(event->rect(), Qt::lightGray); + +//![extraAreaPaintEvent_0] + +//![extraAreaPaintEvent_1] + QTextBlock block = firstVisibleBlock(); + int blockNumber = block.blockNumber(); + int top = (int) blockBoundingGeometry(block).translated(contentOffset()).top(); + int bottom = top + (int) blockBoundingRect(block).height(); +//![extraAreaPaintEvent_1] + +//![extraAreaPaintEvent_2] + while (block.isValid() && top <= event->rect().bottom()) { + if (block.isVisible() && bottom >= event->rect().top()) { + QString number = QString::number(blockNumber + 1); + painter.setPen(Qt::black); + painter.drawText(0, top, lineNumberArea->width(), fontMetrics().height(), + Qt::AlignRight, number); + } + + block = block.next(); + top = bottom; + bottom = top + (int) blockBoundingRect(block).height(); + ++blockNumber; + } +} +//![extraAreaPaintEvent_2] + |