Port pdfviewer example to QPdfView widget

Change-Id: Id651a2c179628506f0955751abda57cbae569ee9
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>

10 files changed, 311 insertions, 479 deletions

diff --git a/examples/pdf/pdfviewer/mainwindow.cpp b/examples/pdf/pdfviewer/mainwindow.cpp
index fd26563..5f9bf38 100644
--- a/examples/pdf/pdfviewer/mainwindow.cpp
+++ b/examples/pdf/pdfviewer/mainwindow.cpp
@@ -37,14 +37,14 @@
 #include "mainwindow.h"
 #include "ui_mainwindow.h"
 
-#include "sequentialpagewidget.h"
+#include "pageselector.h"
+#include "zoomselector.h"
 
 #include <QFileDialog>
-#include <QLineEdit>
 #include <QMessageBox>
 #include <QPdfBookmarkModel>
 #include <QPdfDocument>
-#include <QScroller>
+#include <QPdfPageNavigation>
 #include <QtMath>
 
 const qreal zoomMultiplier = qSqrt(2.0);
@@ -54,27 +54,23 @@ Q_LOGGING_CATEGORY(lcExample, "qt.examples.pdfviewer")
 MainWindow::MainWindow(QWidget *parent)
     : QMainWindow(parent)
     , ui(new Ui::MainWindow)
-    , m_pageWidget(new SequentialPageWidget(this))
-    , m_zoomEdit(new QLineEdit(this))
-    , m_pageEdit(new QLineEdit(this))
+    , m_zoomSelector(new ZoomSelector(this))
+    , m_pageSelector(new PageSelector(this))
     , m_document(new QPdfDocument(this))
 {
     ui->setupUi(this);
-    ui->scrollArea->setWidget(m_pageWidget);
-    m_zoomEdit->setMaximumWidth(50);
-    m_zoomEdit->setAlignment(Qt::AlignHCenter);
-    ui->mainToolBar->insertWidget(ui->actionZoom_In, m_zoomEdit);
-    m_pageEdit->setMaximumWidth(50);
-    m_pageEdit->setAlignment(Qt::AlignHCenter);
-    ui->mainToolBar->insertWidget(ui->actionGo, m_pageEdit);
-    connect(m_pageWidget, SIGNAL(showingPageRange(int,int)),
-            this, SLOT(showingPageRange(int,int)), Qt::QueuedConnection);
-    connect(m_pageWidget, SIGNAL(zoomChanged(qreal)),
-            this, SLOT(zoomChanged(qreal)));
-    connect(m_zoomEdit, SIGNAL(returnPressed()), this, SLOT(zoomEdited()));
-    connect(m_pageEdit, SIGNAL(returnPressed()), this, SLOT(on_actionGo_triggered()));
-
-    QScroller::grabGesture(ui->scrollArea);
+
+    m_zoomSelector->setMaximumWidth(150);
+    ui->mainToolBar->insertWidget(ui->actionZoom_In, m_zoomSelector);
+
+    m_pageSelector->setMaximumWidth(150);
+    ui->mainToolBar->addWidget(m_pageSelector);
+
+    m_pageSelector->setPageNavigation(ui->pdfView->pageNavigation());
+
+    connect(m_zoomSelector, &ZoomSelector::zoomModeChanged, ui->pdfView, &QPdfView::setZoomMode);
+    connect(m_zoomSelector, &ZoomSelector::zoomFactorChanged, ui->pdfView, &QPdfView::setZoomFactor);
+    m_zoomSelector->reset();
 
     QPdfBookmarkModel *bookmarkModel = new QPdfBookmarkModel(this);
     bookmarkModel->setDocument(m_document);
@@ -84,7 +80,10 @@ MainWindow::MainWindow(QWidget *parent)
 
     ui->tabWidget->setTabEnabled(1, false); // disable 'Pages' tab for now
 
-    m_pageWidget->setDocument(m_document);
+    ui->pdfView->setDocument(m_document);
+
+    connect(ui->pdfView, &QPdfView::zoomFactorChanged,
+            m_zoomSelector, &ZoomSelector::setZoomFactor);
 }
 
