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2cdf0e10cSrcweir  *
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21*aaef562fSAndrew Rist 
22*aaef562fSAndrew Rist 
23cdf0e10cSrcweir 
24cdf0e10cSrcweir #ifndef INCLUDED_SLIDESHOW_VIEWUPDATE_HXX
25cdf0e10cSrcweir #define INCLUDED_SLIDESHOW_VIEWUPDATE_HXX
26cdf0e10cSrcweir 
27cdf0e10cSrcweir #include "disposable.hxx"
28cdf0e10cSrcweir #include "view.hxx"
29cdf0e10cSrcweir #include <boost/shared_ptr.hpp>
30cdf0e10cSrcweir 
31cdf0e10cSrcweir /* Definition of ViewUpdate interface */
32cdf0e10cSrcweir 
33cdf0e10cSrcweir namespace slideshow
34cdf0e10cSrcweir {
35cdf0e10cSrcweir     namespace internal
36cdf0e10cSrcweir     {
37cdf0e10cSrcweir         /** Interface for something that can perform view updates.
38cdf0e10cSrcweir 
39cdf0e10cSrcweir             Use this interface for objects that perform view updates
40cdf0e10cSrcweir             from time to time, e.g. slide content. Availability of
41cdf0e10cSrcweir             updates can be queried, and subsequently performed.
42cdf0e10cSrcweir          */
43cdf0e10cSrcweir         class ViewUpdate : public Disposable
44cdf0e10cSrcweir         {
45cdf0e10cSrcweir         public:
46cdf0e10cSrcweir             /** Perform the update action on all views
47cdf0e10cSrcweir 
48cdf0e10cSrcweir                 @return true, if the update was performed
49cdf0e10cSrcweir                 successfully, false otherwise.
50cdf0e10cSrcweir              */
51cdf0e10cSrcweir             virtual bool update() = 0;
52cdf0e10cSrcweir 
53cdf0e10cSrcweir             /** Perform the update action on given view only
54cdf0e10cSrcweir 
55cdf0e10cSrcweir                 @return true, if the update was performed
56cdf0e10cSrcweir                 successfully, false otherwise.
57cdf0e10cSrcweir              */
58cdf0e10cSrcweir             virtual bool update( ViewSharedPtr const& rView ) = 0;
59cdf0e10cSrcweir 
60cdf0e10cSrcweir             /** Query whether updates are pending
61cdf0e10cSrcweir 
62cdf0e10cSrcweir                 @return true, if updates are pending. Calling update()
63cdf0e10cSrcweir                 subsequently will perform the pending update then.
64cdf0e10cSrcweir              */
65cdf0e10cSrcweir             virtual bool needsUpdate() const = 0;
66cdf0e10cSrcweir         };
67cdf0e10cSrcweir 
68cdf0e10cSrcweir         typedef ::boost::shared_ptr< ViewUpdate > ViewUpdateSharedPtr;
69cdf0e10cSrcweir     }
70cdf0e10cSrcweir }
71cdf0e10cSrcweir 
72cdf0e10cSrcweir #endif /* INCLUDED_SLIDESHOW_VIEWUPDATE_HXX */
73