documenthandler.cpp Example File

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 #include "documenthandler.h"

 #include <QFile>
 #include <QFileInfo>
 #include <QFileSelector>
 #include <QQmlFile>
 #include <QQmlFileSelector>
 #include <QQuickTextDocument>
 #include <QTextCharFormat>
 #include <QTextCodec>
 #include <QTextDocument>
 #include <QDebug>

 DocumentHandler::DocumentHandler(QObject *parent)
     : QObject(parent)
     , m_document(nullptr)
     , m_cursorPosition(-1)
     , m_selectionStart(0)
     , m_selectionEnd(0)
 {
 }

 QQuickTextDocument *DocumentHandler::document() const
 {
     return m_document;
 }

 void DocumentHandler::setDocument(QQuickTextDocument *document)
 {
     if (document == m_document)
         return;

     m_document = document;
     emit documentChanged();
 }

 int DocumentHandler::cursorPosition() const
 {
     return m_cursorPosition;
 }

 void DocumentHandler::setCursorPosition(int position)
 {
     if (position == m_cursorPosition)
         return;

     m_cursorPosition = position;
     reset();
     emit cursorPositionChanged();
 }

 int DocumentHandler::selectionStart() const
 {
     return m_selectionStart;
 }

 void DocumentHandler::setSelectionStart(int position)
 {
     if (position == m_selectionStart)
         return;

     m_selectionStart = position;
     emit selectionStartChanged();
 }

 int DocumentHandler::selectionEnd() const
 {
     return m_selectionEnd;
 }

 void DocumentHandler::setSelectionEnd(int position)
 {
     if (position == m_selectionEnd)
         return;

     m_selectionEnd = position;
     emit selectionEndChanged();
 }

 QString DocumentHandler::fontFamily() const
 {
     QTextCursor cursor = textCursor();
     if (cursor.isNull())
         return QString();
     QTextCharFormat format = cursor.charFormat();
     return format.font().family();
 }

 void DocumentHandler::setFontFamily(const QString &family)
 {
     QTextCharFormat format;
     format.setFontFamily(family);
     mergeFormatOnWordOrSelection(format);
     emit fontFamilyChanged();
 }

 QColor DocumentHandler::textColor() const
 {
     QTextCursor cursor = textCursor();
     if (cursor.isNull())
         return QColor(Qt::black);
     QTextCharFormat format = cursor.charFormat();
     return format.foreground().color();
 }

 void DocumentHandler::setTextColor(const QColor &color)
 {
     QTextCharFormat format;
     format.setForeground(QBrush(color));
     mergeFormatOnWordOrSelection(format);
     emit textColorChanged();
 }

 Qt::Alignment DocumentHandler::alignment() const
 {
     QTextCursor cursor = textCursor();
     if (cursor.isNull())
         return Qt::AlignLeft;
     return textCursor().blockFormat().alignment();
 }

 void DocumentHandler::setAlignment(Qt::Alignment alignment)
 {
     QTextBlockFormat format;
     format.setAlignment(alignment);
     QTextCursor cursor = textCursor();
     cursor.mergeBlockFormat(format);
     emit alignmentChanged();
 }

 bool DocumentHandler::bold() const
 {
     QTextCursor cursor = textCursor();
     if (cursor.isNull())
         return false;
     return textCursor().charFormat().fontWeight() == QFont::Bold;
 }

 void DocumentHandler::setBold(bool bold)
 {
     QTextCharFormat format;
     format.setFontWeight(bold ? QFont::Bold : QFont::Normal);
     mergeFormatOnWordOrSelection(format);
     emit boldChanged();
 }

 bool DocumentHandler::italic() const
 {
     QTextCursor cursor = textCursor();
     if (cursor.isNull())
         return false;
     return textCursor().charFormat().fontItalic();
 }

 void DocumentHandler::setItalic(bool italic)
 {
     QTextCharFormat format;
     format.setFontItalic(italic);
     mergeFormatOnWordOrSelection(format);
     emit italicChanged();
 }

 bool DocumentHandler::underline() const
 {
     QTextCursor cursor = textCursor();
     if (cursor.isNull())
         return false;
     return textCursor().charFormat().fontUnderline();
 }

 void DocumentHandler::setUnderline(bool underline)
 {
     QTextCharFormat format;
     format.setFontUnderline(underline);
     mergeFormatOnWordOrSelection(format);
     emit underlineChanged();
 }

 int DocumentHandler::fontSize() const
 {
     QTextCursor cursor = textCursor();
     if (cursor.isNull())
         return 0;
     QTextCharFormat format = cursor.charFormat();
     return format.font().pointSize();
 }

 void DocumentHandler::setFontSize(int size)
 {
     if (size <= 0)
         return;