 MainWindow::~MainWindow()
@@ -103,30 +102,6 @@ void MainWindow::open(const QUrl &docLocation)
         QMessageBox::critical(this, tr("Failed to open"), tr("%1 is not a valid local file").arg(docLocation.toString()));
     }
     qCDebug(lcExample) << docLocation;
-    ui->scrollArea->ensureVisible(0, 0, 0, 0);
-}
-
-void MainWindow::showingPageRange(int start, int end)
-{
-    ui->statusBar->clearMessage();
-    if (start == end)
-        ui->statusBar->showMessage(tr("showing page %1").arg(start));
-    else
-        ui->statusBar->showMessage(tr("showing pages %1 to %2").arg(start).arg(end));
-    m_pageEdit->setText(QString::number(end));
-}
-
-void MainWindow::zoomChanged(qreal factor)
-{
-    m_zoomEdit->setText(tr("%1%").arg(factor * 100., 0, 'f', 0));
-}
-
-void MainWindow::zoomEdited()
-{
-    bool ok = false;
-    qreal factor = m_zoomEdit->text().remove(QChar('%')).toDouble(&ok);
-    if (ok)
-        m_pageWidget->setZoom(factor / 100.);
 }
 
 void MainWindow::bookmarkSelected(const QModelIndex &index)
@@ -135,7 +110,7 @@ void MainWindow::bookmarkSelected(const QModelIndex &index)
         return;
 
     const int page = index.data(QPdfBookmarkModel::PageNumberRole).toInt();
-    ui->scrollArea->ensureVisible(0, m_pageWidget->yForPage(page));
+    ui->pdfView->pageNavigation()->setCurrentPage(page);
 }
 
 void MainWindow::on_actionOpen_triggered()
@@ -163,28 +138,25 @@ void MainWindow::on_actionAbout_Qt_triggered()
 
 void MainWindow::on_actionZoom_In_triggered()
 {
-    m_pageWidget->setZoom(m_pageWidget->zoom() * zoomMultiplier);
+    ui->pdfView->setZoomFactor(ui->pdfView->zoomFactor() * zoomMultiplier);
 }
 
 void MainWindow::on_actionZoom_Out_triggered()
 {
-    m_pageWidget->setZoom(m_pageWidget->zoom() / zoomMultiplier);
+    ui->pdfView->setZoomFactor(ui->pdfView->zoomFactor() / zoomMultiplier);
 }
 
-void MainWindow::on_actionGo_triggered()
+void MainWindow::on_actionPrevious_Page_triggered()
 {
-    bool ok = false;
-    int page = m_pageEdit->text().toInt(&ok);
-    if (!ok) return;
-    ui->scrollArea->ensureVisible(0, m_pageWidget->yForPage(page));
+    ui->pdfView->pageNavigation()->goToPreviousPage();
 }
 
-void MainWindow::on_actionPrevious_Page_triggered()
+void MainWindow::on_actionNext_Page_triggered()
 {
-    ui->scrollArea->ensureVisible(0, m_pageWidget->yForPage(m_pageWidget->topPageShowing() - 1));
+    ui->pdfView->pageNavigation()->goToNextPage();
 }
 
-void MainWindow::on_actionNext_Page_triggered()
+void MainWindow::on_actionContinuous_triggered()
 {
-    ui->scrollArea->ensureVisible(0, m_pageWidget->yForPage(m_pageWidget->bottomPageShowing() + 1));
+    ui->pdfView->setPageMode(ui->actionContinuous->isChecked() ? QPdfView::MultiPage : QPdfView::SinglePage);
 }
diff --git a/examples/pdf/pdfviewer/mainwindow.h b/examples/pdf/pdfviewer/mainwindow.h
index f292058..afdfcad 100644
--- a/examples/pdf/pdfviewer/mainwindow.h
+++ b/examples/pdf/pdfviewer/mainwindow.h
@@ -47,11 +47,12 @@ namespace Ui {
 class MainWindow;
 }
 
-class QLineEdit;
 class QPdfDocument;
+class QPdfView;
 QT_END_NAMESPACE
 
-class SequentialPageWidget;
+class PageSelector;
+class ZoomSelector;
 
 class MainWindow : public QMainWindow
 {
@@ -65,9 +66,6 @@ public slots:
     void open(const QUrl &docLocation);
 
 private slots:
-    void showingPageRange(int start, int end);
-    void zoomChanged(qreal factor);
-    void zoomEdited();
     void bookmarkSelected(const QModelIndex &index);
 
