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chromium / chromium / src / 8ed45293563fb49186ca5bd97734353337921de4 / . / third_party / blink / renderer / core / input / mouse_event_manager.cc
blob: db5b1bfc1ca819d415fedcaabf7067a8ed28b98a [file] [log] [blame]
// Copyright 2016 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "third_party/blink/renderer/core/input/mouse_event_manager.h"
#include "build/build_config.h"
#include "third_party/blink/public/platform/task_type.h"
#include "third_party/blink/renderer/core/clipboard/data_object.h"
#include "third_party/blink/renderer/core/clipboard/data_transfer.h"
#include "third_party/blink/renderer/core/clipboard/data_transfer_access_policy.h"
#include "third_party/blink/renderer/core/dom/element.h"
#include "third_party/blink/renderer/core/dom/element_traversal.h"
#include "third_party/blink/renderer/core/editing/editing_utilities.h"
#include "third_party/blink/renderer/core/editing/ephemeral_range.h"
#include "third_party/blink/renderer/core/editing/frame_selection.h"
#include "third_party/blink/renderer/core/editing/selection_controller.h"
#include "third_party/blink/renderer/core/editing/visible_selection.h"
#include "third_party/blink/renderer/core/events/drag_event.h"
#include "third_party/blink/renderer/core/events/mouse_event.h"
#include "third_party/blink/renderer/core/events/web_input_event_conversion.h"
#include "third_party/blink/renderer/core/frame/local_dom_window.h"
#include "third_party/blink/renderer/core/frame/local_frame.h"
#include "third_party/blink/renderer/core/frame/local_frame_view.h"
#include "third_party/blink/renderer/core/frame/settings.h"
#include "third_party/blink/renderer/core/html/canvas/html_canvas_element.h"
#include "third_party/blink/renderer/core/input/event_handler.h"
#include "third_party/blink/renderer/core/input/event_handling_util.h"
#include "third_party/blink/renderer/core/input/input_device_capabilities.h"
#include "third_party/blink/renderer/core/input/keyboard_event_manager.h"
#include "third_party/blink/renderer/core/layout/hit_test_result.h"
#include "third_party/blink/renderer/core/layout/layout_view.h"
#include "third_party/blink/renderer/core/page/autoscroll_controller.h"
#include "third_party/blink/renderer/core/page/drag_controller.h"
#include "third_party/blink/renderer/core/page/drag_state.h"
#include "third_party/blink/renderer/core/page/focus_controller.h"
#include "third_party/blink/renderer/core/paint/paint_layer.h"
#include "third_party/blink/renderer/core/paint/paint_layer_scrollable_area.h"
#include "third_party/blink/renderer/core/svg/svg_document_extensions.h"
#include "third_party/blink/renderer/platform/geometry/float_quad.h"
#include "third_party/blink/renderer/platform/histogram.h"
namespace blink {
namespace {
String CanvasRegionId(Node* node, const WebMouseEvent& mouse_event) {
if (!node->IsElementNode())
return String();
Element* element = ToElement(node);
if (!element->IsInCanvasSubtree())
return String();
HTMLCanvasElement* canvas =
Traversal<HTMLCanvasElement>::FirstAncestorOrSelf(*element);
// In this case, the event target is canvas and mouse rerouting doesn't
// happen.
if (canvas == element)
return String();
return canvas->GetIdFromControl(element);
}
// The amount of time to wait before sending a fake mouse event triggered
// during a scroll.
constexpr TimeDelta kFakeMouseMoveIntervalDuringScroll =
TimeDelta::FromMilliseconds(100);
// The amount of time to wait before sending a fake mouse event on style and
// layout changes sets to 50Hz, same as common screen refresh rate.
constexpr TimeDelta kFakeMouseMoveIntervalPerFrame =
TimeDelta::FromMilliseconds(20);
// TODO(crbug.com/653490): Read these values from the OS.
#if defined(OS_MACOSX)
const int kDragThresholdX = 3;
const int kDragThresholdY = 3;
constexpr TimeDelta kTextDragDelay = TimeDelta::FromSecondsD(0.15);
#else
const int kDragThresholdX = 4;
const int kDragThresholdY = 4;
constexpr TimeDelta kTextDragDelay = TimeDelta::FromSecondsD(0.0);
#endif
} // namespace
enum class DragInitiator { kMouse, kTouch };
MouseEventManager::MouseEventManager(LocalFrame& frame,
ScrollManager& scroll_manager)
: frame_(frame),
scroll_manager_(scroll_manager),
fake_mouse_move_event_timer_(
frame.GetTaskRunner(TaskType::kUserInteraction),
this,
&MouseEventManager::FakeMouseMoveEventTimerFired) {
Clear();
}
void MouseEventManager::Clear() {
node_under_mouse_ = nullptr;
mouse_press_node_ = nullptr;
mouse_down_may_start_autoscroll_ = false;
mouse_down_may_start_drag_ = false;
captures_dragging_ = false;
is_mouse_position_unknown_ = true;
last_known_mouse_position_ = FloatPoint();
last_known_mouse_global_position_ = FloatPoint();
mouse_pressed_ = false;
click_count_ = 0;
click_element_ = nullptr;
mouse_down_element_ = nullptr;
mouse_down_pos_ = IntPoint();
mouse_down_timestamp_ = TimeTicks();
mouse_down_ = WebMouseEvent();
svg_pan_ = false;
drag_start_pos_ = LayoutPoint();
fake_mouse_move_event_timer_.Stop();
ResetDragState();
ClearDragDataTransfer();
}
MouseEventManager::~MouseEventManager() = default;
void MouseEventManager::Trace(blink::Visitor* visitor) {
visitor->Trace(frame_);
visitor->Trace(scroll_manager_);
visitor->Trace(node_under_mouse_);
visitor->Trace(mouse_press_node_);
visitor->Trace(click_element_);
visitor->Trace(mouse_down_element_);
SynchronousMutationObserver::Trace(visitor);
}
