Move codeeditor to folder

pglab/codeeditor/CodeEditor.cpp

@@ -0,0 +1,272 @@
+#include "CodeEditor.h"
+#include "EditorGutter.h"
+#include <QPainter>
+#include <QTextBlock>
+#include <QDebug>
+//
+// Adapted from codeeditor example
+// http://doc.qt.io/qt-5/qtwidgets-widgets-codeeditor-example.html
+//
+// Used term gutter as I want to expand it to do other things to like error
+// position marking.
+//
+
+CodeEditor::CodeEditor(QWidget *parent)
+	: QPlainTextEdit(parent)
+	, gutterArea(new EditorGutter(this))
+{
+	connect(this, SIGNAL(blockCountChanged(int)), this, SLOT(updateGutterAreaWidth(int)));
+	connect(this, SIGNAL(updateRequest(QRect,int)), this, SLOT(updateGutterArea(QRect,int)));
+	connect(this, SIGNAL(cursorPositionChanged()), this, SLOT(highlightCurrentLine()));
+	connect(this, SIGNAL(textChanged()), this, SLOT(onTextChanged()));
+
+	setWordWrapMode(QTextOption::NoWrap);
+
+	updateGutterAreaWidth(0);
+	setTabSize(4);
+	highlightCurrentLine();
+}
+
+int CodeEditor::gutterAreaWidth()
+{
+	int digits = 1;
+	int max = qMax(1, blockCount());
+	while (max >= 10) {
+		max /= 10;
+		++digits;
+	}
+
+	int space = 3 + fontMetrics().horizontalAdvance(QLatin1Char('9')) * (digits + 2);
+
+	return space;
+}
+
+void CodeEditor::updateGutterAreaWidth(int /* newBlockCount */)
+{
+	setViewportMargins(gutterAreaWidth(), 0, 0, 0);
+}
+
+void CodeEditor::updateGutterArea(const QRect &rect, int dy)
+{
+	if (dy)
+		gutterArea->scroll(0, dy);
+	else
+		gutterArea->update(0, rect.y(), gutterArea->width(), rect.height());
+
+	if (rect.contains(viewport()->rect()))
+		updateGutterAreaWidth(0);
+}
+
+void CodeEditor::resizeEvent(QResizeEvent *e)
+{
+	QPlainTextEdit::resizeEvent(e);
+
+	QRect cr = contentsRect();
+	gutterArea->setGeometry(QRect(cr.left(), cr.top(), gutterAreaWidth(), cr.height()));
+}
+
+void CodeEditor::highlightCurrentLine()
+{
+	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();
+	currentLine = selection;
+
+	updateExtraSelections();
+}
+
+void CodeEditor::onTextChanged()
+{
+	clearErrorMarkers();
+}
+
+void CodeEditor::addErrorMarker(int position, int length)
+{
+	QTextEdit::ExtraSelection selection;
+	QColor lineColor = QColor(Qt::red).lighter(160);
+	selection.format.setBackground(lineColor);
+	selection.format.setFontItalic(true);
+	selection.cursor = textCursor();
+	selection.cursor.setPosition(position);
+	int lineno = selection.cursor.blockNumber();
+	errorLines.insert(lineno);
+	selection.cursor.movePosition(QTextCursor::Right, QTextCursor::KeepAnchor, length);
+	errorMarkers.append(selection);
+
+	update();
+
+	updateExtraSelections();
+}
+
+void CodeEditor::clearErrorMarkers()
+{
+	errorMarkers.clear();
+	errorLines.clear();
+	update();
+	updateExtraSelections();
+}
+
+void CodeEditor::updateExtraSelections()
+{
+	QList<QTextEdit::ExtraSelection> extraSelections;
+	extraSelections.append(currentLine);
+	for (auto&& e : errorMarkers)
+		extraSelections.append(e);
+
+	setExtraSelections(extraSelections);
+}
+
+void CodeEditor::gutterAreaPaintEvent(QPaintEvent *event)
+{
+	QPainter painter(gutterArea);
+	painter.fillRect(event->rect(), Qt::lightGray);
+
+	QTextBlock block = firstVisibleBlock();
+	int blockNumber = block.blockNumber();
+	int top = (int) blockBoundingGeometry(block).translated(contentOffset()).top();
+	int bottom = top + (int) blockBoundingRect(block).height();
+
+	// We will now loop through all visible lines and paint the line numbers in the
+	// extra area for each line. Notice that in a plain text edit each line will
+	// consist of one QTextBlock; though, if line wrapping is enabled, a line may span
+	// several rows in the text edit's viewport.
+	//
+	// We get the top and bottom y-coordinate of the first text block, and adjust these
