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/* -*- 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 "ScrollbarActivity.h"
#include "nsIScrollbarMediator.h"
#include "nsIContent.h"
#include "nsICSSDeclaration.h"
#include "nsIFrame.h"
#include "nsContentUtils.h"
#include "nsAString.h"
#include "nsQueryFrame.h"
#include "nsComponentManagerUtils.h"
#include "nsStyledElement.h"
#include "mozilla/dom/Element.h"
#include "mozilla/dom/Event.h"
#include "mozilla/LookAndFeel.h"
#include "mozilla/StaticPrefs_layout.h"
namespace mozilla {
namespace layout {
using mozilla::dom::Element;
NS_IMPL_ISUPPORTS(ScrollbarActivity, nsIDOMEventListener)
void ScrollbarActivity::QueryLookAndFeelVals() {
// Fade animation constants
mScrollbarFadeBeginDelay =
LookAndFeel::GetInt(LookAndFeel::IntID::ScrollbarFadeBeginDelay);
mScrollbarFadeDuration =
LookAndFeel::GetInt(LookAndFeel::IntID::ScrollbarFadeDuration);
// Controls whether we keep the mouse move listener so we can display the
// scrollbars whenever the user moves the mouse within the scroll area.
mDisplayOnMouseMove =
LookAndFeel::GetInt(LookAndFeel::IntID::ScrollbarDisplayOnMouseMove);
}
void ScrollbarActivity::Destroy() {
StopListeningForScrollbarEvents();
StopListeningForScrollAreaEvents();
UnregisterFromRefreshDriver();
CancelFadeBeginTimer();
}
void ScrollbarActivity::ActivityOccurred() {
ActivityStarted();
ActivityStopped();
}
void ScrollbarActivity::ActivityStarted() {
mNestedActivityCounter++;
CancelFadeBeginTimer();
if (!SetIsFading(false)) {
return;
}
UnregisterFromRefreshDriver();
StartListeningForScrollbarEvents();
StartListeningForScrollAreaEvents();
SetIsActive(true);
NS_ASSERTION(mIsActive, "need to be active during activity");
NS_ASSERTION(!mIsFading, "must not be fading during activity");
}
void ScrollbarActivity::ActivityStopped() {
if (!IsActivityOngoing()) {
// This can happen if there was a frame reconstruction while the activity
// was ongoing. In this case we just do nothing. We should probably handle
// this case better.
return;
}
NS_ASSERTION(mIsActive, "need to be active during activity");
NS_ASSERTION(!mIsFading, "must not be fading during ongoing activity");
mNestedActivityCounter--;
if (!IsActivityOngoing()) {
StartFadeBeginTimer();
NS_ASSERTION(mIsActive, "need to be active right after activity");
NS_ASSERTION(!mIsFading, "must not be fading right after activity");
}
}
NS_IMETHODIMP
ScrollbarActivity::HandleEvent(dom::Event* aEvent) {
if (!mDisplayOnMouseMove && !mIsActive) return NS_OK;
nsAutoString type;
aEvent->GetType(type);
if (type.EqualsLiteral("mousemove")) {
// Mouse motions anywhere in the scrollable frame should keep the
// scrollbars visible.
ActivityOccurred();
return NS_OK;
}
nsCOMPtr<nsIContent> targetContent =
do_QueryInterface(aEvent->GetOriginalTarget());
HandleEventForScrollbar(type, targetContent, GetHorizontalScrollbar(),
&mHScrollbarHovered);
HandleEventForScrollbar(type, targetContent, GetVerticalScrollbar(),
&mVScrollbarHovered);
return NS_OK;
}
void ScrollbarActivity::WillRefresh(TimeStamp aTime) {
NS_ASSERTION(mIsActive, "should only fade while scrollbars are visible");
NS_ASSERTION(!IsActivityOngoing(),
"why weren't we unregistered from the refresh driver when "
"scrollbar activity started?");
NS_ASSERTION(mIsFading, "should only animate fading during fade");
if (!UpdateOpacity(aTime)) {
return;
}
if (!IsStillFading(aTime)) {
EndFade();
}
}
bool ScrollbarActivity::IsStillFading(TimeStamp aTime) {
return !mFadeBeginTime.IsNull() && (aTime - mFadeBeginTime < FadeDuration());
}
void ScrollbarActivity::HandleEventForScrollbar(const nsAString& aType,
nsIContent* aTarget,
Element* aScrollbar,
bool* aStoredHoverState) {
if (!aTarget || !aScrollbar || !aTarget->IsInclusiveDescendantOf(aScrollbar))
return;
if (aType.EqualsLiteral("mousedown")) {
ActivityStarted();
} else if (aType.EqualsLiteral("mouseup")) {
ActivityStopped();
} else if (aType.EqualsLiteral("mouseover") ||
aType.EqualsLiteral("mouseout")) {
bool newHoveredState = aType.EqualsLiteral("mouseover");
if (newHoveredState && !*aStoredHoverState) {
ActivityStarted();
HoveredScrollbar(aScrollbar);
} else if (*aStoredHoverState && !newHoveredState) {
ActivityStopped();
// Don't call HoveredScrollbar(nullptr) here because we want the hover
// attribute to stick until the scrollbars are hidden.
