gecko-dev/dom/base/mozAutoDocUpdate.h

56 строки
1.6 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 mozAutoDocUpdate_h_
#define mozAutoDocUpdate_h_
#include "nsContentUtils.h" // For AddScriptBlocker() and RemoveScriptBlocker().
#include "nsIDocument.h"
#include "nsIDocumentObserver.h"
/**
* Helper class to automatically handle batching of document updates. This
* class will call BeginUpdate on construction and EndUpdate on destruction on
* the given document with the given update type. The document could be null,
* in which case no updates will be called. The constructor also takes a
* boolean that can be set to false to prevent notifications.
*/
class MOZ_STACK_CLASS mozAutoDocUpdate
{
public:
mozAutoDocUpdate(nsIDocument* aDocument, bool aNotify)
: mDocument(aNotify ? aDocument : nullptr)
{
if (mDocument) {
mDocument->BeginUpdate();
} else {
nsContentUtils::AddScriptBlocker();
}
}
~mozAutoDocUpdate()
{
if (mDocument) {
mDocument->EndUpdate();
} else {
nsContentUtils::RemoveScriptBlocker();
}
}
private:
nsCOMPtr<nsIDocument> mDocument;
};
#define MOZ_AUTO_DOC_UPDATE_PASTE2(tok,line) tok##line
#define MOZ_AUTO_DOC_UPDATE_PASTE(tok,line) \
MOZ_AUTO_DOC_UPDATE_PASTE2(tok,line)
#define MOZ_AUTO_DOC_UPDATE(doc,notify) \
mozAutoDocUpdate MOZ_AUTO_DOC_UPDATE_PASTE(_autoDocUpdater_, __LINE__) \
(doc,notify)
#endif