gecko-dev/dom/events/DOMEventTargetHelper.h

228 строки
8.0 KiB
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/* -*- 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/. */
#ifndef mozilla_DOMEventTargetHelper_h_
#define mozilla_DOMEventTargetHelper_h_
#include "nsCOMPtr.h"
#include "nsGkAtoms.h"
#include "nsCycleCollectionParticipant.h"
#include "nsPIDOMWindow.h"
#include "nsIScriptGlobalObject.h"
#include "nsIScriptContext.h"
#include "MainThreadUtils.h"
#include "mozilla/Attributes.h"
#include "mozilla/EventListenerManager.h"
#include "mozilla/LinkedList.h"
#include "mozilla/dom/EventTarget.h"
namespace mozilla {
class ErrorResult;
namespace dom {
class Document;
class Event;
} // namespace dom
#define NS_DOMEVENTTARGETHELPER_IID \
{ \
0xa28385c6, 0x9451, 0x4d7e, { \
0xa3, 0xdd, 0xf4, 0xb6, 0x87, 0x2f, 0xa4, 0x76 \
} \
}
class DOMEventTargetHelper : public dom::EventTarget,
public LinkedListElement<DOMEventTargetHelper> {
public:
DOMEventTargetHelper()
: mParentObject(nullptr),
mOwnerWindow(nullptr),
mHasOrHasHadOwnerWindow(false),
mIsKeptAlive(false) {}
explicit DOMEventTargetHelper(nsPIDOMWindowInner* aWindow)
: mParentObject(nullptr),
mOwnerWindow(nullptr),
mHasOrHasHadOwnerWindow(false),
mIsKeptAlive(false) {
// Be careful not to call the virtual BindToOwner() in a
// constructor.
nsIGlobalObject* global = aWindow ? aWindow->AsGlobal() : nullptr;
BindToOwnerInternal(global);
}
explicit DOMEventTargetHelper(nsIGlobalObject* aGlobalObject)
: mParentObject(nullptr),
mOwnerWindow(nullptr),
mHasOrHasHadOwnerWindow(false),
mIsKeptAlive(false) {
// Be careful not to call the virtual BindToOwner() in a
// constructor.
BindToOwnerInternal(aGlobalObject);
}
explicit DOMEventTargetHelper(DOMEventTargetHelper* aOther)
: mParentObject(nullptr),
mOwnerWindow(nullptr),
mHasOrHasHadOwnerWindow(false),
mIsKeptAlive(false) {
// Be careful not to call the virtual BindToOwner() in a
// constructor.
if (!aOther) {
BindToOwnerInternal(static_cast<nsIGlobalObject*>(nullptr));
return;
}
BindToOwnerInternal(aOther->GetParentObject());
mHasOrHasHadOwnerWindow = aOther->HasOrHasHadOwner();
}
NS_DECL_CYCLE_COLLECTING_ISUPPORTS
NS_DECL_CYCLE_COLLECTION_SKIPPABLE_SCRIPT_HOLDER_CLASS(DOMEventTargetHelper)
virtual EventListenerManager* GetExistingListenerManager() const override;
virtual EventListenerManager* GetOrCreateListenerManager() override;
bool ComputeDefaultWantsUntrusted(ErrorResult& aRv) override;
using EventTarget::DispatchEvent;
bool DispatchEvent(dom::Event& aEvent, dom::CallerType aCallerType,
ErrorResult& aRv) override;
void GetEventTargetParent(EventChainPreVisitor& aVisitor) override;
nsresult PostHandleEvent(EventChainPostVisitor& aVisitor) override;
NS_DECLARE_STATIC_IID_ACCESSOR(NS_DOMEVENTTARGETHELPER_IID)
void GetParentObject(nsIScriptGlobalObject** aParentObject) {
if (mParentObject) {
CallQueryInterface(mParentObject, aParentObject);
} else {
*aParentObject = nullptr;
}
}
static DOMEventTargetHelper* FromSupports(nsISupports* aSupports) {
dom::EventTarget* target = static_cast<dom::EventTarget*>(aSupports);
#ifdef DEBUG
{
nsCOMPtr<dom::EventTarget> target_qi = do_QueryInterface(aSupports);
// If this assertion fires the QI implementation for the object in
// question doesn't use the EventTarget pointer as the
// nsISupports pointer. That must be fixed, or we'll crash...
