diff options
Diffstat (limited to 'gfx/layers/apz/util/APZEventState.cpp')
| -rw-r--r-- | gfx/layers/apz/util/APZEventState.cpp | 567 |
1 files changed, 567 insertions, 0 deletions
diff --git a/gfx/layers/apz/util/APZEventState.cpp b/gfx/layers/apz/util/APZEventState.cpp new file mode 100644 index 0000000000..7384296f45 --- /dev/null +++ b/gfx/layers/apz/util/APZEventState.cpp @@ -0,0 +1,567 @@ +/* -*- 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 "APZEventState.h" + +#include <utility> + +#include "APZCCallbackHelper.h" +#include "ActiveElementManager.h" +#include "TouchManager.h" +#include "mozilla/Assertions.h" +#include "mozilla/BasicEvents.h" +#include "mozilla/dom/Document.h" +#include "mozilla/EventForwards.h" +#include "mozilla/IntegerPrintfMacros.h" +#include "mozilla/PositionedEventTargeting.h" +#include "mozilla/Preferences.h" +#include "mozilla/PresShell.h" +#include "mozilla/StaticPrefs_dom.h" +#include "mozilla/StaticPrefs_ui.h" +#include "mozilla/ToString.h" +#include "mozilla/TouchEvents.h" +#include "mozilla/ViewportUtils.h" +#include "mozilla/dom/BrowserChild.h" +#include "mozilla/dom/MouseEventBinding.h" +#include "mozilla/layers/APZCCallbackHelper.h" +#include "mozilla/layers/IAPZCTreeManager.h" +#include "mozilla/widget/nsAutoRollup.h" +#include "nsCOMPtr.h" +#include "nsContentUtils.h" +#include "nsDocShell.h" +#include "nsIDOMWindowUtils.h" +#include "nsINamed.h" +#include "nsIScrollableFrame.h" +#include "nsIScrollbarMediator.h" +#include "nsIWeakReferenceUtils.h" +#include "nsIWidget.h" +#include "nsLayoutUtils.h" +#include "nsQueryFrame.h" + +static mozilla::LazyLogModule sApzEvtLog("apz.eventstate"); +#define APZES_LOG(...) MOZ_LOG(sApzEvtLog, LogLevel::Debug, (__VA_ARGS__)) + +// Static helper functions +namespace { + +int32_t WidgetModifiersToDOMModifiers(mozilla::Modifiers aModifiers) { + int32_t result = 0; + if (aModifiers & mozilla::MODIFIER_SHIFT) { + result |= nsIDOMWindowUtils::MODIFIER_SHIFT; + } + if (aModifiers & mozilla::MODIFIER_CONTROL) { + result |= nsIDOMWindowUtils::MODIFIER_CONTROL; + } + if (aModifiers & mozilla::MODIFIER_ALT) { + result |= nsIDOMWindowUtils::MODIFIER_ALT; + } + if (aModifiers & mozilla::MODIFIER_META) { + result |= nsIDOMWindowUtils::MODIFIER_META; + } + if (aModifiers & mozilla::MODIFIER_ALTGRAPH) { + result |= nsIDOMWindowUtils::MODIFIER_ALTGRAPH; + } + if (aModifiers & mozilla::MODIFIER_CAPSLOCK) { + result |= nsIDOMWindowUtils::MODIFIER_CAPSLOCK; + } + if (aModifiers & mozilla::MODIFIER_FN) { + result |= nsIDOMWindowUtils::MODIFIER_FN; + } + if (aModifiers & mozilla::MODIFIER_FNLOCK) { + result |= nsIDOMWindowUtils::MODIFIER_FNLOCK; + } + if (aModifiers & mozilla::MODIFIER_NUMLOCK) { + result |= nsIDOMWindowUtils::MODIFIER_NUMLOCK; + } + if (aModifiers & mozilla::MODIFIER_SCROLLLOCK) { + result |= nsIDOMWindowUtils::MODIFIER_SCROLLLOCK; + } + if (aModifiers & mozilla::MODIFIER_SYMBOL) { + result |= nsIDOMWindowUtils::MODIFIER_SYMBOL; + } + if (aModifiers & mozilla::MODIFIER_SYMBOLLOCK) { + result |= nsIDOMWindowUtils::MODIFIER_SYMBOLLOCK; + } + return result; +} + +} // namespace + +namespace mozilla { +namespace layers { + +APZEventState::APZEventState(nsIWidget* aWidget, + ContentReceivedInputBlockCallback&& aCallback) + : mWidget(nullptr) // initialized in constructor body + , + mActiveElementManager(new