pageselector.cpp Example File

pdfviewer/pageselector.cpp

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  ** Copyright (C) 2017 Klaralvdalens Datakonsult AB (KDAB).
  ** Contact: http://www.qt.io/licensing/
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  ** This file is part of the QtPDF module of the Qt Toolkit.
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  ** Alternatively, this file may be used under the terms of the GNU
  ** General Public License version 2.0 or later as published by the Free
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  #include "pageselector.h"

  #include <QHBoxLayout>
  #include <QLabel>
  #include <QLineEdit>
  #include <QPdfPageNavigation>
  #include <QToolButton>

  PageSelector::PageSelector(QWidget *parent)
      : QWidget(parent)
      , m_pageNavigation(nullptr)
  {
      QHBoxLayout *layout = new QHBoxLayout(this);

      m_previousPageButton = new QToolButton(this);
      m_previousPageButton->setText("<");
      m_previousPageButton->setEnabled(false);

      m_pageNumberEdit = new QLineEdit(this);
      m_pageNumberEdit->setAlignment(Qt::AlignRight);

      m_pageCountLabel = new QLabel(this);
      m_pageCountLabel->setText("0");

      m_nextPageButton = new QToolButton(this);
      m_nextPageButton->setText(">");
      m_nextPageButton->setEnabled(false);

      layout->addWidget(m_previousPageButton);
      layout->addWidget(m_pageNumberEdit);
      layout->addWidget(m_pageCountLabel);
      layout->addWidget(m_nextPageButton);
  }

  void PageSelector::setPageNavigation(QPdfPageNavigation *pageNavigation)
  {
      m_pageNavigation = pageNavigation;

      connect(m_previousPageButton, &QToolButton::clicked, m_pageNavigation, &QPdfPageNavigation::goToPreviousPage);
      connect(m_pageNavigation, &QPdfPageNavigation::canGoToPreviousPageChanged, m_previousPageButton, &QToolButton::setEnabled);

      connect(m_pageNavigation, &QPdfPageNavigation::currentPageChanged, this, &PageSelector::onCurrentPageChanged);
      connect(m_pageNavigation, &QPdfPageNavigation::pageCountChanged, this, [this](int pageCount){ m_pageCountLabel->setText(QString::fromLatin1("/ %1").arg(pageCount)); });

      connect(m_pageNumberEdit, &QLineEdit::editingFinished, this, &PageSelector::pageNumberEdited);

      connect(m_nextPageButton, &QToolButton::clicked, m_pageNavigation, &QPdfPageNavigation::goToNextPage);
      connect(m_pageNavigation, &QPdfPageNavigation::canGoToNextPageChanged, m_nextPageButton, &QToolButton::setEnabled);

      onCurrentPageChanged(m_pageNavigation->currentPage());
  }

  void PageSelector::onCurrentPageChanged(int page)
  {
      if (m_pageNavigation->pageCount() == 0)
          m_pageNumberEdit->setText(QString::number(0));
      else
          m_pageNumberEdit->setText(QString::number(page + 1));
  }

  void PageSelector::pageNumberEdited()
  {
      if (!m_pageNavigation)
          return;

      const QString text = m_pageNumberEdit->text();

      bool ok = false;
      const int pageNumber = text.toInt(&ok);

      if (!ok)
          onCurrentPageChanged(m_pageNavigation->currentPage());
      else
          m_pageNavigation->setCurrentPage(qBound(0, pageNumber - 1, m_pageNavigation->pageCount() - 1));
  }