     // action handlers
@@ -77,15 +75,14 @@ private slots:
     void on_actionAbout_Qt_triggered();
     void on_actionZoom_In_triggered();
     void on_actionZoom_Out_triggered();
-    void on_actionGo_triggered();
     void on_actionPrevious_Page_triggered();
     void on_actionNext_Page_triggered();
+    void on_actionContinuous_triggered();
 
 private:
     Ui::MainWindow *ui;
-    SequentialPageWidget *m_pageWidget;
-    QLineEdit *m_zoomEdit;
-    QLineEdit *m_pageEdit;
+    ZoomSelector *m_zoomSelector;
+    PageSelector *m_pageSelector;
 
     QPdfDocument *m_document;
 };
diff --git a/examples/pdf/pdfviewer/mainwindow.ui b/examples/pdf/pdfviewer/mainwindow.ui
index 738cef4..2651525 100644
--- a/examples/pdf/pdfviewer/mainwindow.ui
+++ b/examples/pdf/pdfviewer/mainwindow.ui
@@ -113,26 +113,13 @@
            </attribute>
           </widget>
          </widget>
-         <widget class="QScrollArea" name="scrollArea">
+         <widget class="QPdfView" name="pdfView" native="true">
           <property name="sizePolicy">
            <sizepolicy hsizetype="Expanding" vsizetype="Expanding">
             <horstretch>10</horstretch>
             <verstretch>0</verstretch>
            </sizepolicy>
           </property>
-          <property name="widgetResizable">
-           <bool>true</bool>
-          </property>
-          <widget class="QWidget" name="scrollAreaWidgetContents">
-           <property name="geometry">
-            <rect>
-             <x>0</x>
-             <y>0</y>
-             <width>401</width>
-             <height>515</height>
-            </rect>
-           </property>
-          </widget>
          </widget>
         </widget>
        </item>
@@ -172,6 +159,8 @@
     <addaction name="actionZoom_Out"/>
     <addaction name="actionPrevious_Page"/>
     <addaction name="actionNext_Page"/>
+    <addaction name="separator"/>
+    <addaction name="actionContinuous"/>
    </widget>
    <addaction name="menuFile"/>
    <addaction name="menuView"/>
@@ -195,7 +184,6 @@
    <addaction name="actionZoom_Out"/>
    <addaction name="actionZoom_In"/>
    <addaction name="separator"/>
-   <addaction name="actionGo"/>
   </widget>
   <widget class="QStatusBar" name="statusBar"/>
   <action name="actionOpen">
@@ -252,14 +240,6 @@
     <string>Ctrl+-</string>
    </property>
   </action>
-  <action name="actionGo">
-   <property name="text">
-    <string>Go</string>
-   </property>
-   <property name="toolTip">
-    <string>Go to Page</string>
-   </property>
-  </action>
   <action name="actionPrevious_Page">
    <property name="text">
     <string>Previous Page</string>
@@ -276,8 +256,24 @@
     <string>PgDown</string>
    </property>
   </action>
+  <action name="actionContinuous">
+   <property name="checkable">
+    <bool>true</bool>
+   </property>
+   <property name="text">
+    <string>Continuous</string>
+   </property>
+  </action>
  </widget>
  <layoutdefault spacing="6" margin="11"/>
+ <customwidgets>
+  <customwidget>
+   <class>QPdfView</class>
+   <extends>QWidget</extends>
+   <header location="global">qpdfview.h</header>
+   <container>1</container>
+  </customwidget>
+ </customwidgets>
  <resources>
   <include location="resources.qrc"/>
  </resources>
diff --git a/examples/pdf/pdfviewer/pagerenderer.cpp b/examples/pdf/pdfviewer/pagerenderer.cpp
deleted file mode 100644
index 8cb1ed6..0000000
--- a/examples/pdf/pdfviewer/pagerenderer.cpp
+++ /dev/null
@@ -1,105 +0,0 @@
-/****************************************************************************
-**
-** Copyright (C) 2016 The Qt Company Ltd.
-** Contact: http://www.qt.io/licensing/
-**
-** This file is part of the QtPDF module of the Qt Toolkit.
-**
-** $QT_BEGIN_LICENSE:LGPL3$
-** 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 http://www.qt.io/terms-conditions. For further
-** information use the contact form at http://www.qt.io/contact-us.
-**
-** GNU Lesser General Public License Usage
-** Alternatively, this file may be used under the terms of the GNU Lesser
-** General Public License version 3 as published by the Free Software
-** Foundation and appearing in the file LICENSE.LGPLv3 included in the
-** packaging of this file. Please review the following information to