}
*aStoredHoverState = newHoveredState;
}
}
void ScrollbarActivity::StartListeningForScrollbarEvents() {
if (mListeningForScrollbarEvents) return;
mHorizontalScrollbar = GetHorizontalScrollbar();
mVerticalScrollbar = GetVerticalScrollbar();
AddScrollbarEventListeners(mHorizontalScrollbar);
AddScrollbarEventListeners(mVerticalScrollbar);
mListeningForScrollbarEvents = true;
}
void ScrollbarActivity::StopListeningForScrollbarEvents() {
if (!mListeningForScrollbarEvents) return;
RemoveScrollbarEventListeners(mHorizontalScrollbar);
RemoveScrollbarEventListeners(mVerticalScrollbar);
mHorizontalScrollbar = nullptr;
mVerticalScrollbar = nullptr;
mListeningForScrollbarEvents = false;
}
void ScrollbarActivity::StartListeningForScrollAreaEvents() {
if (mListeningForScrollAreaEvents) return;
nsIFrame* scrollArea = do_QueryFrame(mScrollableFrame);
scrollArea->GetContent()->AddEventListener(u"mousemove"_ns, this, true);
mListeningForScrollAreaEvents = true;
}
void ScrollbarActivity::StopListeningForScrollAreaEvents() {
if (!mListeningForScrollAreaEvents) return;
nsIFrame* scrollArea = do_QueryFrame(mScrollableFrame);
scrollArea->GetContent()->RemoveEventListener(u"mousemove"_ns, this, true);
mListeningForScrollAreaEvents = false;
}
void ScrollbarActivity::AddScrollbarEventListeners(
dom::EventTarget* aScrollbar) {
if (aScrollbar) {
aScrollbar->AddEventListener(u"mousedown"_ns, this, true);
aScrollbar->AddEventListener(u"mouseup"_ns, this, true);
aScrollbar->AddEventListener(u"mouseover"_ns, this, true);
aScrollbar->AddEventListener(u"mouseout"_ns, this, true);
}
}
void ScrollbarActivity::RemoveScrollbarEventListeners(
dom::EventTarget* aScrollbar) {
if (aScrollbar) {
aScrollbar->RemoveEventListener(u"mousedown"_ns, this, true);
aScrollbar->RemoveEventListener(u"mouseup"_ns, this, true);
aScrollbar->RemoveEventListener(u"mouseover"_ns, this, true);
aScrollbar->RemoveEventListener(u"mouseout"_ns, this, true);
}
}
void ScrollbarActivity::BeginFade() {
NS_ASSERTION(mIsActive, "can't begin fade when we're already inactive");
NS_ASSERTION(!IsActivityOngoing(),
"why wasn't the fade begin timer cancelled when scrollbar "
"activity started?");
NS_ASSERTION(!mIsFading, "shouldn't be fading just yet");
CancelFadeBeginTimer();
mFadeBeginTime = TimeStamp::Now();
if (!SetIsFading(true)) {
return;
}
RegisterWithRefreshDriver();
NS_ASSERTION(mIsActive, "only fade while scrollbars are visible");
NS_ASSERTION(mIsFading, "should be fading now");
}
void ScrollbarActivity::EndFade() {
NS_ASSERTION(mIsActive, "still need to be active at this point");
NS_ASSERTION(!IsActivityOngoing(),
"why wasn't the fade end timer cancelled when scrollbar "
"activity started?");
if (!SetIsFading(false)) {
return;
}
SetIsActive(false);
UnregisterFromRefreshDriver();
StopListeningForScrollbarEvents();
if (!mDisplayOnMouseMove) {
StopListeningForScrollAreaEvents();
}
NS_ASSERTION(!mIsActive, "should have gone inactive after fade end");
NS_ASSERTION(!mIsFading, "shouldn't be fading anymore");
}
void ScrollbarActivity::RegisterWithRefreshDriver() {
nsRefreshDriver* refreshDriver = GetRefreshDriver();
if (refreshDriver) {
refreshDriver->AddRefreshObserver(this, FlushType::Style,
"Scrollbar fade animation");
}
}
void ScrollbarActivity::UnregisterFromRefreshDriver() {
nsRefreshDriver* refreshDriver = GetRefreshDriver();
if (refreshDriver) {
refreshDriver->RemoveRefreshObserver(this, FlushType::Style);
}
}
static void SetBooleanAttribute(Element* aElement, nsAtom* aAttribute,
bool aValue) {
if (aElement) {
if (aValue) {
aElement->SetAttr(kNameSpaceID_None, aAttribute, u"true"_ns, true);
} else {
aElement->UnsetAttr(kNameSpaceID_None, aAttribute, true);
}
}
}
void ScrollbarActivity::SetIsActive(bool aNewActive) {
if (mIsActive == aNewActive) return;
mIsActive = aNewActive;
if (!mIsActive) {
// Clear sticky scrollbar hover status.
