sd/source/ui/slidesorter/cache/SlsCacheCompactor.hxx

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  30
  31 #ifndef SD_SLIDESORTER_CACHE_COMPACTOR_HXX
  32 #define SD_SLIDESORTER_CACHE_COMPACTOR_HXX
  33
  34 #include <sal/types.h>
  35 #include <vcl/timer.hxx>
  36 #include <memory>
  37
  38 namespace sd { namespace slidesorter { namespace cache {
  39
  40 class BitmapCache;
  41 class BitmapCompressor;
  42
  43 /** This is an interface class whose implementations are created via the
  44     Create() factory method.
  45 */
  46 class CacheCompactor
  47 {
  48 public:
  49     virtual ~CacheCompactor (void) {};
  50
  51     /** Create a new instance of the CacheCompactor interface class.  The
  52         type of compaction algorithm used depends on values from the
  53         configuration: the SlideSorter/PreviewCache/CompactionPolicy
  54         property of the Impress.xcs file currently supports the values
  55         "None" and "Compress".  With the later the CompressionPolicy
  56         property is evaluated which implementation of the BitmapCompress
  57         interface class to use as bitmap compressor.
  58         @param rCache
  59             The bitmap cache on which to operate.
  60         @param nMaximalCacheSize
  61             The total number of bytes the off-screen bitmaps in the cache
  62             may have.  When the Run() method is (indirectly) called the
  63             compactor tries to reduce that summed size of off-screen bitmaps
  64             under this number.  However, it is not guaranteed that this
  65             works in all cases.
  66     */
  67     static ::std::auto_ptr<CacheCompactor> Create (
  68         BitmapCache& rCache,
  69         sal_Int32 nMaximalCacheSize);
  70
  71     /** Request a compaction of the off-screen previews in the bitmap
  72         cache.  This calls via a timer the Run() method.
  73     */
  74     virtual void RequestCompaction (void);
  75
  76 protected:
  77     BitmapCache& mrCache;
  78     sal_Int32 mnMaximalCacheSize;
  79
  80     CacheCompactor(
  81         BitmapCache& rCache,
  82         sal_Int32 nMaximalCacheSize);
  83
  84     /** This method actually tries to reduce the total number of bytes used
  85         by the off-screen preview bitmaps.
  86     */
  87     virtual void Run (void) = 0;
  88
  89 private:
  90     /** This timer is used to collect calles to RequestCompaction() and
  91         eventually call Run().
  92     */
  93     Timer maCompactionTimer;
  94     bool mbIsCompactionRunning;
  95     DECL_LINK(CompactionCallback, Timer*);
  96 };
  97
  98
  99
 100
 101 } } } // end of namespace ::sd::slidesorter::cache
 102
 103 #endif