JUCE/modules/juce_events/broadcasters/juce_ActionBroadcaster.cpp

/*
  ==============================================================================

   This file is part of the JUCE library - "Jules' Utility Class Extensions"
   Copyright 2004-11 by Raw Material Software Ltd.

  ------------------------------------------------------------------------------

   JUCE can be redistributed and/or modified under the terms of the GNU General
   Public License (Version 2), as published by the Free Software Foundation.
   A copy of the license is included in the JUCE distribution, or can be found
   online at www.gnu.org/licenses.

   JUCE is distributed in the hope that it will be useful, but WITHOUT ANY
   WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
   A PARTICULAR PURPOSE.  See the GNU General Public License for more details.

  ------------------------------------------------------------------------------

   To release a closed-source product which uses JUCE, commercial licenses are
   available: visit www.rawmaterialsoftware.com/juce for more information.

  ==============================================================================
*/

class ActionBroadcaster::ActionMessage  : public MessageManager::MessageBase
{
public:
    ActionMessage (const ActionBroadcaster* const broadcaster_,
                   const String& messageText,
                   ActionListener* const listener_) noexcept
        : broadcaster (const_cast <ActionBroadcaster*> (broadcaster_)),
          message (messageText),
          listener (listener_)
    {}

    void messageCallback()
    {
        if (const ActionBroadcaster* const b = broadcaster)
            if (b->actionListeners.contains (listener))
                listener->actionListenerCallback (message);
    }

private:
    WeakReference<ActionBroadcaster> broadcaster;
    const String message;
    ActionListener* const listener;

    JUCE_DECLARE_NON_COPYABLE (ActionMessage)
};

//==============================================================================
ActionBroadcaster::ActionBroadcaster()
{
    // are you trying to create this object before or after juce has been intialised??
    jassert (MessageManager::getInstanceWithoutCreating() != nullptr);
}

ActionBroadcaster::~ActionBroadcaster()
{
    // all event-based objects must be deleted BEFORE juce is shut down!
    jassert (MessageManager::getInstanceWithoutCreating() != nullptr);

    masterReference.clear();
}

void ActionBroadcaster::addActionListener (ActionListener* const listener)
{
    const ScopedLock sl (actionListenerLock);

    if (listener != nullptr)
        actionListeners.add (listener);
}

void ActionBroadcaster::removeActionListener (ActionListener* const listener)
{
    const ScopedLock sl (actionListenerLock);
    actionListeners.removeValue (listener);
}

void ActionBroadcaster::removeAllActionListeners()
{
    const ScopedLock sl (actionListenerLock);
    actionListeners.clear();
}

void ActionBroadcaster::sendActionMessage (const String& message) const
{
    const ScopedLock sl (actionListenerLock);

    for (int i = actionListeners.size(); --i >= 0;)
        (new ActionMessage (this, message, actionListeners.getUnchecked(i)))->post();
}