HoveredScrollbar(nullptr);
}
SetBooleanAttribute(GetHorizontalScrollbar(), nsGkAtoms::active, mIsActive);
SetBooleanAttribute(GetVerticalScrollbar(), nsGkAtoms::active, mIsActive);
}
static void SetOpacityOnElement(nsIContent* aContent, double aOpacity) {
if (RefPtr<nsStyledElement> inlineStyleContent =
nsStyledElement::FromNodeOrNull(aContent)) {
nsICSSDeclaration* decl = inlineStyleContent->Style();
nsAutoCString str;
str.AppendFloat(aOpacity);
decl->SetProperty("opacity"_ns, str, EmptyCString(), IgnoreErrors());
}
}
bool ScrollbarActivity::UpdateOpacity(TimeStamp aTime) {
// Avoid division by zero if mScrollbarFadeDuration is zero, just jump
// to the end of the fade animation
double progress = mScrollbarFadeDuration
? ((aTime - mFadeBeginTime) / FadeDuration())
: 1.0;
double opacity = 1.0 - std::max(0.0, std::min(1.0, progress));
// 'this' may be getting destroyed during SetOpacityOnElement calls.
AutoWeakFrame weakFrame((do_QueryFrame(mScrollableFrame)));
SetOpacityOnElement(GetHorizontalScrollbar(), opacity);
if (!weakFrame.IsAlive()) {
return false;
}
SetOpacityOnElement(GetVerticalScrollbar(), opacity);
if (!weakFrame.IsAlive()) {
return false;
}
return true;
}
static void UnsetOpacityOnElement(nsIContent* aContent) {
if (RefPtr<nsStyledElement> inlineStyleContent =
nsStyledElement::FromNodeOrNull(aContent)) {
nsICSSDeclaration* decl = inlineStyleContent->Style();
nsAutoCString dummy;
decl->RemoveProperty("opacity"_ns, dummy, IgnoreErrors());
}
}
bool ScrollbarActivity::SetIsFading(bool aNewFading) {
if (mIsFading == aNewFading) return true;
mIsFading = aNewFading;
if (!mIsFading) {
mFadeBeginTime = TimeStamp();
// 'this' may be getting destroyed during UnsetOpacityOnElement calls.
AutoWeakFrame weakFrame((do_QueryFrame(mScrollableFrame)));
UnsetOpacityOnElement(GetHorizontalScrollbar());
if (!weakFrame.IsAlive()) {
return false;
}
UnsetOpacityOnElement(GetVerticalScrollbar());
if (!weakFrame.IsAlive()) {
return false;
}
}
return true;
}
void ScrollbarActivity::StartFadeBeginTimer() {
if (StaticPrefs::layout_testing_overlay_scrollbars_always_visible()) {
return;
}
if (!mFadeBeginTimer) {
mFadeBeginTimer = NS_NewTimer();
}
mFadeBeginTimer->InitWithNamedFuncCallback(
FadeBeginTimerFired, this, mScrollbarFadeBeginDelay,
nsITimer::TYPE_ONE_SHOT, "ScrollbarActivity::FadeBeginTimerFired");
}
void ScrollbarActivity::CancelFadeBeginTimer() {
if (mFadeBeginTimer) {
mFadeBeginTimer->Cancel();
}
}
static void MaybeInvalidateScrollbarForHover(
Element* aScrollbarToInvalidate, Element* aScrollbarAboutToGetHover) {
if (aScrollbarToInvalidate) {
bool hasHover =
aScrollbarToInvalidate->HasAttr(kNameSpaceID_None, nsGkAtoms::hover);
bool willHaveHover = (aScrollbarAboutToGetHover == aScrollbarToInvalidate);
if (hasHover != willHaveHover) {
if (nsIFrame* f = aScrollbarToInvalidate->GetPrimaryFrame()) {
f->SchedulePaint();
}
}
}
}
void ScrollbarActivity::HoveredScrollbar(Element* aScrollbar) {
Element* vertScrollbar = GetVerticalScrollbar();
Element* horzScrollbar = GetHorizontalScrollbar();
MaybeInvalidateScrollbarForHover(vertScrollbar, aScrollbar);
MaybeInvalidateScrollbarForHover(horzScrollbar, aScrollbar);
SetBooleanAttribute(horzScrollbar, nsGkAtoms::hover, false);
SetBooleanAttribute(vertScrollbar, nsGkAtoms::hover, false);
SetBooleanAttribute(aScrollbar, nsGkAtoms::hover, true);
}
nsRefreshDriver* ScrollbarActivity::GetRefreshDriver() {
nsIFrame* scrollableFrame = do_QueryFrame(mScrollableFrame);
return scrollableFrame->PresContext()->RefreshDriver();
}
Element* ScrollbarActivity::GetScrollbarContent(bool aVertical) {
nsIFrame* box = mScrollableFrame->GetScrollbarBox(aVertical);
return box ? box->GetContent()->AsElement() : nullptr;
}
} // namespace layout
} // namespace mozilla