1 /************************************************************** 2 * 3 * Licensed to the Apache Software Foundation (ASF) under one 4 * or more contributor license agreements. See the NOTICE file 5 * distributed with this work for additional information 6 * regarding copyright ownership. The ASF licenses this file 7 * to you under the Apache License, Version 2.0 (the 8 * "License"); you may not use this file except in compliance 9 * with the License. You may obtain a copy of the License at 10 * 11 * http://www.apache.org/licenses/LICENSE-2.0 12 * 13 * Unless required by applicable law or agreed to in writing, 14 * software distributed under the License is distributed on an 15 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 16 * KIND, either express or implied. See the License for the 17 * specific language governing permissions and limitations 18 * under the License. 19 * 20 *************************************************************/ 21 22 23 24 #ifndef INCLUDED_SLIDESHOW_ACTIVITY_HXX 25 #define INCLUDED_SLIDESHOW_ACTIVITY_HXX 26 27 #include <sal/types.h> 28 29 #include <boost/shared_ptr.hpp> 30 31 #include "disposable.hxx" 32 33 34 /* Definition of Activity interface */ 35 36 namespace slideshow 37 { 38 namespace internal 39 { 40 41 class Activity : public Disposable 42 { 43 public: 44 /** Perform the activity associated with this interface's 45 implementation. 46 47 @return true, if activity continues, or false, if activity has 48 ended. 49 */ 50 virtual bool perform() = 0; 51 52 /** Calculates whether the activity lags time. 53 54 If this method returns a time lag greater than 0.0, 55 the ActivitiesQueue will adjust the global slideshow 56 time, by subtracting the given amount of lag. 57 58 @return time lag or 0.0. Value must be greater or 59 equal than zero. 60 */ 61 virtual double calcTimeLag() const = 0; 62 63 /** Query whether this activity is still continuing 64 65 @return true, if this activity still 66 continues. Returns false, if activity has ended. It is 67 required that operator() returns false, when 68 isActive() returns false. Furthermore, it is required 69 that the inactive state is persistent; an activity 70 that has become inactive (i.e. isActive() once 71 returned false) must stay in that state eternally. 72 */ 73 virtual bool isActive() const = 0; 74 75 /** Notifies the Activity that it has now left the 76 ActivitiesQueue 77 78 Use this method to react on the queue removal 79 event. For animated shapes, this is e.g. used to 80 switch back to the non-sprite presentation mode of the 81 shape. 82 */ 83 virtual void dequeued() = 0; 84 85 /** Forces this activity deactivate and get to its end state 86 (if possible), but does _not_ dispose. 87 */ 88 virtual void end() = 0; 89 }; 90 91 typedef ::boost::shared_ptr< Activity > ActivitySharedPtr; 92 93 } 94 } 95 96 #endif /* INCLUDED_SLIDESHOW_ACTIVITY_HXX */ 97