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Diffstat (limited to '')
| -rw-r--r-- | layout/base/ZoomConstraintsClient.cpp | 258 |
1 files changed, 258 insertions, 0 deletions
diff --git a/layout/base/ZoomConstraintsClient.cpp b/layout/base/ZoomConstraintsClient.cpp new file mode 100644 index 0000000000..4a819f5782 --- /dev/null +++ b/layout/base/ZoomConstraintsClient.cpp @@ -0,0 +1,258 @@ +/* -*- 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 "ZoomConstraintsClient.h" + +#include <inttypes.h> +#include "mozilla/layers/APZCCallbackHelper.h" +#include "mozilla/layers/ScrollableLayerGuid.h" +#include "mozilla/layers/ZoomConstraints.h" +#include "mozilla/Preferences.h" +#include "mozilla/PresShell.h" +#include "mozilla/StaticPrefs_apz.h" +#include "mozilla/dom/Document.h" +#include "mozilla/dom/Event.h" +#include "nsIFrame.h" +#include "nsLayoutUtils.h" +#include "nsPoint.h" +#include "nsView.h" +#include "nsViewportInfo.h" +#include "Units.h" +#include "UnitTransforms.h" + +static mozilla::LazyLogModule sApzZoomLog("apz.zoom"); +#define ZCC_LOG(...) MOZ_LOG(sApzZoomLog, LogLevel::Debug, (__VA_ARGS__)) + +NS_IMPL_ISUPPORTS(ZoomConstraintsClient, nsIDOMEventListener, nsIObserver) + +#define DOM_META_ADDED u"DOMMetaAdded"_ns +#define DOM_META_CHANGED u"DOMMetaChanged"_ns +#define FULLSCREEN_CHANGED u"fullscreenchange"_ns +#define BEFORE_FIRST_PAINT "before-first-paint"_ns +#define NS_PREF_CHANGED "nsPref:changed"_ns + +using namespace mozilla; +using namespace mozilla::dom; +using namespace mozilla::layers; + +ZoomConstraintsClient::ZoomConstraintsClient() + : mDocument(nullptr), + mPresShell(nullptr), + mZoomConstraints(false, false, CSSToParentLayerScale(1.f), + CSSToParentLayerScale(1.f)) {} + +ZoomConstraintsClient::~ZoomConstraintsClient() = default; + +static nsIWidget* GetWidget(PresShell* aPresShell) { + if (!aPresShell) { + return nullptr; + } + if (nsIFrame* rootFrame = aPresShell->GetRootFrame()) { +#if defined(MOZ_WIDGET_ANDROID) || defined(MOZ_WIDGET_UIKIT) + return rootFrame->GetNearestWidget(); +#else + if (nsView* view = rootFrame->GetView()) { + return view->GetWidget(); + } +#endif + } + return nullptr; +} + +void ZoomConstraintsClient::Destroy() { + if (!(mPresShell && mDocument)) { + return; + } + + ZCC_LOG("Destroying %p\n", this); + + if (mEventTarget) { + mEventTarget->RemoveEventListener(DOM_META_ADDED, this, false); + mEventTarget->RemoveEventListener(DOM_META_CHANGED, this, false); + mEventTarget->RemoveSystemEventListener(FULLSCREEN_CHANGED, this, false); + mEventTarget = nullptr; + } + + nsCOMPtr<nsIObserverService> observerService = + mozilla::services::GetObserverService(); + if (observerService) { + observerService->RemoveObserver(this, BEFORE_FIRST_PAINT.Data()); + } + + Preferences::RemoveObserver(this, "browser.ui.zoom.force-user-scalable"); + + if (mGuid) { + if (nsIWidget* widget = GetWidget(mPresShell)) { + ZCC_LOG("Sending null constraints in %p for { %u, %" PRIu64 " }\n", this, + mGuid->mPresShellId, mGuid->mScrollId); + widget->UpdateZoomConstraints(mGuid->mPresShellId, mGuid->mScrollId, + Nothing()); + mGuid = Nothing(); + } + } + + mDocument = nullptr; + mPresShell = nullptr; +} + +void ZoomConstraintsClient::Init(PresShell* aPresShell, Document* aDocument) { + if (!(aPresShell && aDocument)) { + return; + } + + mPresShell = aPresShell; + mDocument = aDocument; + + if (nsCOMPtr<nsPIDOMWindowOuter> window = mDocument->GetWindow()) { + mEventTarget = window->GetParentTarget(); + } + if (mEventTarget) { + mEventTarget->AddEventListener(DOM_META_ADDED, this, false); + mEventTarget->AddEventListener(DOM_META_CHANGED, this, false); + mEventTarget->AddSystemEventListener(FULLSCREEN_CHANGED, this, false); + } + + nsCOMPtr<nsIObserverService> observerService = + mozilla::services::GetObserverService(); + if (observerService) { + observerService->AddObserver(this, BEFORE_FIRST_PAINT.Data(), false); + } + + Preferences::AddStrongObserver(this, "browser.ui.zoom.force-user-scalable"); +} + +NS_IMETHODIMP +ZoomConstraintsClient::HandleEvent(dom::Event* event) { + nsAutoString type; + event->GetType(type); + + if (type.Equals(DOM_META_ADDED)) { + ZCC_LOG("Got a dom-meta-added event in %p\n", this); + RefreshZoomConstraints(); + } else if (type.Equals(DOM_META_CHANGED)) { + ZCC_LOG("Got a dom-meta-changed event in %p\n", this); + RefreshZoomConstraints(); + } else if (type.Equals(FULLSCREEN_CHANGED)) { + ZCC_LOG("Got a fullscreen-change