Quelle nsRefreshObservers.h Sprache: C

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/*
* Code to notify things that animate before a refresh, at an appropriate
* refresh rate.  (Perhaps temporary, until replaced by compositor.)
*/

#ifndef LAYOUT_BASE_NSREFRESHOBSERVERS_H_
#define LAYOUT_BASE_NSREFRESHOBSERVERS_H_

#include <functional>

#include "mozilla/Attributes.h"
#include "mozilla/TimeStamp.h"
#include "nsISupports.h"

class nsPresContext;

namespace mozilla {
class AnimationEventDispatcher;
class PendingFullscreenEvent;
class PresShell;
class RefreshDriverTimer;
}  // namespace mozilla

/**
* An abstract base class to be implemented by callers wanting to be
* notified at refresh times.  When nothing needs to be painted, callers
* may not be notified.
*/
class nsARefreshObserver {
public:
  // AddRef and Release signatures that match nsISupports.  Implementors
  // must implement reference counting, and those that do implement
  // nsISupports will already have methods with the correct signature.
  //
  // The refresh driver does NOT hold references to refresh observers
  // except while it is notifying them.
  NS_INLINE_DECL_PURE_VIRTUAL_REFCOUNTING

  MOZ_CAN_RUN_SCRIPT virtual void WillRefresh(mozilla::TimeStamp aTime) = 0;

#ifdef DEBUG
  // Count of the active registrations we currently have with nsRefreshDrivers.
  // This is incremented in nsRefreshDriver::AddRefreshObserver, decremented in
  // nsRefreshDriver::RemoveRefreshObserver. No other code should modify this.
  // We expect this to be 0 when we're destructed.
  int32_t mRegistrationCount = 0;

  // Virtual destructor to enforce the mRegistrationCount invariant.
  virtual ~nsARefreshObserver() {
    MOZ_ASSERT(mRegistrationCount == 0,
               "Refresh observer AddRefreshObserver/RemoveRefreshObserver "
               "calls should have balanced out to zero");
  }
#endif  // DEBUG
};

/**
* An abstract base class to be implemented by callers wanting to be notified
* that a refresh has occurred. Callers must ensure an observer is removed
* before it is destroyed.
*/
class nsAPostRefreshObserver {
public:
  virtual void DidRefresh() = 0;
};

namespace mozilla {

/**
* A wrapper for nsAPostRefreshObserver that's refcounted and might unregister
* itself after firing.
*
* Note, while the observer unregisters itself, the registering still needs to
* be done by the caller.
*/
class ManagedPostRefreshObserver : public nsAPostRefreshObserver {
public:
  // Whether the post-refresh observer should be unregistered after it has
  // fired.
  enum class Unregister : bool { No, Yes };
  using Action = std::function<Unregister(bool aWasCanceled)>;
  NS_INLINE_DECL_REFCOUNTING(ManagedPostRefreshObserver)
  ManagedPostRefreshObserver(nsPresContext*, Action&&);
  explicit ManagedPostRefreshObserver(nsPresContext*);
  void DidRefresh() override;
  void Cancel();

protected:
  virtual ~ManagedPostRefreshObserver();
  RefPtr<nsPresContext> mPresContext;
  Action mAction;
};

}  // namespace mozilla

#endif

quality100%

¤ Dauer der Verarbeitung: 0.1 Sekunden (vorverarbeitet) ¤

Wurzel

Suchen

Beweissystem der NASA

Beweissystem Isabelle

NIST Cobol Testsuite

Cephes Mathematical Library

Wiener Entwicklungsmethode

Haftungshinweis

Die Informationen auf dieser Webseite wurden nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit, noch Qualität der bereit gestellten Informationen zugesichert.

Bemerkung:

Die farbliche Syntaxdarstellung ist noch experimentell.