gecko-dev/dom/events/AsyncEventDispatcher.h

108 lines
3.1 KiB
C++

/* -*- 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_AsyncEventDispatcher_h_
#define mozilla_AsyncEventDispatcher_h_
#include "mozilla/Attributes.h"
#include "nsCOMPtr.h"
#include "nsIDocument.h"
#include "nsIDOMEvent.h"
#include "nsString.h"
#include "nsThreadUtils.h"
class nsINode;
namespace mozilla {
/**
* Use AsyncEventDispatcher to fire a DOM event that requires safe a stable DOM.
* For example, you may need to fire an event from within layout, but
* want to ensure that the event handler doesn't mutate the DOM at
* the wrong time, in order to avoid resulting instability.
*/
class AsyncEventDispatcher : public CancelableRunnable
{
public:
/**
* If aOnlyChromeDispatch is true, the event is dispatched to only
* chrome node. In that case, if aTarget is already a chrome node,
* the event is dispatched to it, otherwise the dispatch path starts
* at the first chrome ancestor of that target.
*/
AsyncEventDispatcher(nsINode* aTarget, const nsAString& aEventType,
bool aBubbles, bool aOnlyChromeDispatch)
: mTarget(aTarget)
, mEventType(aEventType)
, mBubbles(aBubbles)
, mOnlyChromeDispatch(aOnlyChromeDispatch)
{
}
AsyncEventDispatcher(dom::EventTarget* aTarget, const nsAString& aEventType,
bool aBubbles)
: mTarget(aTarget)
, mEventType(aEventType)
, mBubbles(aBubbles)
{
}
AsyncEventDispatcher(dom::EventTarget* aTarget, nsIDOMEvent* aEvent)
: mTarget(aTarget)
, mEvent(aEvent)
{
}
AsyncEventDispatcher(dom::EventTarget* aTarget, WidgetEvent& aEvent);
NS_IMETHOD Run() override;
nsresult Cancel() override;
nsresult PostDOMEvent();
void RunDOMEventWhenSafe();
nsCOMPtr<dom::EventTarget> mTarget;
nsCOMPtr<nsIDOMEvent> mEvent;
nsString mEventType;
bool mBubbles = false;
bool mOnlyChromeDispatch = false;
bool mCanceled = false;
};
class LoadBlockingAsyncEventDispatcher final : public AsyncEventDispatcher
{
public:
LoadBlockingAsyncEventDispatcher(nsINode* aEventNode,
const nsAString& aEventType,
bool aBubbles, bool aDispatchChromeOnly)
: AsyncEventDispatcher(aEventNode, aEventType,
aBubbles, aDispatchChromeOnly)
, mBlockedDoc(aEventNode->OwnerDoc())
{
if (mBlockedDoc) {
mBlockedDoc->BlockOnload();
}
}
LoadBlockingAsyncEventDispatcher(nsINode* aEventNode, nsIDOMEvent* aEvent)
: AsyncEventDispatcher(aEventNode, aEvent)
, mBlockedDoc(aEventNode->OwnerDoc())
{
if (mBlockedDoc) {
mBlockedDoc->BlockOnload();
}
}
~LoadBlockingAsyncEventDispatcher();
private:
nsCOMPtr<nsIDocument> mBlockedDoc;
};
} // namespace mozilla
#endif // mozilla_AsyncEventDispatcher_h_