-** ensure the GNU Lesser General Public License version 3 requirements
-** will be met: https://www.gnu.org/licenses/lgpl.html.
-**
-** GNU General Public License Usage
-** 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
-** Software Foundation and appearing in the file LICENSE.GPL included in
-** the packaging of this file. Please review the following information to
-** ensure the GNU General Public License version 2.0 requirements will be
-** met: http://www.gnu.org/licenses/gpl-2.0.html.
-**
-** $QT_END_LICENSE$
-**
-****************************************************************************/
-
-#include "pagerenderer.h"
-
-#include <QElapsedTimer>
-#include <QLoggingCategory>
-#include <QPainter>
-#include <QPdfDocument>
-#include <QUrl>
-
-Q_DECLARE_LOGGING_CATEGORY(lcExample)
-
-PageRenderer::PageRenderer(QObject *parent)
-    : QThread(parent)
-    , m_document(nullptr)
-    , m_page(0)
-    , m_zoom(1.)
-    , m_minRenderTime(1000000000.)
-    , m_maxRenderTime(0.)
-    , m_totalRenderTime(0.)
-    , m_totalPagesRendered(0)
-{
-}
-
-void PageRenderer::setDocument(QPdfDocument *document)
-{
-    m_document = document;
-}
-
-void PageRenderer::requestPage(int page, qreal zoom, Priority priority)
-{
-    // TODO maybe queue up the requests
-    m_page = page;
-    m_zoom = zoom;
-    start(priority);
-}
-
-void PageRenderer::run()
-{
-    renderPage(m_page, m_zoom);
-}
-
-void PageRenderer::renderPage(int page, qreal zoom)
-{
-    if (!m_document || m_document->status() != QPdfDocument::Ready)
-        return;
-
-    const QSizeF size = m_document->pageSize(page) * m_zoom;
-
-    QElapsedTimer timer;
-    timer.start();
-
-    const QImage &img = m_document->render(page, size.toSize());
-
-    const qreal secs = timer.nsecsElapsed() / 1000000000.0;
-    if (secs < m_minRenderTime)
-        m_minRenderTime = secs;
-
-    if (secs > m_maxRenderTime)
-        m_maxRenderTime = secs;
-
-    m_totalRenderTime += secs;
-    ++m_totalPagesRendered;
-
-    emit pageReady(page, zoom, img);
-
-    qCDebug(lcExample) << "page" << page << "zoom" << m_zoom << "size" << size << "in" << secs <<
-                          "secs; min" << m_minRenderTime <<
-                          "avg" << m_totalRenderTime / m_totalPagesRendered <<
-                          "max" << m_maxRenderTime;
-}
diff --git a/examples/pdf/pdfviewer/pageselector.cpp b/examples/pdf/pdfviewer/pageselector.cpp
new file mode 100644
index 0000000..cd3c4ba
--- /dev/null
+++ b/examples/pdf/pdfviewer/pageselector.cpp
@@ -0,0 +1,111 @@
+/****************************************************************************
+**
+** Copyright (C) 2017 Klaralvdalens Datakonsult AB (KDAB).
+** Contact: http://www.qt.io/licensing/
+**
+** This file is part of the QtPDF module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL3$
+** 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 http://www.qt.io/terms-conditions. For further
+** information use the contact form at http://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPLv3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl.html.
+**
+** GNU General Public License Usage
+** 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
+** Software Foundation and appearing in the file LICENSE.GPL included in
+** the packaging of this file. Please review the following information to
+** ensure the GNU General Public License version 2.0 requirements will be
+** met: http://www.gnu.org/licenses/gpl-2.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#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));
+}
diff --git a/examples/pdf/pdfviewer/pagerenderer.h b/examples/pdf/pdfviewer/pageselector.h
index f1e4918..7a7283f 100644
--- a/examples/pdf/pdfviewer/pagerenderer.h
+++ b/examples/pdf/pdfviewer/pageselector.h
@@ -1,6 +1,6 @@
 /****************************************************************************
 **
-** Copyright (C) 2016 The Qt Company Ltd.
+** Copyright (C) 2017 Klaralvdalens Datakonsult AB (KDAB).
 ** Contact: http://www.qt.io/licensing/
 **
 ** This file is part of the QtPDF module of the Qt Toolkit.
@@ -34,49 +34,39 @@
 **
 ****************************************************************************/
 