ActiveElementManager()), + mContentReceivedInputBlockCallback(std::move(aCallback)), + mPendingTouchPreventedResponse(false), + mPendingTouchPreventedBlockId(0), + mEndTouchIsClick(false), + mFirstTouchCancelled(false), + mTouchEndCancelled(false), + mReceivedNonTouchStart(false), + mTouchStartPrevented(false), + mLastTouchIdentifier(0) { + nsresult rv; + mWidget = do_GetWeakReference(aWidget, &rv); + MOZ_ASSERT(NS_SUCCEEDED(rv), + "APZEventState constructed with a widget that" + " does not support weak references. APZ will NOT work!"); +} + +APZEventState::~APZEventState() = default; + +void APZEventState::ProcessSingleTap(const CSSPoint& aPoint, + const CSSToLayoutDeviceScale& aScale, + Modifiers aModifiers, int32_t aClickCount, + uint64_t aInputBlockId) { + APZES_LOG("Handling single tap at %s with %d\n", ToString(aPoint).c_str(), + mTouchEndCancelled); + + RefPtr<nsIContent> touchRollup = GetTouchRollup(); + mTouchRollup = nullptr; + + nsCOMPtr<nsIWidget> widget = GetWidget(); + if (!widget) { + return; + } + + if (mTouchEndCancelled) { + return; + } + + nsCOMPtr<nsIWidget> localWidget = do_QueryReferent(mWidget); + if (localWidget) { + widget::nsAutoRollup rollup(touchRollup); + APZCCallbackHelper::FireSingleTapEvent(aPoint * aScale, aModifiers, + aClickCount, localWidget); + } + + mActiveElementManager->ProcessSingleTap(); +} + +PreventDefaultResult APZEventState::FireContextmenuEvents( + PresShell* aPresShell, const CSSPoint& aPoint, + const CSSToLayoutDeviceScale& aScale, Modifiers aModifiers, + const nsCOMPtr<nsIWidget>& aWidget) { + // Suppress retargeting for mouse events generated by a long-press + EventRetargetSuppression suppression; + + // Synthesize mousemove event for allowing users to emulate to move mouse + // cursor over the element. As a result, users can open submenu UI which + // is opened when mouse cursor is moved over a link (i.e., it's a case that + // users cannot stay in the page after tapping it). So, this improves + // accessibility in websites which are designed for desktop. + // Note that we don't need to check whether mousemove event is consumed or + // not because Chrome also ignores the result. + APZCCallbackHelper::DispatchSynthesizedMouseEvent( + eMouseMove, aPoint * aScale, aModifiers, 0 /* clickCount */, aWidget); + + // Converting the modifiers to DOM format for the DispatchMouseEvent call + // is the most useless thing ever because nsDOMWindowUtils::SendMouseEvent + // just converts them back to widget format, but that API has many callers, + // including in JS code, so it's not trivial to change. + CSSPoint point = CSSPoint::FromAppUnits( + ViewportUtils::VisualToLayout(CSSPoint::ToAppUnits(aPoint), aPresShell)); + PreventDefaultResult preventDefaultResult = + APZCCallbackHelper::DispatchMouseEvent( + aPresShell, u"contextmenu"_ns, point, 2, 1, + WidgetModifiersToDOMModifiers(aModifiers), + dom::MouseEvent_Binding::MOZ_SOURCE_TOUCH, + 0 /* Use the default value here. */); + + APZES_LOG("Contextmenu event %s\n", ToString(preventDefaultResult).c_str()); + if (preventDefaultResult != PreventDefaultResult::No) { + // If the contextmenu event was handled then we're showing a contextmenu, + // and so we should remove any activation + mActiveElementManager->ClearActivation(); +#ifndef XP_WIN + } else { + // If the contextmenu wasn't consumed, fire the eMouseLongTap event. + nsEventStatus status = APZCCallbackHelper::DispatchSynthesizedMouseEvent( + eMouseLongTap, aPoint * aScale, aModifiers, + /*clickCount*/ 1, aWidget); + APZES_LOG("eMouseLongTap event %s\n", ToString(status).c_str()); +#endif + } + + return preventDefaultResult; +} + +void APZEventState::ProcessLongTap(PresShell* aPresShell, + const