event in %p\n", this); + RefreshZoomConstraints(); + } + + return NS_OK; +} + +NS_IMETHODIMP +ZoomConstraintsClient::Observe(nsISupports* aSubject, const char* aTopic, + const char16_t* aData) { + if (SameCOMIdentity(aSubject, ToSupports(mDocument)) && + BEFORE_FIRST_PAINT.EqualsASCII(aTopic)) { + ZCC_LOG("Got a before-first-paint event in %p\n", this); + RefreshZoomConstraints(); + } else if (NS_PREF_CHANGED.EqualsASCII(aTopic)) { + ZCC_LOG("Got a pref-change event in %p\n", this); + // We need to run this later because all the pref change listeners need + // to execute before we can be guaranteed that + // StaticPrefs::browser_ui_zoom_force_user_scalable() returns the updated + // value. + + RefPtr<nsRunnableMethod<ZoomConstraintsClient>> event = + NewRunnableMethod("ZoomConstraintsClient::RefreshZoomConstraints", this, + &ZoomConstraintsClient::RefreshZoomConstraints); + mDocument->Dispatch(TaskCategory::Other, event.forget()); + } + return NS_OK; +} + +void ZoomConstraintsClient::ScreenSizeChanged() { + ZCC_LOG("Got a screen-size change notification in %p\n", this); + RefreshZoomConstraints(); +} + +static mozilla::layers::ZoomConstraints ComputeZoomConstraintsFromViewportInfo( + const nsViewportInfo& aViewportInfo, Document* aDocument) { + mozilla::layers::ZoomConstraints constraints; + constraints.mAllowZoom = aViewportInfo.IsZoomAllowed() && + nsLayoutUtils::AllowZoomingForDocument(aDocument); + constraints.mAllowDoubleTapZoom = + constraints.mAllowZoom && StaticPrefs::apz_allow_double_tap_zooming(); + if (constraints.mAllowZoom) { + constraints.mMinZoom.scale = aViewportInfo.GetMinZoom().scale; + constraints.mMaxZoom.scale = aViewportInfo.GetMaxZoom().scale; + } else { + constraints.mMinZoom.scale = aViewportInfo.GetDefaultZoom().scale; + constraints.mMaxZoom.scale = aViewportInfo.GetDefaultZoom().scale; + } + return constraints; +} + +void ZoomConstraintsClient::RefreshZoomConstraints() { + mZoomConstraints = ZoomConstraints(false, false, CSSToParentLayerScale(1.f), + CSSToParentLayerScale(1.f)); + + nsIWidget* widget = GetWidget(mPresShell); + if (!widget) { + return; + } + + uint32_t presShellId = 0; + ScrollableLayerGuid::ViewID viewId = ScrollableLayerGuid::NULL_SCROLL_ID; + bool scrollIdentifiersValid = + APZCCallbackHelper::GetOrCreateScrollIdentifiers( + mDocument->GetDocumentElement(), &presShellId, &viewId); + if (!scrollIdentifiersValid) { + return; + } + + LayoutDeviceIntSize screenSize; + if (!nsLayoutUtils::GetContentViewerSize(mPresShell->GetPresContext(), + screenSize)) { + return; + } + + nsViewportInfo viewportInfo = mDocument->GetViewportInfo(ViewAs<ScreenPixel>( + screenSize, PixelCastJustification::LayoutDeviceIsScreenForBounds)); + + mZoomConstraints = + ComputeZoomConstraintsFromViewportInfo(viewportInfo, mDocument); + + if (mDocument->Fullscreen()) { + ZCC_LOG("%p is in fullscreen, disallowing zooming\n", this); + mZoomConstraints.mAllowZoom = false; + mZoomConstraints.mAllowDoubleTapZoom = false; + } + + if (mZoomConstraints.mAllowDoubleTapZoom) { + // If the CSS viewport is narrower than the screen (i.e. width <= + // device-width) then we disable double-tap-to-zoom behaviour. + CSSToLayoutDeviceScale scale = + mPresShell->GetPresContext()->CSSToDevPixelScale(); + if ((viewportInfo.GetSize() * scale).width <= screenSize.width) { + mZoomConstraints.mAllowDoubleTapZoom = false; + } + } + + // We only ever create a ZoomConstraintsClient for an RCD, so the RSF of + // the presShell must be the RCD-RSF (if it exists). + MOZ_ASSERT(mPresShell->GetPresContext()->IsRootContentDocumentCrossProcess()); + if (nsIScrollableFrame* rcdrsf = + mPresShell->GetRootScrollFrameAsScrollable()) { + ZCC_LOG("Notifying RCD-RSF that it is zoomable: %d\n", + mZoomConstraints.mAllowZoom); + rcdrsf->SetZoomableByAPZ(mZoomConstraints.mAllowZoom); + } + + ScrollableLayerGuid newGuid(LayersId{0}, presShellId, viewId); + if (mGuid && mGuid.value() != newGuid) { + ZCC_LOG("Clearing old constraints in %p for { %u, %" PRIu64 " }\n", this, + mGuid->mPresShellId, mGuid->mScrollId); + // If the guid changes, send a message to clear the old one + widget->UpdateZoomConstraints(mGuid->mPresShellId, mGuid->mScrollId, + Nothing()); + } + mGuid = Some(newGuid); + ZCC_LOG("Sending constraints %s in %p for { %u, %" PRIu64 " }\n", + ToString(mZoomConstraints).c_str(), this, presShellId, viewId); + widget->UpdateZoomConstraints(presShellId, viewId, Some(mZoomConstraints)); +} |