NS_ASSERTION(target_qi == target, "Uh, fix QI!");
}
#endif
return static_cast<DOMEventTargetHelper*>(target);
}
bool HasListenersFor(const nsAString& aType) const {
return mListenerManager && mListenerManager->HasListenersFor(aType);
}
bool HasListenersFor(nsAtom* aTypeWithOn) const {
return mListenerManager && mListenerManager->HasListenersFor(aTypeWithOn);
}
virtual nsPIDOMWindowOuter* GetOwnerGlobalForBindingsInternal() override {
return nsPIDOMWindowOuter::GetFromCurrentInner(GetOwner());
}
nsresult CheckCurrentGlobalCorrectness() const;
nsPIDOMWindowInner* GetOwner() const { return mOwnerWindow; }
// Like GetOwner, but only returns non-null if the window being returned is
// current (in the "current document" sense of the HTML spec).
nsPIDOMWindowInner* GetWindowIfCurrent() const;
// Returns the document associated with this event target, if that document is
// the current document of its browsing context. Will return null otherwise.
mozilla::dom::Document* GetDocumentIfCurrent() const;
// DETH subclasses may override the BindToOwner(nsIGlobalObject*) method
// to take action when dynamically binding to a new global. This is only
// called on rebind since virtual methods cannot be called from the
// constructor. The other BindToOwner() methods will call into this
// method.
//
// NOTE: Any overrides of BindToOwner() *must* invoke
// DOMEventTargetHelper::BindToOwner(aOwner).
virtual void BindToOwner(nsIGlobalObject* aOwner);
void BindToOwner(nsPIDOMWindowInner* aOwner);
void BindToOwner(DOMEventTargetHelper* aOther);
virtual void DisconnectFromOwner();
using EventTarget::GetParentObject;
nsIGlobalObject* GetOwnerGlobal() const final { return mParentObject; }
bool HasOrHasHadOwner() { return mHasOrHasHadOwnerWindow; }
virtual void EventListenerAdded(nsAtom* aType) override;
virtual void EventListenerRemoved(nsAtom* aType) override;
// Dispatch a trusted, non-cancellable and non-bubbling event to |this|.
nsresult DispatchTrustedEvent(const nsAString& aEventName);
protected:
virtual ~DOMEventTargetHelper();
nsresult WantsUntrusted(bool* aRetVal);
void MaybeUpdateKeepAlive();
void MaybeDontKeepAlive();
// If this method returns true your object is kept alive until it returns
// false. You can use this method instead using
// NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_BEGIN macro.
virtual bool IsCertainlyAliveForCC() const { return mIsKeptAlive; }
RefPtr<EventListenerManager> mListenerManager;
// Make |event| trusted and dispatch |aEvent| to |this|.
nsresult DispatchTrustedEvent(dom::Event* aEvent);
virtual void LastRelease() {}
void KeepAliveIfHasListenersFor(const nsAString& aType);
void KeepAliveIfHasListenersFor(nsAtom* aType);
void IgnoreKeepAliveIfHasListenersFor(const nsAString& aType);
void IgnoreKeepAliveIfHasListenersFor(nsAtom* aType);
void BindToOwnerInternal(nsIGlobalObject* aOwner);
private:
// The parent global object. The global will clear this when
// it is destroyed by calling DisconnectFromOwner().
nsIGlobalObject* MOZ_NON_OWNING_REF mParentObject;
// mParentObject pre QI-ed and cached (inner window)
// (it is needed for off main thread access)
// It is obtained in BindToOwner and reset in DisconnectFromOwner.
nsPIDOMWindowInner* MOZ_NON_OWNING_REF mOwnerWindow;
bool mHasOrHasHadOwnerWindow;
struct {
nsTArray<nsString> mStrings;
nsTArray<RefPtr<nsAtom>> mAtoms;
} mKeepingAliveTypes;
bool mIsKeptAlive;
};
NS_DEFINE_STATIC_IID_ACCESSOR(DOMEventTargetHelper, NS_DOMEVENTTARGETHELPER_IID)
} // namespace mozilla
// WebIDL event handlers
#define IMPL_EVENT_HANDLER(_event) \
inline mozilla::dom::EventHandlerNonNull* GetOn##_event() { \
return GetEventHandler(nsGkAtoms::on##_event); \
} \
inline void SetOn##_event(mozilla::dom::EventHandlerNonNull* aCallback) { \
SetEventHandler(nsGkAtoms::on##_event, aCallback); \
}
#endif // mozilla_DOMEventTargetHelper_h_