sd/source/ui/slidesorter/inc/cache/SlsCacheContext.hxx

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  19
  20 #ifndef INCLUDED_SD_SOURCE_UI_SLIDESORTER_INC_CACHE_SLSCACHECONTEXT_HXX
  21 #define INCLUDED_SD_SOURCE_UI_SLIDESORTER_INC_CACHE_SLSCACHECONTEXT_HXX
  22
  23 #include <sal/types.h>
  24 #include <com/sun/star/uno/XInterface.hpp>
  25 #include <boost/shared_ptr.hpp>
  26 #include <vector>
  27
  28 class SdrPage;
  29 class Bitmap;
  30
  31 namespace sd { namespace slidesorter { namespace cache {
  32
  33 typedef const SdrPage* CacheKey;
  34
  35 /** This interface allows the individualisation of different instances of
  36     the PreviewCache.
  37 */
  38 class CacheContext
  39 {
  40 public:
  41     virtual ~CacheContext() {}
  42
  43     /** This method is called when the asynchronous creation of a preview
  44         has been finished.
  45         @param aKey
  46             The key of the page for which the preview has been created.
  47         @param aPreview
  48             The newly created preview.
  49     */
  50     virtual void NotifyPreviewCreation (
  51         CacheKey aKey,
  52         const Bitmap& rPreview) = 0;
  53
  54     /** Called to determine whether the system is idle and a preview can be
  55         created without annoying the user.
  56     */
  57     virtual bool IsIdle() = 0;
  58
  59     /** This method is used to determine whether a page is currently visible
  60         or not.  It is called when the cache becomes to large and some
  61         previews have to be released or scaled down.
  62     */
  63     virtual bool IsVisible (CacheKey aKey) = 0;
  64
  65     /** Return the page associdated with the given key.  Note that different
  66         keys may map to a single page (this may be the case with custom
  67         slide shows.)
  68     */
  69     virtual const SdrPage* GetPage (CacheKey aKey) = 0;
  70
  71     /** This method is used when the request queue is filled.  It asks for
  72         the list of visible entries and maybe for the list of not visible
  73         entries and creates preview creation requests for them.
  74         @param bVisible
  75             When this is <FALSE/> then the implementation can decide whether
  76             to allow rendering of previews that are not visible (ahead of
  77             time). When not then return an empty pointer or an empty vector.
  78     */
  79     virtual ::boost::shared_ptr<std::vector<CacheKey> > GetEntryList (bool bVisible) = 0;
  80
  81     /** Return the priority that defines the order in which previews are
  82         created for different keys/pages.  Typically the visible pages come
  83         first, then top-down, left-to-right.
  84     */
  85     virtual sal_Int32 GetPriority (CacheKey aKey) = 0;
  86
  87     /** Return the model to which the pages belong for which the called
  88         cache manages the previews.  Different caches that belong to the
  89         same model but have different preview sizes may access previews of
  90         each other in order to create fast previews of the previews.
  91     */
  92     virtual ::com::sun::star::uno::Reference<com::sun::star::uno::XInterface> GetModel() = 0;
  93 };
  94
  95 typedef ::boost::shared_ptr<CacheContext> SharedCacheContext;
  96
  97 } } } // end of namespace ::sd::slidesorter::cache
  98
  99 #endif
 100
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