MouseEventManager::MouseEventBoundaryEventDispatcher::
MouseEventBoundaryEventDispatcher(MouseEventManager* mouse_event_manager,
const WebMouseEvent* web_mouse_event,
EventTarget* exited_target,
const String& canvas_region_id)
: mouse_event_manager_(mouse_event_manager),
web_mouse_event_(web_mouse_event),
exited_target_(exited_target),
canvas_region_id_(canvas_region_id) {}
void MouseEventManager::MouseEventBoundaryEventDispatcher::DispatchOut(
EventTarget* target,
EventTarget* related_target) {
Dispatch(target, related_target, EventTypeNames::mouseout,
CanvasRegionId(exited_target_->ToNode(), *web_mouse_event_),
*web_mouse_event_, false);
}
void MouseEventManager::MouseEventBoundaryEventDispatcher::DispatchOver(
EventTarget* target,
EventTarget* related_target) {
Dispatch(target, related_target, EventTypeNames::mouseover, canvas_region_id_,
*web_mouse_event_, false);
}
void MouseEventManager::MouseEventBoundaryEventDispatcher::DispatchLeave(
EventTarget* target,
EventTarget* related_target,
bool check_for_listener) {
Dispatch(target, related_target, EventTypeNames::mouseleave,
CanvasRegionId(exited_target_->ToNode(), *web_mouse_event_),
*web_mouse_event_, check_for_listener);
}
void MouseEventManager::MouseEventBoundaryEventDispatcher::DispatchEnter(
EventTarget* target,
EventTarget* related_target,
bool check_for_listener) {
Dispatch(target, related_target, EventTypeNames::mouseenter,
canvas_region_id_, *web_mouse_event_, check_for_listener);
}
AtomicString
MouseEventManager::MouseEventBoundaryEventDispatcher::GetLeaveEvent() {
return EventTypeNames::mouseleave;
}
AtomicString
MouseEventManager::MouseEventBoundaryEventDispatcher::GetEnterEvent() {
return EventTypeNames::mouseenter;
}
void MouseEventManager::MouseEventBoundaryEventDispatcher::Dispatch(
EventTarget* target,
EventTarget* related_target,
const AtomicString& type,
const String& canvas_region_id,
const WebMouseEvent& web_mouse_event,
bool check_for_listener) {
mouse_event_manager_->DispatchMouseEvent(target, type, web_mouse_event,
canvas_region_id, related_target,
check_for_listener);
}
void MouseEventManager::SendBoundaryEvents(EventTarget* exited_target,
EventTarget* entered_target,
const String& canvas_region_id,
const WebMouseEvent& mouse_event) {
MouseEventBoundaryEventDispatcher boundary_event_dispatcher(
this, &mouse_event, exited_target, canvas_region_id);
boundary_event_dispatcher.SendBoundaryEvents(exited_target, entered_target);
}
WebInputEventResult MouseEventManager::DispatchMouseEvent(
EventTarget* target,
const AtomicString& mouse_event_type,
const WebMouseEvent& mouse_event,
const String& canvas_region_id,
EventTarget* related_target,
bool check_for_listener) {
if (target && target->ToNode() &&
(!check_for_listener || target->HasEventListeners(mouse_event_type))) {
Node* target_node = target->ToNode();
int click_count = 0;
if (mouse_event_type == EventTypeNames::mouseup ||
mouse_event_type == EventTypeNames::mousedown ||
mouse_event_type == EventTypeNames::click ||
mouse_event_type == EventTypeNames::auxclick ||
mouse_event_type == EventTypeNames::dblclick) {
click_count = click_count_;
}
bool is_mouse_enter_or_leave =
mouse_event_type == EventTypeNames::mouseenter ||
mouse_event_type == EventTypeNames::mouseleave;
MouseEventInit initializer;
initializer.setBubbles(!is_mouse_enter_or_leave);
initializer.setCancelable(!is_mouse_enter_or_leave);
MouseEvent::SetCoordinatesFromWebPointerProperties(
mouse_event.FlattenTransform(), target_node->GetDocument().domWindow(),
initializer);
initializer.setButton(static_cast<short>(mouse_event.button));
initializer.setButtons(MouseEvent::WebInputEventModifiersToButtons(
mouse_event.GetModifiers()));
initializer.setView(target_node->GetDocument().domWindow());
initializer.setComposed(true);
initializer.setDetail(click_count);
initializer.setRegion(canvas_region_id);
initializer.setRelatedTarget(related_target);
UIEventWithKeyState::SetFromWebInputEventModifiers(
initializer,
static_cast<WebInputEvent::Modifiers>(mouse_event.GetModifiers()));
initializer.setSourceCapabilities(
target_node->GetDocument().domWindow()
? target_node->GetDocument()
.domWindow()
->GetInputDeviceCapabilities()
->FiresTouchEvents(mouse_event.FromTouch())
: nullptr);
MouseEvent* event = MouseEvent::Create(
mouse_event_type, initializer, mouse_event.TimeStamp(),
mouse_event.FromTouch() ? MouseEvent::kFromTouch
: MouseEvent::kRealOrIndistinguishable,
mouse_event.menu_source_type);
DispatchEventResult dispatch_result = target->DispatchEvent(*event);
return EventHandlingUtil::ToWebInputEventResult(dispatch_result);
}
return WebInputEventResult::kNotHandled;
}
WebInputEventResult MouseEventManager::SetMousePositionAndDispatchMouseEvent(
Node* target_node,
const String& canvas_region_id,
const AtomicString& event_type,
const WebMouseEvent& web_mouse_event) {
// If the target node is a text node, dispatch on the parent node.
if (target_node && target_node->IsTextNode())
target_node = FlatTreeTraversal::Parent(*target_node);
SetNodeUnderMouse(target_node, canvas_region_id, web_mouse_event);
return DispatchMouseEvent(node_under_mouse_, event_type, web_mouse_event,
canvas_region_id, nullptr);
}
WebInputEventResult MouseEventManager::DispatchMouseClickIfNeeded(
const MouseEventWithHitTestResults& mev,
Element& mouse_release_target) {
// We only prevent click event when the click may cause contextmenu to popup.