CSSPoint& aPoint, + const CSSToLayoutDeviceScale& aScale, + Modifiers aModifiers, + uint64_t aInputBlockId) { + APZES_LOG("Handling long tap at %s block id %" PRIu64 "\n", + ToString(aPoint).c_str(), aInputBlockId); + + nsCOMPtr<nsIWidget> widget = GetWidget(); + if (!widget) { + return; + } + + // If the touch block is waiting for a content response, send one now. + // Bug 1848736: Why is a content response needed here? Can it be removed? + // However, do not clear |mPendingTouchPreventedResponse|, because APZ will + // wait for an additional content response before processing touch-move + // events (since the first touch-move could still be prevented, and that + // should prevent the touch block from being processed). + if (mPendingTouchPreventedResponse) { + APZES_LOG("Sending response %d for pending guid: %s block id: %" PRIu64 + " due to long tap\n", + false, ToString(mPendingTouchPreventedGuid).c_str(), + mPendingTouchPreventedBlockId); + mContentReceivedInputBlockCallback(mPendingTouchPreventedBlockId, false); + } + +#ifdef XP_WIN + // On Windows, we fire the contextmenu events when the user lifts their + // finger, in keeping with the platform convention. This happens in the + // ProcessLongTapUp function. However, we still fire the eMouseLongTap event + // at this time, because things like text selection or dragging may want + // to know about it. + APZCCallbackHelper::DispatchSynthesizedMouseEvent( + eMouseLongTap, aPoint * aScale, aModifiers, /*clickCount*/ 1, widget); +#else + PreventDefaultResult preventDefaultResult = + FireContextmenuEvents(aPresShell, aPoint, aScale, aModifiers, widget); +#endif + + const bool contextmenuOpen = +#ifdef XP_WIN + // On Windows context menu will never be opened by long tap events, the + // menu will open after the user lifts their finger. + false; +#elif defined(MOZ_WIDGET_ANDROID) + // On Android, GeckoView calls preventDefault() in a JSActor + // (ContentDelegateChild.jsm) when opening context menu so that we can + // tell whether contextmenu opens in response to the contextmenu event by + // checking where preventDefault() got called. + preventDefaultResult == PreventDefaultResult::ByChrome; +#else + // On desktop platforms (other than Windows) unlike Android, context menu + // can be opened anywhere even if, for example, there's no link under the + // touch point. So we can assume that "not preventDefault" means a context + // menu is open. + preventDefaultResult == PreventDefaultResult::No; +#endif + // Assuming that contextmenuOpen=true here means a context menu was opened, it + // will be treated as "preventDefaulted" in APZ. + mContentReceivedInputBlockCallback(aInputBlockId, contextmenuOpen); + + if (contextmenuOpen) { + // Also send a touchcancel to content + // a) on Android if browser's contextmenu is open + // b) on desktop platforms other than Windows if browser's contextmenu is + // open + // so that listeners that might be waiting for a touchend don't trigger. + WidgetTouchEvent cancelTouchEvent(true, eTouchCancel, widget.get()); + cancelTouchEvent.mModifiers = aModifiers; + auto ldPoint = LayoutDeviceIntPoint::Round(aPoint * aScale); + cancelTouchEvent.mTouches.AppendElement(new mozilla::dom::Touch( + mLastTouchIdentifier, ldPoint, LayoutDeviceIntPoint(), 0, 0)); + APZCCallbackHelper::DispatchWidgetEvent(cancelTouchEvent); + } +} + +void APZEventState::ProcessLongTapUp(PresShell* aPresShell, + const CSSPoint& aPoint, + const CSSToLayoutDeviceScale& aScale, + Modifiers