-#ifndef PAGECACHE_H
-#define PAGECACHE_H
+#ifndef PAGESELECTOR_H
+#define PAGESELECTOR_H
 
-#include <QImage>
-#include <QThread>
+#include <QWidget>
 
 QT_BEGIN_NAMESPACE
+class QLabel;
+class QLineEdit;
 class QPdfDocument;
+class QPdfPageNavigation;
+class QToolButton;
 QT_END_NAMESPACE
 
-class PageRenderer : public QThread
+class PageSelector : public QWidget
 {
     Q_OBJECT
 
 public:
-    explicit PageRenderer(QObject *parent = nullptr);
+    explicit PageSelector(QWidget *parent = nullptr);
 
-public slots:
-    void setDocument(QPdfDocument *document);
+    void setPageNavigation(QPdfPageNavigation *pageNavigation);
 
-    void requestPage(int page, qreal zoom, Priority priority = QThread::NormalPriority);
-
-signals:
-    void pageReady(int page, qreal zoom, QImage image);
-
-protected:
-    void run() override;
+private slots:
+    void onCurrentPageChanged(int page);
+    void pageNumberEdited();
 
 private:
-    void renderPage(int page, qreal zoom);
-
-private:
-    QPdfDocument *m_document;
-
-    // current request only
-    int m_page;
-    qreal m_zoom;
+    QPdfPageNavigation *m_pageNavigation;
 
-    // performance statistics
-    qreal m_minRenderTime;
-    qreal m_maxRenderTime;
-    qreal m_totalRenderTime;
-    int m_totalPagesRendered;
+    QLineEdit *m_pageNumberEdit;
+    QLabel *m_pageCountLabel;
+    QToolButton *m_previousPageButton;
+    QToolButton *m_nextPageButton;
 };
 
-#endif // PAGECACHE_H
+#endif // PAGESELECTOR_H
diff --git a/examples/pdf/pdfviewer/pdfviewer.pro b/examples/pdf/pdfviewer/pdfviewer.pro
index 10cacce..d3e7688 100644
--- a/examples/pdf/pdfviewer/pdfviewer.pro
+++ b/examples/pdf/pdfviewer/pdfviewer.pro
@@ -1,21 +1,23 @@
-QT       += core gui widgets pdf
-TARGET = pdfviewer
 TEMPLATE = app
+TARGET = pdfviewer
+QT += core gui widgets pdfwidgets
 
-SOURCES += main.cpp\
-        mainwindow.cpp \
-    sequentialpagewidget.cpp \
-    pagerenderer.cpp
+SOURCES += \
+    main.cpp \
+    mainwindow.cpp \
+    pageselector.cpp \
+    zoomselector.cpp
 
-HEADERS  += mainwindow.h \
-    sequentialpagewidget.h \
-    pagerenderer.h
+HEADERS += \
+    mainwindow.h \
+    pageselector.h \
+    zoomselector.h
 
