1*aaef562fSAndrew Rist /************************************************************** 2cdf0e10cSrcweir * 3*aaef562fSAndrew Rist * Licensed to the Apache Software Foundation (ASF) under one 4*aaef562fSAndrew Rist * or more contributor license agreements. See the NOTICE file 5*aaef562fSAndrew Rist * distributed with this work for additional information 6*aaef562fSAndrew Rist * regarding copyright ownership. The ASF licenses this file 7*aaef562fSAndrew Rist * to you under the Apache License, Version 2.0 (the 8*aaef562fSAndrew Rist * "License"); you may not use this file except in compliance 9*aaef562fSAndrew Rist * with the License. You may obtain a copy of the License at 10*aaef562fSAndrew Rist * 11*aaef562fSAndrew Rist * http://www.apache.org/licenses/LICENSE-2.0 12*aaef562fSAndrew Rist * 13*aaef562fSAndrew Rist * Unless required by applicable law or agreed to in writing, 14*aaef562fSAndrew Rist * software distributed under the License is distributed on an 15*aaef562fSAndrew Rist * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 16*aaef562fSAndrew Rist * KIND, either express or implied. See the License for the 17*aaef562fSAndrew Rist * specific language governing permissions and limitations 18*aaef562fSAndrew Rist * under the License. 19*aaef562fSAndrew Rist * 20*aaef562fSAndrew Rist *************************************************************/ 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