pdfviewer example: stop creating placeholder images in PageCache

4 files changed, 14 insertions, 18 deletions

diff --git a/examples/widgets/pdfviewer/pagecache.cpp b/examples/widgets/pdfviewer/pagecache.cpp
index 589a7b0..293b2d4 100644
--- a/examples/widgets/pdfviewer/pagecache.cpp
+++ b/examples/widgets/pdfviewer/pagecache.cpp
@@ -10,8 +10,6 @@ PageCache::PageCache(QPdfDocument *doc, qreal zoom)
     : QThread(Q_NULLPTR)
     , m_doc(doc)
     , m_zoom(zoom)
-    , m_placeholderIcon(":icons/images/busy.png")
-    , m_placeholderBackground(Qt::white)
     , m_minRenderTime(1000000000.)
     , m_maxRenderTime(0.)
     , m_totalRenderTime(0.)
@@ -25,7 +23,7 @@ PageCache::~PageCache()
 
 /*!
    Get the result from the cache,
-   or a placeholder pixmap if unavailable.
+   or an invalid pixmap if unavailable.
  */
 QPixmap PageCache::get(int page)
 {
@@ -34,18 +32,7 @@ QPixmap PageCache::get(int page)
         return m_pageCache[page];
     if (!isRunning())
         start(QThread::LowestPriority);
-    QSizeF sizeF = m_doc->pageSize(page);
-    if (!sizeF.isValid())
-        return QPixmap();
-    QSize size = QSizeF(sizeF * m_zoom).toSize();
-    QPixmap placeholder(size);
-    {
-        QPainter painter(&placeholder);
-        painter.fillRect(QRect(QPoint(), size), m_placeholderBackground);
-        painter.drawPixmap((size.width() - m_placeholderIcon.width()) / 2,
-            (size.height() - m_placeholderIcon.height()) / 2, m_placeholderIcon);
-    }
-    return placeholder;
+    return QPixmap();
 }
 
 void PageCache::run()
diff --git a/examples/widgets/pdfviewer/pagecache.h b/examples/widgets/pdfviewer/pagecache.h
index b1a1a93..b2c063f 100644
--- a/examples/widgets/pdfviewer/pagecache.h
+++ b/examples/widgets/pdfviewer/pagecache.h
@@ -32,8 +32,6 @@ private:
     QHash<int, QPixmap> m_pageCache;
     qreal m_zoom;
     int m_lastPageRequested;
-    QPixmap m_placeholderIcon;
-    QBrush m_placeholderBackground;
 
     // performance statistics
     qreal m_minRenderTime;
diff --git a/examples/widgets/pdfviewer/sequentialpagewidget.cpp b/examples/widgets/pdfviewer/sequentialpagewidget.cpp
index 6b84015..da880be 100644
--- a/examples/widgets/pdfviewer/sequentialpagewidget.cpp
+++ b/examples/widgets/pdfviewer/sequentialpagewidget.cpp
@@ -16,6 +16,8 @@ SequentialPageWidget::SequentialPageWidget(QWidget *parent)
     , m_pageCache(Q_NULLPTR)
     , m_background(Qt::darkGray)
     , m_pageSpacing(3)
+    , m_placeholderIcon(":icons/images/busy.png")
+    , m_placeholderBackground(Qt::white)
     , m_topPageShowing(0)
     , m_zoom(1.)
     , m_screenResolution(QGuiApplication::primaryScreen()->logicalDotsPerInch() / 72.0)
@@ -99,7 +101,14 @@ void SequentialPageWidget::paintEvent(QPaintEvent * event)
     // Actually render pages
     while (y < event->rect().bottom() && page < m_doc->pageCount()) {
         const QPixmap &pm = m_pageCache->get(page);
-        painter.drawPixmap((width() - pm.width()) / 2, y, pm);
+        if (pm.isNull()) {
+            QSizeF size = pageSize(page);
+            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);
+        } else {
+            painter.drawPixmap((width() - pm.width()) / 2, y, pm);
+        }
         y += pm.height() + m_pageSpacing;
         ++page;
     }
diff --git a/examples/widgets/pdfviewer/sequentialpagewidget.h b/examples/widgets/pdfviewer/sequentialpagewidget.h
index 23dfe7f..3d2c70d 100644
--- a/examples/widgets/pdfviewer/sequentialpagewidget.h
+++ b/examples/widgets/pdfviewer/sequentialpagewidget.h
@@ -36,6 +36,8 @@ private:
     QPdfDocument *m_doc;
     PageCache *m_pageCache;
     QBrush m_background;
+    QPixmap m_placeholderIcon;
+    QBrush m_placeholderBackground;
     int m_pageSpacing;
     int m_topPageShowing;
     int m_bottomPageShowing;