// However, we always send auxclick.
bool context_menu_event = false;
#if defined(OS_MACOSX)
// FIXME: The Mac port achieves the same behavior by checking whether the
// context menu is currently open in WebPage::mouseEvent(). Consider merging
// the implementations.
if (mev.Event().button == WebPointerProperties::Button::kLeft &&
mev.Event().GetModifiers() & WebInputEvent::Modifiers::kControlKey)
context_menu_event = true;
#endif
const bool should_dispatch_click_event =
click_count_ > 0 && !context_menu_event && mouse_down_element_ &&
mouse_release_target.CanParticipateInFlatTree() &&
mouse_down_element_->CanParticipateInFlatTree() &&
mouse_down_element_->isConnected() &&
!(frame_->GetEventHandler()
.GetSelectionController()
.HasExtendedSelection() &&
IsLinkSelection(mev));
if (!should_dispatch_click_event)
return WebInputEventResult::kNotHandled;
Node* click_target_node = nullptr;
if (mouse_down_element_ == mouse_release_target) {
click_target_node = mouse_down_element_;
} else if (mouse_down_element_->GetDocument() ==
mouse_release_target.GetDocument()) {
// Updates distribution because a 'mouseup' event listener can make the
// tree dirty at dispatchMouseEvent() invocation above.
// Unless distribution is updated, commonAncestor would hit ASSERT.
mouse_down_element_->UpdateDistributionForFlatTreeTraversal();
mouse_release_target.UpdateDistributionForFlatTreeTraversal();
click_target_node = mouse_release_target.CommonAncestor(
*mouse_down_element_, EventHandlingUtil::ParentForClickEvent);
}
if (!click_target_node)
return WebInputEventResult::kNotHandled;
DEFINE_STATIC_LOCAL(BooleanHistogram, histogram,
("Event.ClickNotFiredDueToDomManipulation"));
if (click_element_ && click_element_->CanParticipateInFlatTree() &&
click_element_->isConnected()) {
DCHECK(click_element_ == mouse_down_element_);
histogram.Count(false);
} else {
histogram.Count(true);
}
if ((click_element_ && click_element_->CanParticipateInFlatTree() &&
click_element_->isConnected()) ||
RuntimeEnabledFeatures::ClickRetargettingEnabled()) {
return DispatchMouseEvent(
click_target_node,
(mev.Event().button == WebPointerProperties::Button::kLeft)
? EventTypeNames::click
: EventTypeNames::auxclick,
mev.Event(), mev.CanvasRegionId(), nullptr);
}
return WebInputEventResult::kNotHandled;
}
void MouseEventManager::FakeMouseMoveEventTimerFired(TimerBase* timer) {
TRACE_EVENT0("input", "MouseEventManager::fakeMouseMoveEventTimerFired");
DCHECK(timer == &fake_mouse_move_event_timer_);
if (is_mouse_position_unknown_)
return;
LocalFrameView* view = frame_->View();
if (!view)
return;
if (!frame_->GetPage() || !frame_->GetPage()->GetFocusController().IsActive())
return;
// Don't dispatch a synthetic mouse move event if the mouse cursor is not
// visible to the user.
if (!frame_->GetPage()->IsCursorVisible())
return;
WebPointerEvent::Button button = WebPointerProperties::Button::kNoButton;
int modifiers = KeyboardEventManager::GetCurrentModifierState() |
WebInputEvent::kRelativeMotionEvent;
if (mouse_pressed_) {
button = WebPointerProperties::Button::kLeft;
modifiers |= WebInputEvent::kLeftButtonDown;
}
WebMouseEvent fake_mouse_move_event(WebInputEvent::kMouseMove,
last_known_mouse_position_,
last_known_mouse_global_position_, button,
0, modifiers, CurrentTimeTicks());
Vector<WebMouseEvent> coalesced_events;
frame_->GetEventHandler().HandleMouseMoveEvent(
TransformWebMouseEvent(view, fake_mouse_move_event), coalesced_events);
}
void MouseEventManager::CancelFakeMouseMoveEvent() {
fake_mouse_move_event_timer_.Stop();
}
void MouseEventManager::SetNodeUnderMouse(
Node* target,
const String& canvas_region_id,
const WebMouseEvent& web_mouse_event) {
Node* last_node_under_mouse = node_under_mouse_;
node_under_mouse_ = target;
PaintLayer* layer_for_last_node =
EventHandlingUtil::LayerForNode(last_node_under_mouse);
PaintLayer* layer_for_node_under_mouse =
EventHandlingUtil::LayerForNode(node_under_mouse_.Get());
Page* page = frame_->GetPage();
if (page && (layer_for_last_node &&
(!layer_for_node_under_mouse ||
layer_for_node_under_mouse != layer_for_last_node))) {
// The mouse has moved between layers.
if (ScrollableArea* scrollable_area_for_last_node =
EventHandlingUtil::AssociatedScrollableArea(layer_for_last_node))
scrollable_area_for_last_node->MouseExitedContentArea();
}
if (page && (layer_for_node_under_mouse &&
(!layer_for_last_node ||
layer_for_node_under_mouse != layer_for_last_node))) {
// The mouse has moved between layers.
