From fa3f297b064a2ca904cea50103cc5d09f37cf9f2 Mon Sep 17 00:00:00 2001
From: Pino Toscano <pino@kde.org>
Date: Thu, 4 Jan 2007 00:02:48 +0000
Subject: [PATCH] Fix a nasty bug that could happened in presentation mode:
 when requestng -synchronously- a pixmap for the current page, it could be
 scheduled in the queue. Then, requesting the previous and next page in
 presentation mode -in a second request- caused the deletion of the original
 page request The fix consists in requesting all the requests -at once-, so no
 request is lost. Furthermore, swap the order of previous and next page
 request so the next page pixmap is requested before (worth touching Document
 directly?)

svn path=/trunk/playground/graphics/okular/; revision=619673
---
 ui/presentationwidget.cpp | 26 ++++++++++++--------------
 1 file changed, 12 insertions(+), 14 deletions(-)

diff --git a/ui/presentationwidget.cpp b/ui/presentationwidget.cpp
index 6bee4a210..9c2f215cd 100644
--- a/ui/presentationwidget.cpp
+++ b/ui/presentationwidget.cpp
@@ -589,32 +589,30 @@ void PresentationWidget::changePage( int newPage )
         // operation will take long: set busy cursor
         QApplication::setOverrideCursor( KCursor::workingCursor() );
         // request the pixmap
-        QLinkedList< Okular::PixmapRequest * > request;
-        request.push_back( new Okular::PixmapRequest( PRESENTATION_ID, m_frameIndex, pixW, pixH, PRESENTATION_PRIO, false ) );
-        m_document->requestPixmaps( request );
+        QLinkedList< Okular::PixmapRequest * > requests;
+        requests.push_back( new Okular::PixmapRequest( PRESENTATION_ID, m_frameIndex, pixW, pixH, PRESENTATION_PRIO, false ) );
         // restore cursor
         QApplication::restoreOverrideCursor();
         // ask for next and previous page if not in low memory usage setting
         if (Okular::Settings::memoryLevel() != Okular::Settings::EnumMemoryLevel::Low && Okular::Settings::enableThreading()) {
-            QLinkedList< Okular::PixmapRequest * > asyncRequests;
-            if (newPage + 1 < (int)m_document->pages())
-            {
-                PresentationFrame *nextFrame = m_frames[ newPage + 1 ];
-                pixW = nextFrame->geometry.width();
-                pixH = nextFrame->geometry.height();
-                if ( !nextFrame->page->hasPixmap( PRESENTATION_ID, pixW, pixH ) )
-                    asyncRequests.push_back( new Okular::PixmapRequest( PRESENTATION_ID, newPage + 1, pixW, pixH, PRESENTATION_PRELOAD_PRIO, true ) );
-            }
             if (newPage - 1 >= 0)
             {
                 PresentationFrame *prevFrame = m_frames[ newPage - 1 ];
                 pixW = prevFrame->geometry.width();
                 pixH = prevFrame->geometry.height();
                 if ( !prevFrame->page->hasPixmap( PRESENTATION_ID, pixW, pixH ) )
-                    asyncRequests.push_back( new Okular::PixmapRequest( PRESENTATION_ID, newPage - 1, pixW, pixH, PRESENTATION_PRELOAD_PRIO, true ) );
+                    requests.push_back( new Okular::PixmapRequest( PRESENTATION_ID, newPage - 1, pixW, pixH, PRESENTATION_PRELOAD_PRIO, true ) );
+            }
+            if (newPage + 1 < (int)m_document->pages())
+            {
+                PresentationFrame *nextFrame = m_frames[ newPage + 1 ];
+                pixW = nextFrame->geometry.width();
+                pixH = nextFrame->geometry.height();
+                if ( !nextFrame->page->hasPixmap( PRESENTATION_ID, pixW, pixH ) )
+                    requests.push_back( new Okular::PixmapRequest( PRESENTATION_ID, newPage + 1, pixW, pixH, PRESENTATION_PRELOAD_PRIO, true ) );
             }
-            if (!asyncRequests.isEmpty()) m_document->requestPixmaps( asyncRequests );
         }
+        m_document->requestPixmaps( requests );
     }
     else
     {