-FORMS    += mainwindow.ui
+FORMS += \
+    mainwindow.ui
 
 RESOURCES += \
     resources.qrc
 
 target.path = $$[QT_INSTALL_EXAMPLES]/pdf/pdfviewer
 INSTALLS += target
-
diff --git a/examples/pdf/pdfviewer/sequentialpagewidget.cpp b/examples/pdf/pdfviewer/sequentialpagewidget.cpp
deleted file mode 100644
index 904bc17..0000000
--- a/examples/pdf/pdfviewer/sequentialpagewidget.cpp
+++ /dev/null
@@ -1,192 +0,0 @@
-/****************************************************************************
-**
-** Copyright (C) 2016 The Qt Company Ltd.
-** Contact: http://www.qt.io/licensing/
-**
-** This file is part of the QtPDF module of the Qt Toolkit.
-**
-** $QT_BEGIN_LICENSE:LGPL3$
-** 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 http://www.qt.io/terms-conditions. For further
-** information use the contact form at http://www.qt.io/contact-us.
-**
-** GNU Lesser General Public License Usage
-** Alternatively, this file may be used under the terms of the GNU Lesser
-** General Public License version 3 as published by the Free Software
-** Foundation and appearing in the file LICENSE.LGPLv3 included in the
-** packaging of this file. Please review the following information to
-** ensure the GNU Lesser General Public License version 3 requirements
-** will be met: https://www.gnu.org/licenses/lgpl.html.
-**
-** GNU General Public License Usage
-** 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
-** Software Foundation and appearing in the file LICENSE.GPL included in
-** the packaging of this file. Please review the following information to
-** ensure the GNU General Public License version 2.0 requirements will be
-** met: http://www.gnu.org/licenses/gpl-2.0.html.
-**
-** $QT_END_LICENSE$
-**
-****************************************************************************/
-
-#include "sequentialpagewidget.h"
-#include "pagerenderer.h"
-#include <QPaintEvent>
-#include <QPainter>
-#include <QPdfDocument>
-#include <QGuiApplication>
-#include <QScreen>
-#include <QLoggingCategory>
-#include <QElapsedTimer>
-
-Q_DECLARE_LOGGING_CATEGORY(lcExample)
-
-SequentialPageWidget::SequentialPageWidget(QWidget *parent)
-    : QWidget(parent)
-    , m_pageCacheLimit(20)
-    , m_pageRenderer(new PageRenderer())
-    , m_background(Qt::darkGray)
-    , m_placeholderIcon(":icons/images/busy.png")
-    , m_placeholderBackground(Qt::white)
-    , m_pageSpacing(3)
-    , m_topPageShowing(0)
-    , m_zoom(1.)
-    , m_screenResolution(QGuiApplication::primaryScreen()->logicalDotsPerInch() / 72.0)
-    , m_document(nullptr)
-{
-    connect(m_pageRenderer, SIGNAL(pageReady(int, qreal, QImage)), this, SLOT(pageLoaded(int, qreal, QImage)), Qt::QueuedConnection);
-    grabGesture(Qt::SwipeGesture);
-}
-
-SequentialPageWidget::~SequentialPageWidget()
-{
-    delete m_pageRenderer;
-}
-
-void SequentialPageWidget::setDocument(QPdfDocument *document)
-{
-    m_pageRenderer->setDocument(document);
-
-    m_document = document;
-    connect(m_document, &QPdfDocument::statusChanged, this, &SequentialPageWidget::documentStatusChanged);
-
-    documentStatusChanged();
-}
-
-void SequentialPageWidget::setZoom(qreal factor)
-{
-    m_zoom = factor;
-    emit zoomChanged(factor);
-    invalidate();
-}
-
-QSizeF SequentialPageWidget::pageSize(int page)
-{
-//    if (!m_pageSizes.length() <= page)
-//        return QSizeF();
-    return m_pageSizes[page] * m_screenResolution * m_zoom;
-}
-
-void SequentialPageWidget::invalidate()
-{
-    QSizeF totalSize(0, m_pageSpacing);
-    for (int page = 0; page < pageCount(); ++page) {
-        QSizeF size = pageSize(page);
-        totalSize.setHeight(totalSize.height() + size.height());
-        if (size.width() > totalSize.width())
-            totalSize.setWidth(size.width());
-    }
-    m_totalSize = totalSize.toSize();
-    setMinimumSize(m_totalSize);
-    emit zoomChanged(m_zoom);
-    qCDebug(lcExample) << "total size" << m_totalSize;
-    m_pageCache.clear();
-    update();
-}
-
-void SequentialPageWidget::documentStatusChanged()
-{
-    m_pageSizes.clear();
-    m_topPageShowing = 0;
-
-    if (m_document->status() == QPdfDocument::Ready) {
-        for (int page = 0; page < m_document->pageCount(); ++page)
-            m_pageSizes.append(m_document->pageSize(page));
-    }
-
-    invalidate();
-}
-
-void SequentialPageWidget::pageLoaded(int page, qreal zoom, QImage image)
-{
-    Q_UNUSED(zoom)
-    if (m_cachedPagesLRU.length() > m_pageCacheLimit)
-        m_pageCache.remove(m_cachedPagesLRU.takeFirst());
-    m_pageCache.insert(page, image);
-    m_cachedPagesLRU.append(page);
-    update();
-}
-
-int SequentialPageWidget::pageCount()
-{
-    return m_pageSizes.count();
-}
-
-void SequentialPageWidget::paintEvent(QPaintEvent * event)
-{
-    QPainter painter(this);
-    painter.fillRect(event->rect(), m_background);
-
-    if (m_pageSizes.isEmpty())
-        return;
-
-    // Find the first page that needs to be rendered
-    int page = 0;
-    int y = 0;
-    while (page < pageCount()) {
-        QSizeF size = pageSize(page);
-        int height = size.toSize().height();
-        if (y + height >= event->rect().top())
