videocollection/videocollectionwrapper/inc/videothumbnaildata.h
changeset 30 4f111d64a341
child 34 bbb98528c666
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/videocollection/videocollectionwrapper/inc/videothumbnaildata.h	Thu Apr 01 22:38:49 2010 +0300
@@ -0,0 +1,161 @@
+/*
+* Copyright (c) 2009 Nokia Corporation and/or its subsidiary(-ies).
+* All rights reserved.
+* This component and the accompanying materials are made available
+* under the terms of "Eclipse Public License v1.0"
+* which accompanies this distribution, and is available
+* at the URL "http://www.eclipse.org/legal/epl-v10.html".
+*
+* Initial Contributors:
+* Nokia Corporation - initial contribution.
+*
+* Contributors:
+*
+* Description:   VideoThumbnailData singleton class definition
+*/
+
+#ifndef __VIDEOTHUMBNAILDATA_H__
+#define __VIDEOTHUMBNAILDATA_H__
+
+// INCLUDES
+#include <QObject>
+#include <QHash>
+#include <QPair>
+#include <QIcon>
+#include <QSet>
+#include <QPointer>
+#include <mpxitemid.h>
+
+#include "videocollectionexport.h"
+
+// FORWARD DECLARATIONS
+class VideoThumbnailDataPrivate;
+
+// CLASS DECLARATIONS
+
+class VIDEOCOLLECTION_DLL_EXPORT VideoThumbnailData : public QObject
+{
+    /**
+     * Defined to be able to use signals and slots.
+     */
+    Q_OBJECT
+
+    /**
+     * disable copy-constructor and assignment operator
+     */
+	Q_DISABLE_COPY(VideoThumbnailData)
+
+public:
+
+    /*
+     * Thumbnail fetch priorities.
+     */
+    enum VideoThumbnailPriority
+    {
+        VideoThumbnailPriorityLow = 2000,
+        VideoThumbnailPriorityMedium = 3000,
+        VideoThumbnailPriorityHigh = 5000
+    };    
+    
+    /**
+     * Returns singleton instance for this class.
+     *
+     * @return The singleton instance.
+     *
+     */
+    static VideoThumbnailData &instance();
+
+    /**
+     * Method starts fetching thumbnail for the video specified by given mediaId
+     * Media IDs are used as a key identification in the thumbnail map where data is
+     * collected. Id is passed to thumbnail manager as internal data and when
+     * thumbnail is fetched and thumbnailReadySlot is signaled, id is used to notify
+     * client about which item's thumbnail is ready.
+     *
+     * If thumbnail fetching is started succesfully, method saves thumbnail item
+     * into local repository with default thumbnail data.
+     *
+     * @param mediaId media id for which to start fetching thumbnail
+     * @param priority priority for the fetch
+     *
+     * @return int: thumbnail id or -1 if fetch starting fails.
+     *
+     */
+    int startFetchingThumbnail(int mediaId, int priority);
+    
+    /**
+     * Method removes thumbnail data from the local repository.
+     *
+     * @param mediaId id for media whose thumbnail is to be removed
+     *
+     * @return bool: true if item removed correctly, false if not.
+     *
+     */
+    bool removeThumbnail(TMPXItemId mediaId);
+    
+    /**
+     * Method returns a pointer to video's thumbnail.
+     *
+     * If thumbnail fetching is ongoing or not yet started, pointer to default 
+     * thumbnail is returned.
+     *
+     * @param mediaId media id for which to get thumbnail
+     * @param tnData reference to thumbnail data where data is occupied
+     *
+     * @return QIcon* thumbnail pointer
+     *
+     */
+    const QIcon* getThumbnail(TMPXItemId mediaId);
+
+    /**
+     * Starts background thumbnail fetching.
+     *
+     * @param fetchIndex index where to start the background thumbnail fetching.
+     *  
+     */
+    void startBackgroundFetching(int fetchIndex);
+    
+    /**
+     * Enables or disables thumbnail background fetching. Default is enabled.
+     * 
+     * @param enable true enables and false disables thumbnail background fetching.
+     */
+    void enableBackgroundFetching(bool enable);
+    
+    /**
+     * Frees allocated data for thumbnails and cancels ongoing fetches.
+     * 
+     */
+    void freeThumbnailData();
+
+signals:
+
+    /**
+     * This signal is emitted from thumbnailReadySlot, when
+     *
+     * @param mediaIds: media ids of the videos whose thumbnail is ready.
+     *
+     */
+    void thumbnailsFetched(QList<TMPXItemId> mediaIds);
+    
+private:
+
+    /**
+     * Default constructor
+     */
+    VideoThumbnailData();
+
+    /**
+     * Destructor
+     */
+    ~VideoThumbnailData();
+    
+    /**
+     * Private implementation.
+     */
+    QPointer<VideoThumbnailDataPrivate> const d_ptr;
+};
+
+#endif  // __VIDEOTHUMBNAILDATA_H__
+
+// End of file