if (ScrollableArea* scrollable_area_for_node_under_mouse =
EventHandlingUtil::AssociatedScrollableArea(
layer_for_node_under_mouse))
scrollable_area_for_node_under_mouse->MouseEnteredContentArea();
}
if (last_node_under_mouse &&
last_node_under_mouse->GetDocument() != frame_->GetDocument()) {
last_node_under_mouse = nullptr;
}
SendBoundaryEvents(last_node_under_mouse, node_under_mouse_, canvas_region_id,
web_mouse_event);
}
void MouseEventManager::NodeChildrenWillBeRemoved(ContainerNode& container) {
if (container == click_element_)
return;
if (!container.IsShadowIncludingInclusiveAncestorOf(click_element_.Get()))
return;
click_element_ = nullptr;
// TODO(crbug.com/716694): Do not reset mouse_down_element_ for the purpose of
// gathering data.
}
void MouseEventManager::NodeWillBeRemoved(Node& node_to_be_removed) {
if (node_to_be_removed.IsShadowIncludingInclusiveAncestorOf(
click_element_.Get())) {
// We don't dispatch click events if the mousedown node is removed
// before a mouseup event. It is compatible with IE and Firefox.
click_element_ = nullptr;
// TODO(crbug.com/716694): Do not reset mouse_down_element_ for the purpose
// of gathering data.
}
}
Node* MouseEventManager::GetNodeUnderMouse() {
return node_under_mouse_;
}
WebInputEventResult MouseEventManager::HandleMouseFocus(
const HitTestResult& hit_test_result,
InputDeviceCapabilities* source_capabilities) {
// If clicking on a frame scrollbar, do not mess up with content focus.
if (auto* layout_view = frame_->ContentLayoutObject()) {
if (hit_test_result.GetScrollbar() && frame_->ContentLayoutObject()) {
if (hit_test_result.GetScrollbar()->GetScrollableArea() ==
layout_view->GetScrollableArea())
return WebInputEventResult::kNotHandled;
}
}
// The layout needs to be up to date to determine if an element is focusable.
frame_->GetDocument()->UpdateStyleAndLayoutIgnorePendingStylesheets();
Element* element = nullptr;
if (node_under_mouse_) {
element = node_under_mouse_->IsElementNode()
? ToElement(node_under_mouse_)
: node_under_mouse_->ParentOrShadowHostElement();
}
for (; element; element = element->ParentOrShadowHostElement()) {
if (element->IsFocusable() && element->IsFocusedElementInDocument())
return WebInputEventResult::kNotHandled;
if (element->IsMouseFocusable())
break;
}
DCHECK(!element || element->IsMouseFocusable());
// To fix <rdar://problem/4895428> Can't drag selected ToDo, we don't focus
// a node on mouse down if it's selected and inside a focused node. It will
// be focused if the user does a mouseup over it, however, because the
// mouseup will set a selection inside it, which will call
// FrameSelection::setFocusedNodeIfNeeded.
// TODO(editing-dev): The use of VisibleSelection should be audited. See
// crbug.com/657237 for details.
if (element &&
frame_->Selection().ComputeVisibleSelectionInDOMTree().IsRange()) {
const EphemeralRange& range = frame_->Selection()
.ComputeVisibleSelectionInDOMTree()
.ToNormalizedEphemeralRange();
if (IsNodeFullyContained(range, *element) &&
element->IsDescendantOf(frame_->GetDocument()->FocusedElement()))
return WebInputEventResult::kNotHandled;
}
// Only change the focus when clicking scrollbars if it can transfered to a
// mouse focusable node.
if (!element && hit_test_result.GetScrollbar())
return WebInputEventResult::kHandledSystem;
if (Page* page = frame_->GetPage()) {
// If focus shift is blocked, we eat the event. Note we should never
// clear swallowEvent if the page already set it (e.g., by canceling
// default behavior).
if (element) {
if (SlideFocusOnShadowHostIfNecessary(*element))
return WebInputEventResult::kHandledSystem;
if (!page->GetFocusController().SetFocusedElement(
element, frame_,
FocusParams(SelectionBehaviorOnFocus::kNone, kWebFocusTypeMouse,
source_capabilities)))
return WebInputEventResult::kHandledSystem;
} else {
// We call setFocusedElement even with !element in order to blur
// current focus element when a link is clicked; this is expected by
// some sites that rely on onChange handlers running from form
// fields before the button click is processed.
if (!page->GetFocusController().SetFocusedElement(
nullptr, frame_,
FocusParams(SelectionBehaviorOnFocus::kNone, kWebFocusTypeNone,
source_capabilities)))
return WebInputEventResult::kHandledSystem;
}
}
return WebInputEventResult::kNotHandled;
}
bool MouseEventManager::SlideFocusOnShadowHostIfNecessary(
const Element& element) {
if (element.AuthorShadowRoot() &&
element.AuthorShadowRoot()->delegatesFocus()) {
Document* doc = frame_->GetDocument();
if (element.IsShadowIncludingInclusiveAncestorOf(doc->FocusedElement())) {
// If the inner element is already focused, do nothing.
return true;
}
// If the host has a focusable inner element, focus it. Otherwise, the host
// takes focus.
