EventDispatcher.cpp [plain text]
#include "config.h"
#include "EventDispatcher.h"
#include "EventContext.h"
#include "EventNames.h"
#include "EventPath.h"
#include "FrameView.h"
#include "HTMLInputElement.h"
#include "MouseEvent.h"
#include "NoEventDispatchAssertion.h"
#include "PseudoElement.h"
#include "ScopedEventQueue.h"
#include "ShadowRoot.h"
#include "TouchEvent.h"
#include <wtf/NeverDestroyed.h>
namespace WebCore {
class WindowEventContext {
public:
WindowEventContext(Node*, const EventContext*);
DOMWindow* window() const { return m_window.get(); }
EventTarget* target() const { return m_target.get(); }
bool handleLocalEvents(Event&);
private:
RefPtr<DOMWindow> m_window;
RefPtr<EventTarget> m_target;
};
WindowEventContext::WindowEventContext(Node* node, const EventContext* topEventContext)
{
Node* topLevelContainer = topEventContext ? topEventContext->node() : node;
if (!is<Document>(*topLevelContainer))
return;
m_window = downcast<Document>(*topLevelContainer).domWindow();
m_target = topEventContext ? topEventContext->target() : node;
}
bool WindowEventContext::handleLocalEvents(Event& event)
{
if (!m_window)
return false;
event.setTarget(m_target.copyRef());
event.setCurrentTarget(m_window.get());
m_window->fireEventListeners(event);
return true;
}
void EventDispatcher::dispatchScopedEvent(Node& node, Event& event)
{
event.setTarget(EventPath::eventTargetRespectingTargetRules(node));
ScopedEventQueue::singleton().enqueueEvent(event);
}
static void callDefaultEventHandlersInTheBubblingOrder(Event& event, const EventPath& path)
{
if (path.isEmpty())
return;
path.contextAt(0).node()->defaultEventHandler(&event);
ASSERT(!event.defaultPrevented());
if (event.defaultHandled() || !event.bubbles())
return;
size_t size = path.size();
for (size_t i = 1; i < size; ++i) {
path.contextAt(i).node()->defaultEventHandler(&event);
ASSERT(!event.defaultPrevented());
if (event.defaultHandled())
return;
}
}
static void dispatchEventInDOM(Event& event, const EventPath& path, WindowEventContext& windowEventContext)
{
event.setEventPhase(Event::CAPTURING_PHASE);
bool shouldFireEventAtWindow = event.type() != eventNames().loadEvent;
if (shouldFireEventAtWindow && windowEventContext.handleLocalEvents(event) && event.propagationStopped())
return;
for (size_t i = path.size() - 1; i > 0; --i) {
const EventContext& eventContext = path.contextAt(i);
if (eventContext.currentTargetSameAsTarget())
continue;
eventContext.handleLocalEvents(event);
if (event.propagationStopped())
return;
}
event.setEventPhase(Event::AT_TARGET);
path.contextAt(0).handleLocalEvents(event);
if (event.propagationStopped())
return;
size_t size = path.size();
for (size_t i = 1; i < size; ++i) {
const EventContext& eventContext = path.contextAt(i);
if (eventContext.currentTargetSameAsTarget())
event.setEventPhase(Event::AT_TARGET);
else if (event.bubbles() && !event.cancelBubble())
event.setEventPhase(Event::BUBBLING_PHASE);
else
continue;
eventContext.handleLocalEvents(event);
if (event.propagationStopped())
return;
}
if (event.bubbles() && !event.cancelBubble()) {
event.setEventPhase(Event::BUBBLING_PHASE);
if (shouldFireEventAtWindow)
windowEventContext.handleLocalEvents(event);
}
}
bool EventDispatcher::dispatchEvent(Node* origin, Event& event)
{
ASSERT_WITH_SECURITY_IMPLICATION(!NoEventDispatchAssertion::isEventDispatchForbidden());
ASSERT(origin);
RefPtr<Node> node(origin);
RefPtr<FrameView> view = node->document().view();
EventPath eventPath(*node, event);
if (EventTarget* relatedTarget = event.relatedTarget())
eventPath.setRelatedTarget(*node, *relatedTarget);
#if ENABLE(TOUCH_EVENTS)
if (is<TouchEvent>(event))
eventPath.retargetTouchLists(downcast<TouchEvent>(event));
#endif
ChildNodesLazySnapshot::takeChildNodesLazySnapshot();
EventTarget* target = EventPath::eventTargetRespectingTargetRules(*node);
event.setTarget(target);
if (!event.target())
return true;
ASSERT_WITH_SECURITY_IMPLICATION(!NoEventDispatchAssertion::isEventDispatchForbidden());
WindowEventContext windowEventContext(node.get(), eventPath.lastContextIfExists());
InputElementClickState clickHandlingState;
if (is<HTMLInputElement>(*node))
downcast<HTMLInputElement>(*node).willDispatchEvent(event, clickHandlingState);
if (!event.propagationStopped() && !eventPath.isEmpty()) {
event.setEventPath(eventPath);
dispatchEventInDOM(event, eventPath, windowEventContext);
event.clearEventPath();
}
event.setTarget(EventPath::eventTargetRespectingTargetRules(*node));
event.setCurrentTarget(nullptr);
event.setEventPhase(0);
if (clickHandlingState.stateful)
downcast<HTMLInputElement>(*node).didDispatchClickEvent(event, clickHandlingState);
if (!event.defaultPrevented() && !event.defaultHandled())
callDefaultEventHandlersInTheBubblingOrder(event, eventPath);
event.setTarget(windowEventContext.target());
event.setCurrentTarget(nullptr);
return !event.defaultPrevented();
}
}