/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ /* 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 "FrameMetrics.h" #include "gfxPrefs.h" #include "LayersLogging.h" #include "mozilla/layers/APZCCallbackHelper.h" #include "mozilla/Preferences.h" #include "mozilla/dom/Event.h" #include "nsDocument.h" #include "nsIFrame.h" #include "nsLayoutUtils.h" #include "nsPoint.h" #include "nsPresShell.h" #include "nsView.h" #include "nsViewportInfo.h" #include "Units.h" #include "UnitTransforms.h" #define ZCC_LOG(...) // #define ZCC_LOG(...) printf_stderr("ZCC: " __VA_ARGS__) NS_IMPL_ISUPPORTS(ZoomConstraintsClient, nsIDOMEventListener, nsIObserver) static const nsLiteralString DOM_META_ADDED = NS_LITERAL_STRING("DOMMetaAdded"); static const nsLiteralString DOM_META_CHANGED = NS_LITERAL_STRING("DOMMetaChanged"); static const nsLiteralString FULLSCREEN_CHANGED = NS_LITERAL_STRING("fullscreenchange"); static const nsLiteralCString BEFORE_FIRST_PAINT = NS_LITERAL_CSTRING("before-first-paint"); static const nsLiteralCString NS_PREF_CHANGED = NS_LITERAL_CSTRING("nsPref:changed"); using namespace mozilla; using namespace mozilla::layers; ZoomConstraintsClient::ZoomConstraintsClient() : mDocument(nullptr), mPresShell(nullptr) { } ZoomConstraintsClient::~ZoomConstraintsClient() { } static nsIWidget* GetWidget(nsIPresShell* aShell) { if (!aShell) { return nullptr; } if (nsIFrame* rootFrame = aShell->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(nsIPresShell* aPresShell, nsIDocument* 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(nsIDOMEvent* 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, 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 gfxPrefs::ForceUserScalable() // returns the updated value. NS_DispatchToMainThread(NewRunnableMethod( this, &ZoomConstraintsClient::RefreshZoomConstraints)); } return NS_OK; } void ZoomConstraintsClient::ScreenSizeChanged() { ZCC_LOG("Got a screen-size change notification in %p\n", this); RefreshZoomConstraints(); } mozilla::layers::ZoomConstraints ComputeZoomConstraintsFromViewportInfo(const nsViewportInfo& aViewportInfo) { mozilla::layers::ZoomConstraints constraints; constraints.mAllowZoom = aViewportInfo.IsZoomAllowed() && gfxPrefs::APZAllowZooming(); constraints.mAllowDoubleTapZoom = constraints.mAllowZoom; 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() { nsIWidget* widget = GetWidget(mPresShell); if (!widget) { return; } uint32_t presShellId = 0; FrameMetrics::ViewID viewId = FrameMetrics::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)); mozilla::layers::ZoomConstraints zoomConstraints = ComputeZoomConstraintsFromViewportInfo(viewportInfo); if (mDocument->Fullscreen()) { ZCC_LOG("%p is in fullscreen, disallowing zooming\n", this); zoomConstraints.mAllowZoom = false; zoomConstraints.mAllowDoubleTapZoom = false; } if (zoomConstraints.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) { zoomConstraints.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()->IsRootContentDocument()); if (nsIScrollableFrame* rcdrsf = mPresShell->GetRootScrollFrameAsScrollable()) { ZCC_LOG("Notifying RCD-RSF that it is zoomable: %d\n", zoomConstraints.mAllowZoom); rcdrsf->SetZoomableByAPZ(zoomConstraints.mAllowZoom); } ScrollableLayerGuid newGuid(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", Stringify(zoomConstraints).c_str(), this, presShellId, viewId); widget->UpdateZoomConstraints(presShellId, viewId, Some(zoomConstraints)); }