Page* page = frame_->GetPage();
DCHECK(page);
Element* found =
page->GetFocusController().FindFocusableElementInShadowHost(element);
if (found && element.IsShadowIncludingInclusiveAncestorOf(found)) {
// Use WebFocusTypeForward instead of WebFocusTypeMouse here to mean the
// focus has slided.
found->focus(FocusParams(SelectionBehaviorOnFocus::kReset,
kWebFocusTypeForward, nullptr));
return true;
}
}
return false;
}
void MouseEventManager::HandleMouseReleaseEventUpdateStates() {
ClearDragHeuristicState();
InvalidateClick();
frame_->GetEventHandler().GetSelectionController().SetMouseDownMayStartSelect(
false);
}
void MouseEventManager::HandleMousePressEventUpdateStates(
const WebMouseEvent& mouse_event) {
CancelFakeMouseMoveEvent();
mouse_pressed_ = true;
captures_dragging_ = true;
SetLastKnownMousePosition(mouse_event);
mouse_down_may_start_drag_ = false;
mouse_down_may_start_autoscroll_ = false;
mouse_down_timestamp_ = mouse_event.TimeStamp();
if (LocalFrameView* view = frame_->View()) {
mouse_down_pos_ = view->ConvertFromRootFrame(
FlooredIntPoint(mouse_event.PositionInRootFrame()));
} else {
InvalidateClick();
}
frame_->GetEventHandler().GetSelectionController().SetMouseDownMayStartSelect(
false);
}
bool MouseEventManager::IsMousePositionUnknown() {
return is_mouse_position_unknown_;
}
IntPoint MouseEventManager::LastKnownMousePosition() {
return FlooredIntPoint(last_known_mouse_position_);
}
FloatPoint MouseEventManager::LastKnownMousePositionGlobal() {
return last_known_mouse_global_position_;
}
void MouseEventManager::SetLastKnownMousePosition(const WebMouseEvent& event) {
is_mouse_position_unknown_ = event.GetType() == WebInputEvent::kMouseLeave;
last_known_mouse_position_ = event.PositionInWidget();
last_known_mouse_global_position_ = event.PositionInScreen();
}
void MouseEventManager::SetLastMousePositionAsUnknown() {
is_mouse_position_unknown_ = true;
}
void MouseEventManager::DispatchFakeMouseMoveEventSoon(
MouseEventManager::FakeMouseMoveReason fake_mouse_move_reason) {
if (fake_mouse_move_reason ==
MouseEventManager::FakeMouseMoveReason::kDuringScroll &&
mouse_pressed_)
return;
// TODO(lanwei): When the mouse position is unknown, we do not send the fake
// mousemove event for now, so we cannot update the hover states and mouse
// cursor. We should keep the last mouse position somewhere in browser.
// Please see crbug.com/307375, crbug.com/714378.
if (is_mouse_position_unknown_)
return;
// Reschedule the timer, to prevent dispatching mouse move events
// during a scroll. This avoids a potential source of scroll jank.
// Or dispatch a fake mouse move to update hover states when the layout
// changes.
TimeDelta interval =
fake_mouse_move_reason ==
MouseEventManager::FakeMouseMoveReason::kDuringScroll
? kFakeMouseMoveIntervalDuringScroll
: kFakeMouseMoveIntervalPerFrame;
fake_mouse_move_event_timer_.StartOneShot(interval, FROM_HERE);
}
void MouseEventManager::DispatchFakeMouseMoveEventSoonInQuad(
const FloatQuad& quad) {
LocalFrameView* view = frame_->View();
if (!view)
return;
if (!quad.ContainsPoint(view->ViewportToFrame(last_known_mouse_position_)))
return;
DispatchFakeMouseMoveEventSoon(
MouseEventManager::FakeMouseMoveReason::kDuringScroll);
}
WebInputEventResult MouseEventManager::HandleMousePressEvent(
const MouseEventWithHitTestResults& event) {
TRACE_EVENT0("blink", "MouseEventManager::handleMousePressEvent");
ResetDragState();
CancelFakeMouseMoveEvent();
frame_->GetDocument()->UpdateStyleAndLayoutIgnorePendingStylesheets();
bool single_click = event.Event().click_count <= 1;
mouse_down_may_start_drag_ =
single_click && !IsLinkSelection(event) && !IsExtendingSelection(event);
mouse_down_ = event.Event();
if (frame_->GetDocument()->IsSVGDocument() &&
frame_->GetDocument()->AccessSVGExtensions().ZoomAndPanEnabled()) {
if ((event.Event().GetModifiers() & WebInputEvent::Modifiers::kShiftKey) &&
single_click) {
svg_pan_ = true;
frame_->GetDocument()->AccessSVGExtensions().StartPan(
frame_->View()->ConvertFromRootFrame(FloatPoint(
FlooredIntPoint(event.Event().PositionInRootFrame()))));
return WebInputEventResult::kHandledSystem;
}
}
// We don't do this at the start of mouse down handling,
// because we don't want to do it until we know we didn't hit a widget.
if (single_click)
FocusDocumentView();
Node* inner_node = event.InnerNode();
mouse_press_node_ = inner_node;
frame_->GetDocument()->SetSequentialFocusNavigationStartingPoint(inner_node);
drag_start_pos_ = FlooredIntPoint(event.Event().PositionInRootFrame());
mouse_pressed_ = true;
bool swallow_event =
frame_->GetEventHandler().GetSelectionController().HandleMousePressEvent(
event);
mouse_down_may_start_autoscroll_ =
frame_->GetEventHandler()
.GetSelectionController()
.MouseDownMayStartSelect() ||
(mouse_press_node_ && mouse_press_node_->GetLayoutBox() &&
mouse_press_node_->GetLayoutBox()->CanBeProgramaticallyScrolled());
return swallow_event ? WebInputEventResult::kHandledSystem
: WebInputEventResult::kNotHandled;
}
WebInputEventResult MouseEventManager::HandleMouseReleaseEvent(
const MouseEventWithHitTestResults& event) {
AutoscrollController* controller = scroll_manager_->GetAutoscrollController();
if (controller && controller->SelectionAutoscrollInProgress())
scroll_manager_->StopAutoscroll();
return frame_->GetEventHandler()
.GetSelectionController()
.HandleMouseReleaseEvent(event, drag_start_pos_)
? WebInputEventResult::kHandledSystem
: WebInputEventResult::kNotHandled;
}
void MouseEventManager::UpdateSelectionForMouseDrag() {
frame_->GetEventHandler()
.GetSelectionController()
.UpdateSelectionForMouseDrag(drag_start_pos_,
LayoutPoint(last_known_mouse_position_));
}
bool MouseEventManager::HandleDragDropIfPossible(
const GestureEventWithHitTestResults& targeted_event) {
if (frame_->GetSettings() &&
frame_->GetSettings()->GetTouchDragDropEnabled() && frame_->View()) {
const WebGestureEvent& gesture_event = targeted_event.Event();
unsigned modifiers = gesture_event.GetModifiers();
// TODO(mustaq): Suppressing long-tap MouseEvents could break
// drag-drop. Will do separately because of the risk. crbug.com/606938.