-            break;
-        y += height + m_pageSpacing;
-        ++page;
-    }
-    y += m_pageSpacing;
-    m_topPageShowing = page;
-
-    // Actually render pages
-    while (y < event->rect().bottom() && page < pageCount()) {
-        QSizeF size = pageSize(page);
-        if (m_pageCache.contains(page)) {
-            const QImage &img = m_pageCache[page];
-            painter.fillRect((width() - img.width()) / 2, y, size.width(), size.height(), Qt::white);
-            painter.drawImage((width() - img.width()) / 2, y, img);
-        } else {
-            painter.fillRect((width() - size.width()) / 2, y, size.width(), size.height(), m_placeholderBackground);
-            painter.drawPixmap((size.width() - m_placeholderIcon.width()) / 2,
-                               (size.height() - m_placeholderIcon.height()) / 2, m_placeholderIcon);
-            m_pageRenderer->requestPage(page, m_screenResolution * m_zoom);
-        }
-        y += size.height() + m_pageSpacing;
-        ++page;
-    }
-    m_bottomPageShowing = page - 1;
-    emit showingPageRange(m_topPageShowing, m_bottomPageShowing);
-}
-
-qreal SequentialPageWidget::yForPage(int endPage)
-{
-    // TODO maybe put this loop into a page iterator class
-    int y = m_pageSpacing;
-    for (int page = 0; page < pageCount() && page < endPage; ++page) {
-        QSizeF size = pageSize(page);
-        int height = size.toSize().height();
-        y += height + m_pageSpacing;
-    }
-    return y;
-}
diff --git a/examples/pdf/pdfviewer/zoomselector.cpp b/examples/pdf/pdfviewer/zoomselector.cpp
new file mode 100644
index 0000000..0205489
--- /dev/null
+++ b/examples/pdf/pdfviewer/zoomselector.cpp
@@ -0,0 +1,97 @@
+/****************************************************************************
+**
+** Copyright (C) 2017 Klaralvdalens Datakonsult AB (KDAB).
+** Contact: http://www.qt.io/licensing/
+**
+** This file is part of the QtPDF module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL3$
+** 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 http://www.qt.io/terms-conditions. For further
+** information use the contact form at http://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPLv3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl.html.
+**
+** GNU General Public License Usage
+** 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
+** Software Foundation and appearing in the file LICENSE.GPL included in
+** the packaging of this file. Please review the following information to
+** ensure the GNU General Public License version 2.0 requirements will be
+** met: http://www.gnu.org/licenses/gpl-2.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "zoomselector.h"
+
+#include <QLineEdit>
+
+ZoomSelector::ZoomSelector(QWidget *parent)
+    : QComboBox(parent)
+{
+    setEditable(true);
+
+    addItem(QLatin1String("Fit Width"));
+    addItem(QLatin1String("Fit Page"));
+    addItem(QLatin1String("12%"));
+    addItem(QLatin1String("25%"));
+    addItem(QLatin1String("33%"));
+    addItem(QLatin1String("50%"));
+    addItem(QLatin1String("66%"));
+    addItem(QLatin1String("75%"));
+    addItem(QLatin1String("100%"));
+    addItem(QLatin1String("125%"));
+    addItem(QLatin1String("150%"));
+    addItem(QLatin1String("200%"));
+    addItem(QLatin1String("400%"));
+
+    connect(this, static_cast<void(QComboBox::*)(const QString &)>(&QComboBox::currentIndexChanged),
+            this, &ZoomSelector::onCurrentTextChanged);
+
+    connect(lineEdit(), &QLineEdit::editingFinished,
+            this, [this](){onCurrentTextChanged(lineEdit()->text()); });
+}
+
+void ZoomSelector::setZoomFactor(qreal zoomFactor)
+{
+    setCurrentText(QString::number(qRound(zoomFactor * 100)) + QLatin1String("%"));
+}
+
+void ZoomSelector::reset()
+{
+    setCurrentIndex(8); // 100%
+}
+
+void ZoomSelector::onCurrentTextChanged(const QString &text)
+{
+    if (text == QLatin1String("Fit Width")) {
+        emit zoomModeChanged(QPdfView::FitToWidth);
+    } else if (text == QLatin1String("Fit Page")) {
+        emit zoomModeChanged(QPdfView::FitInView);
+    } else {
+        qreal factor = 1.0;
+
+        QString withoutPercent(text);
+        withoutPercent.remove(QLatin1Char('%'));
+
+        bool ok = false;
+        const int zoomLevel = withoutPercent.toInt(&ok);
+        if (ok)
+            factor = zoomLevel / 100.0;
+
+        emit zoomModeChanged(QPdfView::CustomZoom);
+        emit zoomFactorChanged(factor);
+    }
+}
diff --git a/examples/pdf/pdfviewer/sequentialpagewidget.h b/examples/pdf/pdfviewer/zoomselector.h
index a84a37b..c58d099 100644
--- a/examples/pdf/pdfviewer/sequentialpagewidget.h
+++ b/examples/pdf/pdfviewer/zoomselector.h
@@ -1,6 +1,6 @@
 /****************************************************************************
 **
-** Copyright (C) 2016 The Qt Company Ltd.
+** Copyright (C) 2017 Klaralvdalens Datakonsult AB (KDAB).
 ** Contact: http://www.qt.io/licensing/
 **
 ** This file is part of the QtPDF module of the Qt Toolkit.
@@ -34,66 +34,30 @@
 **
 ****************************************************************************/
 
