[dolphin] Animate gifs on preview

Summary:
Adds the capability to view animated images on the preview in the information panel.
This was a request from a user back in 2009 (https://bugs.kde.org/show_bug.cgi?id=182257), but I think nowadays with stickers/memes and what not, it's even more useful.
It keeps the size default transition of the preview viewer before starting the animation, so that the visual integration is smoother.

{F7289110}

FEATURE: 182257
FIXED-IN: 19.11.80

Test Plan: Open the information panel and hover over some animated images (gif/webp/mng)

Reviewers: #dolphin, #vdg, ngraham, elvisangelaccio

Reviewed By: #vdg, ngraham

Subscribers: pino, fuksitter, meven, broulik, kfm-devel

Tags: #dolphin

Differential Revision: https://phabricator.kde.org/D23538

1 files changed, 9 insertions, 1 deletions

diff --git a/src/panels/information/informationpanelcontent.cpp b/src/panels/information/informationpanelcontent.cpp
index b051603fd..2a8682a12 100644
--- a/src/panels/information/informationpanelcontent.cpp
+++ b/src/panels/information/informationpanelcontent.cpp
@@ -169,6 +169,7 @@ void InformationPanelContent::showItem(const KFileItem& item)
     if (item != m_item) {
         m_item = item;
 
+        m_preview->stopAnimatedImage();
         refreshMetaData();
     }
     refreshPreview();
@@ -237,7 +238,8 @@ void InformationPanelContent::refreshPreview()
             refreshPixmapView();
 
             const QString mimeType = m_item.mimetype();
-            m_isVideo = mimeType.startsWith(QLatin1String("video/"));
+            const bool isAnimatedImage = m_preview->isAnimatedImage(itemUrl.toLocalFile());
+            m_isVideo = !isAnimatedImage && mimeType.startsWith(QLatin1String("video/"));
             usePhonon = m_isVideo || mimeType.startsWith(QLatin1String("audio/"));
 
             if (usePhonon) {
@@ -268,6 +270,9 @@ void InformationPanelContent::refreshPreview()
                     adjustWidgetSizes(parentWidget()->width());
                 }
             } else {
+                if (isAnimatedImage) {
+                    m_preview->setAnimatedImageFileName(itemUrl.toLocalFile());
+                }
                 // When we don't need it, hide the phonon widget first to avoid flickering
                 m_phononWidget->hide();
                 m_preview->show();
@@ -276,6 +281,7 @@ void InformationPanelContent::refreshPreview()
             }
         }
     } else {
+        m_preview->stopAnimatedImage();
         m_preview->hide();
         m_phononWidget->hide();
     }
@@ -303,6 +309,8 @@ void InformationPanelContent::showItems(const KFileItemList& items)
         m_previewJob->kill();
     }
 
+    m_preview->stopAnimatedImage();
+
     m_preview->setPixmap(
         QIcon::fromTheme(QStringLiteral("dialog-information")).pixmap(KIconLoader::SizeEnormous, KIconLoader::SizeEnormous)
     );