gecko-dev/gfx/layers/apz/util/ScrollLinkedEffectDetector.cpp

51 строка
1.3 KiB
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/. */
#include "ScrollLinkedEffectDetector.h"
#include "nsIDocument.h"
#include "nsThreadUtils.h"
namespace mozilla {
namespace layers {
uint32_t ScrollLinkedEffectDetector::sDepth = 0;
bool ScrollLinkedEffectDetector::sFoundScrollLinkedEffect = false;
/* static */ void
ScrollLinkedEffectDetector::PositioningPropertyMutated()
{
MOZ_ASSERT(NS_IsMainThread());
if (sDepth > 0) {
// We are inside a scroll event dispatch
sFoundScrollLinkedEffect = true;
}
}
ScrollLinkedEffectDetector::ScrollLinkedEffectDetector(nsIDocument* aDoc)
: mDocument(aDoc)
{
MOZ_ASSERT(NS_IsMainThread());
sDepth++;
}
ScrollLinkedEffectDetector::~ScrollLinkedEffectDetector()
{
sDepth--;
if (sDepth == 0) {
// We have exited all (possibly-nested) scroll event dispatches,
// record whether or not we found an effect, and reset state
if (sFoundScrollLinkedEffect) {
mDocument->ReportHasScrollLinkedEffect();
sFoundScrollLinkedEffect = false;
}
}
}
} // namespace layers
} // namespace mozilla