-#ifndef SEQUENTIALPAGEWIDGET_H
-#define SEQUENTIALPAGEWIDGET_H
+#ifndef ZOOMSELECTOR_H
+#define ZOOMSELECTOR_H
 
-#include <QWidget>
+#include <QComboBox>
+#include <QPdfView>
 
-QT_BEGIN_NAMESPACE
-class QPdfDocument;
-QT_END_NAMESPACE
-
-class PageRenderer;
-
-class SequentialPageWidget : public QWidget
+class ZoomSelector : public QComboBox
 {
     Q_OBJECT
-public:
-    explicit SequentialPageWidget(QWidget *parent = 0);
-    ~SequentialPageWidget();
 
-    void paintEvent(QPaintEvent * event);
-    qreal zoom() { return m_zoom; }
-    qreal yForPage(int page);
-    int topPageShowing() { return m_topPageShowing; }
-    int bottomPageShowing() { return m_bottomPageShowing; }
-
-    void setDocument(QPdfDocument *document);
+public:
+    explicit ZoomSelector(QWidget *parent = nullptr);
 
 public slots:
-    void setZoom(qreal factor);
-    void invalidate();
+    void setZoomFactor(qreal zoomFactor);
+
+    void reset();
 
 signals:
-    void showingPageRange(int start, int end);
-    void zoomChanged(qreal factor);
+    void zoomModeChanged(QPdfView::ZoomMode zoomMode);
+    void zoomFactorChanged(qreal zoomFactor);
 
 private slots:
-    void documentStatusChanged();
-    void pageLoaded(int page, qreal zoom, QImage image);
-
-private:
-    int pageCount();
-    QSizeF pageSize(int page);
-    void render(int page);
-
-private:
-    QHash<int, QImage> m_pageCache;
-    QVector<int> m_cachedPagesLRU;
-    int m_pageCacheLimit;
-    QVector<QSizeF> m_pageSizes;
-    PageRenderer *m_pageRenderer;
-    QBrush m_background;
-    QPixmap m_placeholderIcon;
-    QBrush m_placeholderBackground;
-    int m_pageSpacing;
-    int m_topPageShowing;
-    int m_bottomPageShowing;
-    QSize m_totalSize;
-    qreal m_zoom;
-    qreal m_screenResolution; // pixels per point
-
-    QPdfDocument *m_document;
+    void onCurrentTextChanged(const QString &text);
 };
 
-#endif // SEQUENTIALPAGEWIDGET_H
+#endif // ZOOMSELECTOR_H