aModifiers) { +#ifdef XP_WIN + nsCOMPtr<nsIWidget> widget = GetWidget(); + if (widget) { + FireContextmenuEvents(aPresShell, aPoint, aScale, aModifiers, widget); + } +#endif +} + +void APZEventState::ProcessTouchEvent( + const WidgetTouchEvent& aEvent, const ScrollableLayerGuid& aGuid, + uint64_t aInputBlockId, nsEventStatus aApzResponse, + nsEventStatus aContentResponse, + nsTArray<TouchBehaviorFlags>&& aAllowedTouchBehaviors) { + if (aEvent.mMessage == eTouchStart && aEvent.mTouches.Length() > 0) { + mActiveElementManager->SetTargetElement( + aEvent.mTouches[0]->GetOriginalTarget()); + mLastTouchIdentifier = aEvent.mTouches[0]->Identifier(); + } + if (aEvent.mMessage == eTouchStart) { + // We get the allowed touch behaviors on a touchstart, but may not actually + // use them until the first touchmove, so we stash them in a member + // variable. + mTouchBlockAllowedBehaviors = std::move(aAllowedTouchBehaviors); + } + + bool isTouchPrevented = aContentResponse == nsEventStatus_eConsumeNoDefault; + bool mayNeedPointerCancelEvent = false; + APZES_LOG("Handling event type %d isPrevented=%d\n", aEvent.mMessage, + isTouchPrevented); + switch (aEvent.mMessage) { + case eTouchStart: { + mTouchEndCancelled = false; + mReceivedNonTouchStart = false; + mTouchRollup = do_GetWeakReference(widget::nsAutoRollup::GetLastRollup()); + + SendPendingTouchPreventedResponse(false); + // The above call may have sent a message to APZ if we get two + // TOUCH_STARTs in a row and just responded to the first one. + + // We're about to send a response back to APZ, but we should only do it + // for events that went through APZ (which should be all of them). + MOZ_ASSERT(aEvent.mFlags.mHandledByAPZ); + + // If the first touchstart event was preventDefaulted, ensure that any + // subsequent additional touchstart events also get preventDefaulted. This + // ensures that e.g. pinch zooming is prevented even if just the first + // touchstart was prevented by content. + if (mTouchCounter.GetActiveTouchCount() == 0) { + mFirstTouchCancelled = isTouchPrevented; + } else { + if (mFirstTouchCancelled && !isTouchPrevented) { + APZES_LOG( + "Propagating prevent-default from first-touch for block %" PRIu64 + "\n", + aInputBlockId); + } + isTouchPrevented |= mFirstTouchCancelled; + } + + mTouchStartPrevented = isTouchPrevented; + if (isTouchPrevented) { + mContentReceivedInputBlockCallback(aInputBlockId, isTouchPrevented); + } else { + APZES_LOG("Event not prevented; pending response for %" PRIu64 " %s\n", + aInputBlockId, ToString(aGuid).c_str()); + mPendingTouchPreventedResponse = true; + mPendingTouchPreventedGuid = aGuid; + mPendingTouchPreventedBlockId = aInputBlockId; + } + break; + } + + case eTouchEnd: + if (isTouchPrevented) { + mTouchEndCancelled = true; + mEndTouchIsClick = false; + } + [[fallthrough]]; + case eTouchCancel: + mActiveElementManager->HandleTouchEndEvent(mEndTouchIsClick); + [[fallthrough]]; + case eTouchMove: { + if (!mReceivedNonTouchStart) { + // In the case where `touchstart` was preventDefaulted, + // pointercancel event should NOT be fired. + mayNeedPointerCancelEvent = !isTouchPrevented && !mTouchStartPrevented; + mReceivedNonTouchStart = true; + } + + if (mPendingTouchPreventedResponse) { + MOZ_ASSERT(aGuid == mPendingTouchPreventedGuid); + if (aEvent.mMessage == eTouchCancel) { + // If we received a touch-cancel and we were waiting for the + // first touch-move to send a content response, make the content + // response be preventDefault=true. This is the safer choice + // because content might have prevented the first touch-move, + // and even though the touch-cancel means any subsequent touch-moves + // will not be processed, the content response still influences + // the InputResult sent to GeckoView. + isTouchPrevented = true; + } + mContentReceivedInputBlockCallback(aInputBlockId, isTouchPrevented); + mPendingTouchPreventedResponse = false; + } + break; + } + + default: + MOZ_ASSERT_UNREACHABLE("Unknown touch event type"); + break; + } + + mTouchCounter.Update(aEvent); + if (mTouchCounter.GetActiveTouchCount() == 0) { + mFirstTouchCancelled = false; + } + + APZES_LOG("Pointercancel if %d %d %d %d\n", mayNeedPointerCancelEvent, + !isTouchPrevented, aApzResponse == nsEventStatus_eConsumeDoDefault, + MainThreadAgreesEventsAreConsumableByAPZ()); + // From https://w3c.github.io/pointerevents/#the-pointercancel-event; + // The user agent MUST fire a pointer event named pointercancel when it + // detects a scenario to suppress a pointer event stream. + // + // And "suppress a pointer event steam" is defined in + // https://w3c.github.io/pointerevents/#suppressing-a-pointer-event-stream . + // + // There are four scenarios when the user agent fires a pointercancel event in + // the spec. Below code corresponds to one of the scenarios (the third bullet + // point); + // The pointer is subsequently used by the user agent to manipulate the page + // viewport (e.g. panning or zooming). + if (mayNeedPointerCancelEvent && + aApzResponse == nsEventStatus_eConsumeDoDefault && + MainThreadAgreesEventsAreConsumableByAPZ()) { + WidgetTouchEvent cancelEvent(aEvent); + cancelEvent.mMessage = eTouchPointerCancel; + cancelEvent.mFlags.mCancelable = false; // mMessage != eTouchCancel; + for (uint32_t i = 0; i < cancelEvent.mTouches.Length(); ++i) { + if (mozilla::dom::Touch* touch = cancelEvent.mTouches[i]) { + touch->convertToPointer = true; + } + } + nsEventStatus status; + cancelEvent.mWidget->DispatchEvent(&cancelEvent, status); + } +} + +bool APZEventState::MainThreadAgreesEventsAreConsumableByAPZ() const { + // APZ errs on the side of saying it can consume touch events to perform + // default user-agent behaviours. In particular it may say this if it hasn't + // received accurate touch-action information. Here we double-check using + // accurate touch-action information. This code is kinda-sorta the main + // thread equivalent of AsyncPanZoomController::ArePointerEventsConsumable(). + + switch (mTouchBlockAllowedBehaviors.Length()) { + case 0: + // If we don't have any touch-action (e.g. because it is disabled) then + // APZ has no restrictions. + return true; + + case 1: { + // If there's one touch point in this touch block, then check the pan-x + // and pan-y flags. If neither is allowed, then we disagree with APZ and + // say that it can't do anything with this touch block. Note that it would + // be even better if we could check the allowed scroll directions of the + // scrollframe at this point and refine this further. + TouchBehaviorFlags flags = mTouchBlockAllowedBehaviors[0]; + return (flags & AllowedTouchBehavior::HORIZONTAL_PAN) || + (flags & AllowedTouchBehavior::VERTICAL_PAN); + } + + case 2: { + // If there's two touch points in this touch block, check that they both + // allow zooming. + for (const auto& allowed : mTouchBlockAllowedBehaviors) { + if (!