WebMouseEvent mouse_down_event(
WebInputEvent::kMouseDown, gesture_event,
WebPointerProperties::Button::kLeft, 1,
modifiers | WebInputEvent::Modifiers::kLeftButtonDown |
WebInputEvent::Modifiers::kIsCompatibilityEventForTouch,
CurrentTimeTicks());
mouse_down_ = mouse_down_event;
WebMouseEvent mouse_drag_event(
WebInputEvent::kMouseMove, gesture_event,
WebPointerProperties::Button::kLeft, 1,
modifiers | WebInputEvent::Modifiers::kLeftButtonDown |
WebInputEvent::Modifiers::kIsCompatibilityEventForTouch,
CurrentTimeTicks());
HitTestRequest request(HitTestRequest::kReadOnly);
MouseEventWithHitTestResults mev =
EventHandlingUtil::PerformMouseEventHitTest(frame_, request,
mouse_drag_event);
mouse_down_may_start_drag_ = true;
ResetDragState();
mouse_down_pos_ = frame_->View()->ConvertFromRootFrame(
FlooredIntPoint(mouse_drag_event.PositionInRootFrame()));
return HandleDrag(mev, DragInitiator::kTouch);
}
return false;
}
void MouseEventManager::FocusDocumentView() {
Page* page = frame_->GetPage();
if (!page)
return;
page->GetFocusController().FocusDocumentView(frame_);
}
WebInputEventResult MouseEventManager::HandleMouseDraggedEvent(
const MouseEventWithHitTestResults& event) {
TRACE_EVENT0("blink", "MouseEventManager::handleMouseDraggedEvent");
bool is_pen = event.Event().pointer_type ==
blink::WebPointerProperties::PointerType::kPen;
WebPointerProperties::Button pen_drag_button =
WebPointerProperties::Button::kLeft;
if (frame_->GetSettings() &&
frame_->GetSettings()->GetBarrelButtonForDragEnabled())
pen_drag_button = WebPointerProperties::Button::kBarrel;
// While resetting m_mousePressed here may seem out of place, it turns out
// to be needed to handle some bugs^Wfeatures in Blink mouse event handling:
// 1. Certain elements, such as <embed>, capture mouse events. They do not
// bubble back up. One way for a <embed> to start capturing mouse events
// is on a mouse press. The problem is the <embed> node only starts
// capturing mouse events *after* m_mousePressed for the containing frame
// has already been set to true. As a result, the frame's EventHandler
// never sees the mouse release event, which is supposed to reset
// m_mousePressed... so m_mousePressed ends up remaining true until the
// event handler finally gets another mouse released event. Oops.
// 2. Dragging doesn't start until after a mouse press event, but a drag
// that ends as a result of a mouse release does not send a mouse release
// event. As a result, m_mousePressed also ends up remaining true until
// the next mouse release event seen by the EventHandler.
if ((!is_pen &&
event.Event().button != WebPointerProperties::Button::kLeft) ||
(is_pen && event.Event().button != pen_drag_button)) {
mouse_pressed_ = false;
}
// When pressing Esc key while dragging and the object is outside of the
// we get a mouse leave event here.
if (!mouse_pressed_ || event.Event().GetType() == WebInputEvent::kMouseLeave)
return WebInputEventResult::kNotHandled;
// We disable the drag and drop actions on pen input on windows.
bool should_handle_drag = true;
#if defined(OS_WIN)
should_handle_drag = !is_pen;
#endif
if (should_handle_drag && HandleDrag(event, DragInitiator::kMouse))
return WebInputEventResult::kHandledSystem;
Node* target_node = event.InnerNode();
if (!target_node)
return WebInputEventResult::kNotHandled;
LayoutObject* layout_object = target_node->GetLayoutObject();
if (!layout_object) {
Node* parent = FlatTreeTraversal::Parent(*target_node);
if (!parent)
return WebInputEventResult::kNotHandled;
layout_object = parent->GetLayoutObject();
if (!layout_object || !layout_object->IsListBox())
return WebInputEventResult::kNotHandled;
}
mouse_down_may_start_drag_ = false;
frame_->GetEventHandler().GetSelectionController().HandleMouseDraggedEvent(
event, mouse_down_pos_, drag_start_pos_,
LayoutPoint(last_known_mouse_position_));
// The call into HandleMouseDraggedEvent may have caused a re-layout,
// so get the LayoutObject again.
layout_object = target_node->GetLayoutObject();
if (layout_object && mouse_down_may_start_autoscroll_ &&
!scroll_manager_->MiddleClickAutoscrollInProgress() &&
!frame_->Selection().SelectedHTMLForClipboard().IsEmpty()) {
if (AutoscrollController* controller =
scroll_manager_->GetAutoscrollController()) {
// Avoid updating the lifecycle unless it's possible to autoscroll.
layout_object->GetFrameView()->UpdateAllLifecyclePhasesExceptPaint();
// The lifecycle update above may have invalidated the previous layout.
layout_object = target_node->GetLayoutObject();
if (layout_object) {
controller->StartAutoscrollForSelection(layout_object);
mouse_down_may_start_autoscroll_ = false;
}
}
}
return WebInputEventResult::kHandledSystem;
}
bool MouseEventManager::HandleDrag(const MouseEventWithHitTestResults& event,
DragInitiator initiator) {
DCHECK(event.Event().GetType() == WebInputEvent::kMouseMove);
// Callers must protect the reference to LocalFrameView, since this function
// may dispatch DOM events, causing page/LocalFrameView to go away.