     QTextCursor cursor = textCursor();
     if (cursor.isNull())
         return;

     if (!cursor.hasSelection())
         cursor.select(QTextCursor::WordUnderCursor);

     if (cursor.charFormat().property(QTextFormat::FontPointSize).toInt() == size)
         return;

     QTextCharFormat format;
     format.setFontPointSize(size);
     mergeFormatOnWordOrSelection(format);
     emit fontSizeChanged();
 }

 QString DocumentHandler::fileName() const
 {
     const QString filePath = QQmlFile::urlToLocalFileOrQrc(m_fileUrl);
     const QString fileName = QFileInfo(filePath).fileName();
     if (fileName.isEmpty())
         return QStringLiteral("untitled.txt");
     return fileName;
 }

 QString DocumentHandler::fileType() const
 {
     return QFileInfo(fileName()).suffix();
 }

 QUrl DocumentHandler::fileUrl() const
 {
     return m_fileUrl;
 }

 void DocumentHandler::load(const QUrl &fileUrl)
 {
     if (fileUrl == m_fileUrl)
         return;

     QQmlEngine *engine = qmlEngine(this);
     if (!engine) {
         qWarning() << "load() called before DocumentHandler has QQmlEngine";
         return;
     }

     const QUrl path = QQmlFileSelector::get(engine)->selector()->select(fileUrl);
     const QString fileName = QQmlFile::urlToLocalFileOrQrc(path);
     if (QFile::exists(fileName)) {
         QFile file(fileName);
         if (file.open(QFile::ReadOnly)) {
             QByteArray data = file.readAll();
             QTextCodec *codec = QTextCodec::codecForHtml(data);
             if (QTextDocument *doc = textDocument())
                 doc->setModified(false);

             emit loaded(codec->toUnicode(data));
             reset();
         }
     }

     m_fileUrl = fileUrl;
     emit fileUrlChanged();
 }

 void DocumentHandler::saveAs(const QUrl &fileUrl)
 {
     QTextDocument *doc = textDocument();
     if (!doc)
         return;

     const QString filePath = fileUrl.toLocalFile();
     const bool isHtml = QFileInfo(filePath).suffix().contains(QLatin1String("htm"));
     QFile file(filePath);
     if (!file.open(QFile::WriteOnly | QFile::Truncate | (isHtml ? QFile::NotOpen : QFile::Text))) {
         emit error(tr("Cannot save: ") + file.errorString());
         return;
     }
     file.write((isHtml ? doc->toHtml() : doc->toPlainText()).toUtf8());
     file.close();

     if (fileUrl == m_fileUrl)
         return;

     m_fileUrl = fileUrl;
     emit fileUrlChanged();
 }

 void DocumentHandler::reset()
 {
     emit fontFamilyChanged();
     emit alignmentChanged();
     emit boldChanged();
     emit italicChanged();
     emit underlineChanged();
     emit fontSizeChanged();
     emit textColorChanged();
 }

 QTextCursor DocumentHandler::textCursor() const
 {
     QTextDocument *doc = textDocument();
     if (!doc)
         return QTextCursor();

     QTextCursor cursor = QTextCursor(doc);
     if (m_selectionStart != m_selectionEnd) {
         cursor.setPosition(m_selectionStart);
         cursor.setPosition(m_selectionEnd, QTextCursor::KeepAnchor);
     } else {
         cursor.setPosition(m_cursorPosition);
     }
     return cursor;
 }

 QTextDocument *DocumentHandler::textDocument() const
 {
     if (!m_document)
         return nullptr;

     return m_document->textDocument();
 }

 void DocumentHandler::mergeFormatOnWordOrSelection(const QTextCharFormat &format)
 {
     QTextCursor cursor = textCursor();
     if (!cursor.hasSelection())
         cursor.select(QTextCursor::WordUnderCursor);
     cursor.mergeCharFormat(format);
 }