+	// values by the height of the current text block in each iteration in the loop.
+	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, gutterArea->width(), fontMetrics().height(),
+							 Qt::AlignRight, number);
+
+			if (errorLines.count(blockNumber) > 0) {
+				int s = fontMetrics().height() - 8;
+				painter.setBrush(QBrush(Qt::red));
+				painter.drawEllipse(4, top + 4, s, s);
+			}
+		}
+
+		block = block.next();
+		top = bottom;
+		bottom = top + (int) blockBoundingRect(block).height();
+		++blockNumber;
+	}
+}
+
+void CodeEditor::keyPressEvent(QKeyEvent *e)
+{
+	auto k = e->key();
+	if (k == Qt::Key_Tab) {
+		// Function returns false if there was no selection to indent
+		if (indentSelection(true))
+			return;
+	}
+	else if (k == Qt::Key_Backtab) {
+		// Function returns false if there was no selection to indent
+		if (indentSelection(false))
+			return;
+	}
+	else if (k == Qt::Key_Equal || k == Qt::Key_Plus) {
+		if (e->modifiers().testFlag(Qt::ControlModifier)) {
+			auto f = font();
+			f.setPointSize(f.pointSize() + 1);
+			setFont(f);
+		}
+	}
+	else if (k == Qt::Key_Minus) {
+		if (e->modifiers().testFlag(Qt::ControlModifier)) {
+			auto f = font();
+			f.setPointSize(f.pointSize() - 1);
+			setFont(f);
+		}
+	}
+	QPlainTextEdit::keyPressEvent(e);
+}
+
+bool CodeEditor::indentSelection(bool indent)
+{
+	auto cursor = textCursor();
+
+	if(!cursor.hasSelection())
+		return false;
+
+	auto first_pos = cursor.anchor();
+	auto end_pos   = cursor.position();
+
+	if(first_pos > end_pos)
+		std::swap(first_pos, end_pos);
+
+	cursor.setPosition(first_pos, QTextCursor::MoveAnchor);
+	auto start_block = cursor.block().blockNumber();
+
+	cursor.setPosition(end_pos, QTextCursor::MoveAnchor);
+	auto end_block = cursor.block().blockNumber();
+	if (end_block == start_block)
+		return false;
+
+	cursor.beginEditBlock();
+	cursor.setPosition(first_pos, QTextCursor::MoveAnchor);
+	const auto block_count = end_block - start_block;
+	for(int block = 0; block <= block_count; ++block) {
+		cursor.movePosition(QTextCursor::StartOfBlock, QTextCursor::MoveAnchor);
+		if (indent) {
+			if (m_useTab)
+				cursor.insertText("\t");
+			else
+				cursor.insertText(QString(m_tabSize, ' '));
+		}
+		else {
+			// remove tab if there is a tab
+			cursor.movePosition(QTextCursor::EndOfLine, QTextCursor::KeepAnchor);
+			const QString text = cursor.selectedText();
+			int index = 0;
+			int pos = 0;
+			while (pos < m_tabSize && index < text.length()) {
+				QChar c = text[index++];
+				if (c == ' ')
+					++pos;
+				else if (c == '\t')
+					pos = ((pos + m_tabSize) / m_tabSize) * m_tabSize;
+				else {
+					--index;
+					break;
+				}
+			}
+			cursor.movePosition(QTextCursor::StartOfBlock, QTextCursor::MoveAnchor);
+			for (int i = 0; i < index; ++i)
+				cursor.movePosition(QTextCursor::Right, QTextCursor::KeepAnchor);
+			cursor.removeSelectedText();
+		}
+		cursor.movePosition(QTextCursor::NextBlock, QTextCursor::MoveAnchor);
+	}
+	cursor.endEditBlock();
+
+	cursor.setPosition(first_pos, QTextCursor::MoveAnchor);
+	cursor.movePosition(QTextCursor::StartOfBlock, QTextCursor::MoveAnchor);
+	while(cursor.block().blockNumber() < end_block)
+		cursor.movePosition(QTextCursor::NextBlock, QTextCursor::KeepAnchor);
+
+	cursor.movePosition(QTextCursor::EndOfBlock, QTextCursor::KeepAnchor);
+
+	setTextCursor(cursor);
+	return true;
+}
+
+void CodeEditor::setFont(const QFont &f)
+{
+	QWidget::setFont(f);
+	auto orig_tab = m_tabSize;
+	m_tabSize = 0;
+	setTabSize(orig_tab);
+}
+
+void CodeEditor::setTabSize(int chars)
+{
+	m_tabSize = chars;
+	int pixels = fontMetrics().horizontalAdvance(QString(chars, '0'));
+	this->setTabStopDistance(pixels);
+}

