Source code
Revision control
Copy as Markdown
Other Tools
/* -*- 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
#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/APZUtils.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),
mEndTouchState(apz::SingleTapState::NotClick),
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.
// 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.sys.mjs) 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;
mEndTouchState = apz::SingleTapState::NotClick;
}
[[fallthrough]];
case eTouchCancel:
if (mActiveElementManager->HandleTouchEndEvent(mEndTouchState)) {
mEndTouchState = apz::SingleTapState::NotClick;
}
[[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());
// 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
//
// 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 canBePanOrZoom = aArg;
mActiveElementManager->HandleTouchStart(canBePanOrZoom);
// 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-or-zoom=%d", __FUNCTION__, aArg);
if (!canBePanOrZoom) {
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: {
mEndTouchState = static_cast<apz::SingleTapState>(aArg);
if (mActiveElementManager->HandleTouchEnd(mEndTouchState)) {
mEndTouchState = apz::SingleTapState::NotClick;
}
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