(allowed & AllowedTouchBehavior::PINCH_ZOOM)) { + return false; + } + } + return true; + } + + default: + // More than two touch points? APZ shouldn't be doing anything with this, + // so APZ shouldn't be consuming them. + return false; + } +} + +void APZEventState::ProcessWheelEvent(const WidgetWheelEvent& aEvent, + uint64_t aInputBlockId) { + // If this event starts a swipe, indicate that it shouldn't result in a + // scroll by setting defaultPrevented to true. + bool defaultPrevented = aEvent.DefaultPrevented() || aEvent.TriggersSwipe(); + mContentReceivedInputBlockCallback(aInputBlockId, defaultPrevented); +} + +void APZEventState::ProcessMouseEvent(const WidgetMouseEvent& aEvent, + uint64_t aInputBlockId) { + bool defaultPrevented = false; + mContentReceivedInputBlockCallback(aInputBlockId, defaultPrevented); +} + +void APZEventState::ProcessAPZStateChange(ViewID aViewId, + APZStateChange aChange, int aArg, + Maybe<uint64_t> aInputBlockId) { + switch (aChange) { + case APZStateChange::eTransformBegin: { + nsIScrollableFrame* sf = nsLayoutUtils::FindScrollableFrameFor(aViewId); + if (sf) { + sf->SetTransformingByAPZ(true); + sf->ScrollbarActivityStarted(); + } + + nsIContent* content = nsLayoutUtils::FindContentFor(aViewId); + dom::Document* doc = content ? content->GetComposedDoc() : nullptr; + nsCOMPtr<nsIDocShell> docshell(doc ? doc->GetDocShell() : nullptr); + if (docshell && sf) { + nsDocShell* nsdocshell = static_cast<nsDocShell*>(docshell.get()); + nsdocshell->NotifyAsyncPanZoomStarted(); + } + break; + } + case APZStateChange::eTransformEnd: { + nsIScrollableFrame* sf = nsLayoutUtils::FindScrollableFrameFor(aViewId); + if (sf) { + sf->SetTransformingByAPZ(false); + sf->ScrollbarActivityStopped(); + } + + nsIContent* content = nsLayoutUtils::FindContentFor(aViewId); + dom::Document* doc = content ? content->GetComposedDoc() : nullptr; + nsCOMPtr<nsIDocShell> docshell(doc ? doc->GetDocShell() : nullptr); + if (docshell && sf) { + nsDocShell* nsdocshell = static_cast<nsDocShell*>(docshell.get()); + nsdocshell->NotifyAsyncPanZoomStopped(); + } + break; + } + case APZStateChange::eStartTouch: { + bool canBePan = aArg; + mActiveElementManager->HandleTouchStart(canBePan); + // If this is a non-scrollable content, set a timer for the amount of + // time specified by ui.touch_activation.duration_ms to clear the + // active element state. + APZES_LOG("%s: can-be-pan=%d", __FUNCTION__, aArg); + if (!canBePan) { + MOZ_ASSERT(aInputBlockId.isSome()); + } + break; + } + case APZStateChange::eStartPanning: { + // The user started to pan, so we don't want anything to be :active. + mActiveElementManager->ClearActivation(); + break; + } + case APZStateChange::eEndTouch: { + mEndTouchIsClick = aArg; + mActiveElementManager->HandleTouchEnd(); + break; + } + } +} + +void APZEventState::Destroy() { mActiveElementManager->Destroy(); } + +void APZEventState::SendPendingTouchPreventedResponse(bool aPreventDefault) { + if (mPendingTouchPreventedResponse) { + APZES_LOG("Sending response %d for pending guid: %s block id: %" PRIu64 + "\n", + aPreventDefault, ToString(mPendingTouchPreventedGuid).c_str(), + mPendingTouchPreventedBlockId); + mContentReceivedInputBlockCallback(mPendingTouchPreventedBlockId, + aPreventDefault); + mPendingTouchPreventedResponse = false; + } +} + +already_AddRefed<nsIWidget> APZEventState::GetWidget() const { + nsCOMPtr<nsIWidget> result = do_QueryReferent(mWidget); + return result.forget(); +} + +already_AddRefed<nsIContent> APZEventState::GetTouchRollup() const { + nsCOMPtr<nsIContent> result = do_QueryReferent(mTouchRollup); + return result.forget(); +} + +} // namespace layers +} // namespace mozilla |