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);
  }