webrtc_m130/webrtc/api/notifier.h
Edward Lemur c20978e581 Rename webrtc/base -> webrtc/rtc_base
NOPRESUBMIT=True # cpplint errors that aren't caused by this CL.
NOTRY=True
NOTREECHECKS=True
TBR=kwiberg@webrtc.org, kjellander@webrtc.org

Bug: webrtc:7634
Change-Id: I3cca0fbaa807b563c95979cccd6d1bec32055f36
Reviewed-on: https://chromium-review.googlesource.com/562156
Commit-Queue: Edward Lemur <ehmaldonado@webrtc.org>
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#18919}
2017-07-06 19:11:40 +00:00

62 lines
1.7 KiB
C++

/*
* Copyright 2011 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#ifndef WEBRTC_API_NOTIFIER_H_
#define WEBRTC_API_NOTIFIER_H_
#include <list>
#include "webrtc/api/mediastreaminterface.h"
#include "webrtc/rtc_base/checks.h"
namespace webrtc {
// Implements a template version of a notifier.
// TODO(deadbeef): This is an implementation detail; move out of api/.
template <class T>
class Notifier : public T {
public:
Notifier() {
}
virtual void RegisterObserver(ObserverInterface* observer) {
RTC_DCHECK(observer != nullptr);
observers_.push_back(observer);
}
virtual void UnregisterObserver(ObserverInterface* observer) {
for (std::list<ObserverInterface*>::iterator it = observers_.begin();
it != observers_.end(); it++) {
if (*it == observer) {
observers_.erase(it);
break;
}
}
}
void FireOnChanged() {
// Copy the list of observers to avoid a crash if the observer object
// unregisters as a result of the OnChanged() call. If the same list is used
// UnregisterObserver will affect the list make the iterator invalid.
std::list<ObserverInterface*> observers = observers_;
for (std::list<ObserverInterface*>::iterator it = observers.begin();
it != observers.end(); ++it) {
(*it)->OnChanged();
}
}
protected:
std::list<ObserverInterface*> observers_;
};
} // namespace webrtc
#endif // WEBRTC_API_NOTIFIER_H_