1 files changed, 134 insertions, 0 deletions
diff --git a/tests/manual/textrendering/codeeditor/codeeditor.cpp b/tests/manual/textrendering/codeeditor/codeeditor.cpp
new file mode 100644
index 0000000000..3b7fd58d30
--- /dev/null
+++ b/tests/manual/textrendering/codeeditor/codeeditor.cpp
@@ -0,0 +1,134 @@
+// Copyright (C) 2016 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only
+
+#include "codeeditor.h"
+
+#include <QPainter>
+#include <QTextBlock>
+
+//![constructor]
+
+CodeEditor::CodeEditor(QWidget *parent) : QPlainTextEdit(parent)
+{
+    lineNumberArea = new LineNumberArea(this);
+
+    connect(this, &CodeEditor::blockCountChanged, this, &CodeEditor::updateLineNumberAreaWidth);
+    connect(this, &CodeEditor::updateRequest, this, &CodeEditor::updateLineNumberArea);
+    connect(this, &CodeEditor::cursorPositionChanged, this, &CodeEditor::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().horizontalAdvance(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 = qRound(blockBoundingGeometry(block).translated(contentOffset()).top());
+    int bottom = top + qRound(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 + qRound(blockBoundingRect(block).height());
+        ++blockNumber;
+    }
+}
+//![extraAreaPaintEvent_2]
+