| /************************************************************** |
| * |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| * |
| *************************************************************/ |
| |
| |
| |
| #ifndef INCLUDED_SLIDESHOW_EVENTQUEUE_HXX |
| #define INCLUDED_SLIDESHOW_EVENTQUEUE_HXX |
| |
| #include <canvas/elapsedtime.hxx> |
| #include <osl/mutex.hxx> |
| |
| #include "event.hxx" |
| |
| #include <boost/noncopyable.hpp> |
| #include <functional> |
| #include <queue> |
| #include <vector> |
| |
| |
| /* Definition of ActivitiesQueue class */ |
| |
| namespace slideshow |
| { |
| namespace internal |
| { |
| /** This class handles events in a presentation. Events are |
| time instants where e.g. effects start. |
| */ |
| class EventQueue : private ::boost::noncopyable |
| { |
| public: |
| EventQueue( |
| ::boost::shared_ptr< ::canvas::tools::ElapsedTime > |
| const & pPresTimer ); |
| |
| ~EventQueue(); |
| |
| /** Add the given event to the queue. The event is fired |
| at, or shortly after, its Event::getActivationTime instant. |
| */ |
| bool addEvent( const EventSharedPtr& event ); |
| |
| /** Add the given event to the queue. The event is fired |
| at, or shortly after, its Event::getActivationTime instant. |
| The difference to addEvent() is that events added during |
| process() are postponed to next process(). |
| */ |
| bool addEventForNextRound( const EventSharedPtr& event ); |
| |
| /** Another way to control the order of asynchronous event |
| exeqution. Use this method to schedule events that are to |
| be executed after all regular events that have no delay, |
| even when they schedule new regular events without delay. |
| */ |
| bool addEventWhenQueueIsEmpty (const EventSharedPtr& rpEvent); |
| |
| /** Process the event queue. |
| |
| This method executes all events whose timeout has |
| expired when calling this method (i.e. all events |
| whose scheduled time is less or equal the current |
| time). |
| |
| Check for the next available event's timeout via |
| nextTimeout(), or whether the queue is empty |
| altogether via isEmpty(). |
| */ |
| void process(); |
| |
| /** Query state of the queue |
| |
| @return false, if queue is empty, true otherwise |
| */ |
| bool isEmpty() const; |
| |
| /** Query timeout for the topmost event in the queue. |
| |
| @return Timeout in seconds, until the next event is |
| ready. The time returned here is relative to the pres |
| timer (i.e. the timer specified at the EventQueue |
| constructor). When the queue is empty (i.e. isEmpty() |
| returns true), the returned value is the highest |
| representable double value |
| (::std::numeric_limits<double>::max()). If the topmost |
| event in the queue is already pending, the timeout |
| returned here will actually be negative. |
| */ |
| double nextTimeout() const; |
| |
| /** Remove all pending events from the queue. |
| */ |
| void clear(); |
| |
| /** Forces an empty queue, firing all events immediately |
| without minding any times. |
| @attention do only call from event loop, this calls process_()! |
| */ |
| void forceEmpty(); |
| |
| /** Gets the queue's timer object. |
| */ |
| ::boost::shared_ptr< ::canvas::tools::ElapsedTime > const & |
| getTimer() const { return mpTimer; } |
| |
| private: |
| mutable ::osl::Mutex maMutex; |
| |
| struct EventEntry : public ::std::unary_function<EventEntry, bool> |
| { |
| EventSharedPtr pEvent; |
| double nTime; |
| |
| bool operator<( const EventEntry& ) const; // to leverage priority_queue's default compare |
| |
| EventEntry( EventSharedPtr const& p, double t ) |
| : pEvent(p), nTime(t) {} |
| }; |
| |
| typedef ::std::priority_queue< EventEntry > ImplQueueType; |
| ImplQueueType maEvents; |
| typedef ::std::vector<EventEntry> EventEntryVector; |
| EventEntryVector maNextEvents; |
| ImplQueueType maNextNextEvents; |
| void process_( bool bFireAllEvents ); |
| |
| // perform timing of events via relative time |
| // measurements. The world time starts, when the |
| // EventQueue object is created |
| ::boost::shared_ptr< ::canvas::tools::ElapsedTime > mpTimer; |
| }; |
| |
| } |
| } |
| #endif /* INCLUDED_SLIDESHOW_EVENTQUEUE_HXX */ |