vaikene.ee Git - evaf/blob - src/libs/Common/eventqueue.cpp

   1 /**
   2  * @file Common/eventqueue.cpp
   3  * @brief Event queue interface implementation
   4  * @author Enar Vaikene
   5  *
   6  * Copyright (c) 2011 Enar Vaikene
   7  *
   8  * This file is part of the eVaf C++ cross-platform application development framework.
   9  *
  10  * This file can be used under the terms of the GNU General Public License
  11  * version 3.0 as published by the Free Software Foundation and appearing in
  12  * the file LICENSE included in the packaging of this file. Please review the
  13  * the following information to ensure the GNU General Public License version
  14  * 3.0 requirements will be met: http://www.gnu.org/copyleft/gpl.html.
  15  *
  16  * Alternatively, this file may be used in accordance with the Commercial License
  17  * Agreement provided with the Software.
  18  */
  19
  20 #include "eventqueue.h"
  21 #include "event.h"
  22 #include "globals.h"
  23 #include "iregistry.h"
  24 #include "version.h"
  25
  26 #include <QtCore>
  27
  28
  29 //-------------------------------------------------------------------
  30
  31 using namespace eVaf::Common;
  32
  33 iEventQueue * iEventQueue::instance()
  34 {
  35     static Internal::EventQueue singleton;
  36     return &singleton;
  37 }
  38
  39
  40 //-------------------------------------------------------------------
  41
  42 using namespace eVaf::Common::Internal;
  43
  44 EventQueue::EventQueue()
  45     : iEventQueue()
  46     , mNextEventId(1)
  47 {
  48 }
  49
  50 EventQueue::~EventQueue()
  51 {
  52 }
  53
  54 bool EventQueue::event(QEvent * e)
  55 {
  56     // Is it an eVaf event?
  57     if (e->type() == Event::eVafEvent) {
  58
  59         Event * event = static_cast<Event *>(e);
  60
  61         uint id = event->id();
  62
  63         // Verify that this event is registered
  64         QHash<uint, QString>::const_iterator eventsIt = mEvents.constFind(id);
  65         if (eventsIt == mEvents.constEnd()) {
  66             return true; // We don't know it, but it is an eVaf event and we should handle it
  67         }
  68
  69         // Send the event to all the subscribers
  70         QHash<uint, QVector<QWeakPointer<QObject> > >::const_iterator subscribersIt = mSubscribers.constFind(id);
  71         if (subscribersIt != mSubscribers.constEnd()) {
  72             QVector<QWeakPointer<QObject> > subscribers = *subscribersIt;
  73             int sz = subscribers.size();
  74             for (int i = 0; i < sz; ++i) {
  75
  76                 // Get the subscriber object and make sure that it is still alive
  77                 QWeakPointer<QObject> obj = subscribers.at(i);
  78                 if (obj.isNull()) {
  79                     continue;
  80                 }
  81
  82                 // Notify the subscriber
  83                 bool rval = QCoreApplication::sendEvent(obj.data(), e);
  84
  85                 if (rval) {
  86                     // The event was consumed and should be sent to any other subscribers
  87                     break;
  88                 }
  89             }
  90         }
  91
  92         return true;
  93     }
  94     else
  95         return iEventQueue::event(e);
  96 }
  97
  98 uint EventQueue::registerEvent(QString const & name)
  99 {
 100     uint id = queryEvent(name);
 101
 102     if (id == 0) {
 103         mEvents.insert(mNextEventId, name);
 104         id = mNextEventId++;
 105     }
 106
 107     return id;
 108 }
 109
 110 uint EventQueue::queryEvent(QString const & name) const
 111 {
 112     return mEvents.key(name, 0);
 113 }
 114
 115 void EventQueue::unregisterEvent(uint id)
 116 {
 117     mEvents.remove(id);
 118     mSubscribers.remove(id);
 119 }
 120
 121 uint EventQueue::subscribeEvent(uint id, QObject * obj)
 122 {
 123     if (id == 0)
 124         return 0;
 125
 126     // Only registered events please
 127     if (mEvents.constFind(id) == mEvents.constEnd()) {
 128         return 0;
 129     }
 130
 131     // Check for duplicates
 132     if (mSubscribers[id].indexOf(obj) != -1)
 133         return id;
 134
 135     mSubscribers[id].append(obj);
 136
 137     return id;
 138 }
 139
 140 void EventQueue::unsubscribeEvent(uint id, QObject * obj)
 141 {
 142     if (id == 0)
 143         return;
 144
 145     // Is the event registered?
 146     if (mEvents.constFind(id) == mEvents.constEnd())
 147         return;
 148
 149     // Remove from the list of subscribers
 150     QVector<QWeakPointer<QObject> >::iterator it = mSubscribers[id].begin();
 151     QVector<QWeakPointer<QObject> >::iterator e = mSubscribers[id].end();
 152     while (it != e) {
 153         if (!it->isNull() && it->data() == obj)
 154             it = mSubscribers[id].erase(it);
 155         else
 156             ++it;
 157     }
 158 }
 159
 160 void EventQueue::broadcastEvent(Event * event)
 161 {
 162     QCoreApplication::postEvent(this, event);
 163 }