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Diffstat (limited to 'layout/generic/ScrollbarActivity.cpp')
| -rw-r--r-- | layout/generic/ScrollbarActivity.cpp | 431 |
1 files changed, 431 insertions, 0 deletions
diff --git a/layout/generic/ScrollbarActivity.cpp b/layout/generic/ScrollbarActivity.cpp new file mode 100644 index 0000000000..fb68a71fe0 --- /dev/null +++ b/layout/generic/ScrollbarActivity.cpp @@ -0,0 +1,431 @@ +/* -*- 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 "nsIScrollableFrame.h" +#include "PresShell.h" +#include "nsLayoutUtils.h" +#include "nsScrollbarFrame.h" +#include "nsRefreshDriver.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, but we have to be careful as content descendants of + // our scrollable content aren't necessarily scrolled by our scroll frame + // (if they are out of flow and their containing block is not a descendant + // of our scroll frame) and we don't want those to activate us. + nsIFrame* scrollFrame = do_QueryFrame(mScrollableFrame); + MOZ_ASSERT(scrollFrame); + nsIScrollableFrame* scrollableFrame = do_QueryFrame(mScrollableFrame); + nsCOMPtr<nsIContent> targetContent = + do_QueryInterface(aEvent->GetOriginalTarget()); + nsIFrame* targetFrame = + targetContent ? targetContent->GetPrimaryFrame() : nullptr; + if ((scrollableFrame && scrollableFrame->IsRootScrollFrameOfDocument()) || + !targetFrame || + nsLayoutUtils::IsAncestorFrameCrossDocInProcess( + scrollFrame, targetFrame, + scrollFrame->PresShell()->GetRootFrame())) { + 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 |