pglab/codeeditor/CodeEditor.h

@@ -0,0 +1,55 @@
+#ifndef CODEEDITOR_H
+#define CODEEDITOR_H
+
+#include <QPlainTextEdit>
+#include <set>
+
+/** This class adds some capabilities to QPlainTextEdit that are useful
+ * in code editor scenarios.
+ */
+class CodeEditor : public QPlainTextEdit
+{
+	Q_OBJECT
+public:
+	explicit CodeEditor(QWidget *parent = nullptr);
+
+	void gutterAreaPaintEvent(QPaintEvent *event);
+	int gutterAreaWidth();
+
+	void addErrorMarker(int position, int length);
+	void clearErrorMarkers();
+	void setFont(const QFont &);
+	void setTabSize(int chars);
+protected:
+	void resizeEvent(QResizeEvent *event) override;
+	void keyPressEvent(QKeyEvent *e) override;
+
+signals:
+
+public slots:
+
+private slots:
+	void updateGutterAreaWidth(int newBlockCount);
+	void highlightCurrentLine();
+	void updateGutterArea(const QRect &, int);
+	void onTextChanged();
+
+
+private:
+	QWidget *gutterArea;
+
+	QTextEdit::ExtraSelection currentLine;
+	QList<QTextEdit::ExtraSelection> errorMarkers;
+
+	std::set<int> errorLines;
+
+	// Settings
+	int m_tabSize = 0;  // tabSize in characters
+	bool m_useTab = false;
+
+	void updateExtraSelections();
+	bool indentSelection(bool indent);
+
+};
+
+#endif // CODEEDITOR_H

pglab/codeeditor/EditorGutter.cpp

@@ -0,0 +1,19 @@
+#include "EditorGutter.h"
+#include "CodeEditor.h"
+
+EditorGutter::EditorGutter(CodeEditor *editor)
+	: QWidget(editor)
+	, codeEditor(editor)
+{
+
+}
+
+QSize EditorGutter::sizeHint() const
+{
+	return QSize(codeEditor->gutterAreaWidth(), 0);
+}
+
+void EditorGutter::paintEvent(QPaintEvent *event)
+{
+	codeEditor->gutterAreaPaintEvent(event);
+}

pglab/codeeditor/EditorGutter.h

@@ -0,0 +1,28 @@
+#ifndef EDITORGUTTER_H
+#define EDITORGUTTER_H
+
+#include <QWidget>
+//#include <QPlainTextEdit>
+
+class CodeEditor;
+
+class EditorGutter : public QWidget
+{
+	Q_OBJECT
+public:
+	explicit EditorGutter(CodeEditor *editor);
+
+	QSize sizeHint() const override;
+
+protected:
+
+	void paintEvent(QPaintEvent *event) override;
+
+private:
+	CodeEditor *codeEditor;
+signals:
+
+public slots:
+};
+
+#endif // EDITORGUTTER_H