1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/accessible/src/base/EventQueue.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,88 @@
1.4 +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.6 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.7 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.8 +
1.9 +#ifndef mozilla_a11y_EventQueue_h_
1.10 +#define mozilla_a11y_EventQueue_h_
1.11 +
1.12 +#include "AccEvent.h"
1.13 +
1.14 +namespace mozilla {
1.15 +namespace a11y {
1.16 +
1.17 +class DocAccessible;
1.18 +
1.19 +/**
1.20 + * Used to organize and coalesce pending events.
1.21 + */
1.22 +class EventQueue
1.23 +{
1.24 +protected:
1.25 + EventQueue(DocAccessible* aDocument) : mDocument(aDocument) { }
1.26 +
1.27 + /**
1.28 + * Put an accessible event into the queue to process it later.
1.29 + */
1.30 + bool PushEvent(AccEvent* aEvent);
1.31 +
1.32 + /**
1.33 + * Process events from the queue and fires events.
1.34 + */
1.35 + void ProcessEventQueue();
1.36 +
1.37 +private:
1.38 + EventQueue(const EventQueue&) MOZ_DELETE;
1.39 + EventQueue& operator = (const EventQueue&) MOZ_DELETE;
1.40 +
1.41 + // Event queue processing
1.42 + /**
1.43 + * Coalesce redundant events from the queue.
1.44 + */
1.45 + void CoalesceEvents();
1.46 +
1.47 + /**
1.48 + * Coalesce events from the same subtree.
1.49 + */
1.50 + void CoalesceReorderEvents(AccEvent* aTailEvent);
1.51 +
1.52 + /**
1.53 + * Coalesce two selection change events within the same select control.
1.54 + */
1.55 + void CoalesceSelChangeEvents(AccSelChangeEvent* aTailEvent,
1.56 + AccSelChangeEvent* aThisEvent,
1.57 + uint32_t aThisIndex);
1.58 +
1.59 + /**
1.60 + * Coalesce text change events caused by sibling hide events.
1.61 + */
1.62 + void CoalesceTextChangeEventsFor(AccHideEvent* aTailEvent,
1.63 + AccHideEvent* aThisEvent);
1.64 + void CoalesceTextChangeEventsFor(AccShowEvent* aTailEvent,
1.65 + AccShowEvent* aThisEvent);
1.66 +
1.67 + /**
1.68 + * Create text change event caused by hide or show event. When a node is
1.69 + * hidden/removed or shown/appended, the text in an ancestor hyper text will
1.70 + * lose or get new characters.
1.71 + */
1.72 + void CreateTextChangeEventFor(AccMutationEvent* aEvent);
1.73 +
1.74 +protected:
1.75 +
1.76 + /**
1.77 + * The document accessible reference owning this queue.
1.78 + */
1.79 + DocAccessible* mDocument;
1.80 +
1.81 + /**
1.82 + * Pending events array. Don't make this an nsAutoTArray; we use
1.83 + * SwapElements() on it.
1.84 + */
1.85 + nsTArray<nsRefPtr<AccEvent> > mEvents;
1.86 +};
1.87 +
1.88 +} // namespace a11y
1.89 +} // namespace mozilla
1.90 +
1.91 +#endif // mozilla_a11y_EventQueue_h_
