Qt 5.9 | Qt Quick Controls 2 | Qt Quick Controls 2 - Text Editor | documenthandler.cpp Example File

Qt 5.9.2 Reference Documentation

# documenthandler.cpp Example File

texteditor/documenthandler.cpp

      /****************************************************************************
      **
      ** Copyright (C) 2017 The Qt Company Ltd.
      ** Contact: https://www.qt.io/licensing/
      **
      ** This file is part of the examples of the Qt Toolkit.
      **
      ** $QT_BEGIN_LICENSE:BSD$
      ** Commercial License Usage
      ** Licensees holding valid commercial Qt licenses may use this file in
      ** accordance with the commercial license agreement provided with the
      ** Software or, alternatively, in accordance with the terms contained in
      ** a written agreement between you and The Qt Company. For licensing terms
      ** and conditions see https://www.qt.io/terms-conditions. For further
      ** information use the contact form at https://www.qt.io/contact-us.
      **
      ** BSD License Usage
      ** Alternatively, you may use this file under the terms of the BSD license
      ** as follows:
      **
      ** "Redistribution and use in source and binary forms, with or without
      ** modification, are permitted provided that the following conditions are
      ** met:
      **   * Redistributions of source code must retain the above copyright
      **     notice, this list of conditions and the following disclaimer.
      **   * Redistributions in binary form must reproduce the above copyright
      **     notice, this list of conditions and the following disclaimer in
      **     the documentation and/or other materials provided with the
      **     distribution.
      **   * Neither the name of The Qt Company Ltd nor the names of its
      **     contributors may be used to endorse or promote products derived
      **     from this software without specific prior written permission.
      **
      **
      ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
      ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
      ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
      ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
      ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
      ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
      ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
      ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
      ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
      ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
      ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
      **
      ** $QT_END_LICENSE$
      **
      ****************************************************************************/

      #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);
      }