DCHECK(frame_);
DCHECK(frame_->View());
if (!frame_->GetPage())
return false;
if (mouse_down_may_start_drag_) {
HitTestRequest request(HitTestRequest::kReadOnly);
HitTestLocation location(mouse_down_pos_);
HitTestResult result(request, location);
frame_->ContentLayoutObject()->HitTest(location, result);
Node* node = result.InnerNode();
if (node) {
DragController::SelectionDragPolicy selection_drag_policy =
event.Event().TimeStamp() - mouse_down_timestamp_ < kTextDragDelay
? DragController::kDelayedSelectionDragResolution
: DragController::kImmediateSelectionDragResolution;
GetDragState().drag_src_ =
frame_->GetPage()->GetDragController().DraggableNode(
frame_, node, mouse_down_pos_, selection_drag_policy,
GetDragState().drag_type_);
} else {
ResetDragState();
}
if (!GetDragState().drag_src_)
mouse_down_may_start_drag_ = false; // no element is draggable
}
if (!mouse_down_may_start_drag_) {
return initiator == DragInitiator::kMouse &&
!frame_->GetEventHandler()
.GetSelectionController()
.MouseDownMayStartSelect() &&
!mouse_down_may_start_autoscroll_;
}
if (initiator == DragInitiator::kMouse &&
!DragThresholdExceeded(
FlooredIntPoint(event.Event().PositionInRootFrame()))) {
ResetDragState();
return true;
}
if (!TryStartDrag(event)) {
// Something failed to start the drag, clean up.
ClearDragDataTransfer();
ResetDragState();
} else {
// Once the drag operation is initiated, we don't want to treat this
// gesture as a click.
InvalidateClick();
// Since drag operation started we need to send a pointercancel for the
// corresponding pointer.
if (initiator == DragInitiator::kMouse) {
frame_->GetEventHandler().HandlePointerEvent(
WebPointerEvent::CreatePointerCausesUaActionEvent(
WebPointerProperties::PointerType::kMouse,
event.Event().TimeStamp()),
Vector<WebPointerEvent>());
}
// TODO(crbug.com/708278): If the drag starts with touch the touch cancel
// should trigger the release of pointer capture.
}
mouse_down_may_start_drag_ = false;
// Whether or not the drag actually started, no more default handling (like
// selection).
return true;
}
DataTransfer* MouseEventManager::CreateDraggingDataTransfer() const {
return DataTransfer::Create(DataTransfer::kDragAndDrop,
DataTransferAccessPolicy::kWritable,
DataObject::Create());
}
bool MouseEventManager::TryStartDrag(
const MouseEventWithHitTestResults& event) {
// The DataTransfer would only be non-empty if we missed a dragEnd.
// Clear it anyway, just to make sure it gets numbified.
ClearDragDataTransfer();
GetDragState().drag_data_transfer_ = CreateDraggingDataTransfer();
DragController& drag_controller = frame_->GetPage()->GetDragController();
if (!drag_controller.PopulateDragDataTransfer(frame_, GetDragState(),
mouse_down_pos_))
return false;
if (DispatchDragSrcEvent(EventTypeNames::dragstart, mouse_down_) !=
WebInputEventResult::kNotHandled)
return false;
// Dispatching the event could cause |frame_| to be detached.
if (!frame_->GetPage())
return false;
// If dispatching dragstart brings about another mouse down -- one way
// this will happen is if a DevTools user breaks within a dragstart
// handler and then clicks on the suspended page -- the drag state is
// reset. Hence, need to check if this particular drag operation can
// continue even if dispatchEvent() indicates no (direct) cancellation.
// Do that by checking if m_dragSrc is still set.
if (!GetDragState().drag_src_)
return false;
// Do not start dragging in password field.
// TODO(editing-dev): The use of
// updateStyleAndLayoutIgnorePendingStylesheets needs to be audited. See
// http://crbug.com/590369 for more details.
frame_->GetDocument()->UpdateStyleAndLayoutIgnorePendingStylesheets();
if (IsInPasswordField(
frame_->Selection().ComputeVisibleSelectionInDOMTree().Start()))
return false;
// Invalidate clipboard here against anymore pasteboard writing for
// security. The drag image can still be changed as we drag, but not
// the pasteboard data.
GetDragState().drag_data_transfer_->SetAccessPolicy(
DataTransferAccessPolicy::kImageWritable);
if (drag_controller.StartDrag(frame_, GetDragState(), event.Event(),
mouse_down_pos_))
return true;
// Drag was canned at the last minute - we owe m_dragSrc a DRAGEND event
DispatchDragSrcEvent(EventTypeNames::dragend, event.Event());
return false;
}
// Returns if we should continue "default processing", i.e., whether
// eventhandler canceled.
WebInputEventResult MouseEventManager::DispatchDragSrcEvent(
const AtomicString& event_type,
const WebMouseEvent& event) {
return DispatchDragEvent(event_type, GetDragState().drag_src_.Get(), nullptr,
event, GetDragState().drag_data_transfer_.Get());
}
WebInputEventResult MouseEventManager::DispatchDragEvent(
const AtomicString& event_type,
Node* drag_target,
Node* related_target,
const WebMouseEvent& event,
DataTransfer* data_transfer) {
LocalFrameView* view = frame_->View();
// FIXME: We might want to dispatch a dragleave even if the view is gone.
if (!view)
return WebInputEventResult::kNotHandled;
// We should be setting relatedTarget correctly following the spec:
// https://html.spec.whatwg.org/multipage/interaction.html#dragevent
// At the same time this should prevent exposing a node from another document.
if (related_target &&
related_target->GetDocument() != drag_target->GetDocument())
related_target = nullptr;
DragEventInit initializer;
initializer.setBubbles(true);
initializer.setCancelable(event_type != EventTypeNames::dragleave &&
event_type != EventTypeNames::dragend);
MouseEvent::SetCoordinatesFromWebPointerProperties(
event.FlattenTransform(), frame_->GetDocument()->domWindow(),
initializer);
initializer.setButton(0);
initializer.setButtons(
MouseEvent::WebInputEventModifiersToButtons(event.GetModifiers()));
initializer.setRelatedTarget(related_target);
initializer.setView(frame_->GetDocument()->domWindow());
initializer.setComposed(true);
initializer.setGetDataTransfer(data_transfer);
initializer.setSourceCapabilities(
frame_->GetDocument()->domWindow()
? frame_->GetDocument()
->domWindow()
->GetInputDeviceCapabilities()
->FiresTouchEvents(event.FromTouch())
: nullptr);
UIEventWithKeyState::SetFromWebInputEventModifiers(
initializer, static_cast<WebInputEvent::Modifiers>(event.GetModifiers()));
DragEvent* me = DragEvent::Create(event_type, initializer, event.TimeStamp(),
event.FromTouch()
? MouseEvent::kFromTouch
: MouseEvent::kRealOrIndistinguishable);
return EventHandlingUtil::ToWebInputEventResult(
drag_target->DispatchEvent(*me));
}
void MouseEventManager::ClearDragDataTransfer() {
if (!frame_->GetPage())
return;
if (GetDragState().drag_data_transfer_) {
GetDragState().drag_data_transfer_->ClearDragImage();
GetDragState().drag_data_transfer_->SetAccessPolicy(
DataTransferAccessPolicy::kNumb);
}
}
void MouseEventManager::DragSourceEndedAt(const WebMouseEvent& event,
DragOperation operation) {
if (GetDragState().drag_src_) {
GetDragState().drag_data_transfer_->SetDestinationOperation(operation);
// The return value is ignored because dragend is not cancelable.
DispatchDragSrcEvent(EventTypeNames::dragend, event);
}
ClearDragDataTransfer();
ResetDragState();
// In case the drag was ended due to an escape key press we need to ensure
// that consecutive mousemove events don't reinitiate the drag and drop.
mouse_down_may_start_drag_ = false;
}
DragState& MouseEventManager::GetDragState() {
DCHECK(frame_->GetPage());
return frame_->GetPage()->GetDragController().GetDragState();
}
void MouseEventManager::ResetDragState() {
if (!frame_->GetPage())
return;
GetDragState().drag_src_ = nullptr;
}
bool MouseEventManager::DragThresholdExceeded(
const IntPoint& drag_location_in_root_frame) const {
LocalFrameView* view = frame_->View();
if (!view)
return false;
IntPoint drag_location =
view->ConvertFromRootFrame(drag_location_in_root_frame);
IntSize delta = drag_location - mouse_down_pos_;
// WebKit's drag thresholds depend on the type of object being dragged. If we
// want to revive that behavior, we can multiply the threshold constants with
// a number based on dragState().m_dragType.
return abs(delta.Width()) >= kDragThresholdX ||
abs(delta.Height()) >= kDragThresholdY;
}
void MouseEventManager::ClearDragHeuristicState() {
// Used to prevent mouseMoveEvent from initiating a drag before
// the mouse is pressed again.
mouse_pressed_ = false;
captures_dragging_ = false;
mouse_down_may_start_drag_ = false;
mouse_down_may_start_autoscroll_ = false;
}
bool MouseEventManager::HandleSvgPanIfNeeded(bool is_release_event) {
if (!svg_pan_)
return false;
svg_pan_ = !is_release_event;
frame_->GetDocument()->AccessSVGExtensions().UpdatePan(
frame_->View()->ViewportToFrame(last_known_mouse_position_));
return true;
}
void MouseEventManager::InvalidateClick() {
click_count_ = 0;
click_element_ = nullptr;
mouse_down_element_ = nullptr;
}
bool MouseEventManager::MousePressed() {
return mouse_pressed_;
}
void MouseEventManager::ReleaseMousePress() {
mouse_pressed_ = false;
}
bool MouseEventManager::CapturesDragging() const {
return captures_dragging_;
}
void MouseEventManager::SetCapturesDragging(bool captures_dragging) {
captures_dragging_ = captures_dragging;
}
Node* MouseEventManager::MousePressNode() {
return mouse_press_node_;
}
void MouseEventManager::SetMousePressNode(Node* node) {
mouse_press_node_ = node;
}
void MouseEventManager::SetClickElement(Element* element) {
SetContext(element ? element->ownerDocument() : nullptr);
click_element_ = element;
mouse_down_element_ = element;
}
void MouseEventManager::SetClickCount(int click_count) {
click_count_ = click_count;
}
bool MouseEventManager::MouseDownMayStartDrag() {
return mouse_down_may_start_drag_;
}
bool MouseEventManager::FakeMouseMovePending() const {
return fake_mouse_move_event_timer_.IsActive();
}
} // namespace blink