gecko-dev/content/base/public/Element.h

210 lines
7.4 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim: sw=2 ts=2 et :
* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is mozilla.org code.
*
* The Initial Developer of the Original Code is
* Mozilla Foundation.
* Portions created by the Initial Developer are Copyright (C) 2009
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Boris Zbarsky <bzbarsky@mit.edu> (Original Author)
*
* Alternatively, the contents of this file may be used under the terms of
* either of the GNU General Public License Version 2 or later (the "GPL"),
* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#ifndef mozilla_dom_Element_h__
#define mozilla_dom_Element_h__
#include "nsIContent.h"
#include "nsEventStates.h"
#include "nsDOMMemoryReporter.h"
class nsEventStateManager;
class nsGlobalWindow;
class nsFocusManager;
// Element-specific flags
enum {
// Set if the element has a pending style change.
ELEMENT_HAS_PENDING_RESTYLE = (1 << NODE_TYPE_SPECIFIC_BITS_OFFSET),
// Set if the element is a potential restyle root (that is, has a style
// change pending _and_ that style change will attempt to restyle
// descendants).
ELEMENT_IS_POTENTIAL_RESTYLE_ROOT =
(1 << (NODE_TYPE_SPECIFIC_BITS_OFFSET + 1)),
// Set if the element has a pending animation style change.
ELEMENT_HAS_PENDING_ANIMATION_RESTYLE =
(1 << (NODE_TYPE_SPECIFIC_BITS_OFFSET + 2)),
// Set if the element is a potential animation restyle root (that is,
// has an animation style change pending _and_ that style change
// will attempt to restyle descendants).
ELEMENT_IS_POTENTIAL_ANIMATION_RESTYLE_ROOT =
(1 << (NODE_TYPE_SPECIFIC_BITS_OFFSET + 3)),
// All of those bits together, for convenience.
ELEMENT_ALL_RESTYLE_FLAGS = ELEMENT_HAS_PENDING_RESTYLE |
ELEMENT_IS_POTENTIAL_RESTYLE_ROOT |
ELEMENT_HAS_PENDING_ANIMATION_RESTYLE |
ELEMENT_IS_POTENTIAL_ANIMATION_RESTYLE_ROOT,
// Just the HAS_PENDING bits, for convenience
ELEMENT_PENDING_RESTYLE_FLAGS = ELEMENT_HAS_PENDING_RESTYLE |
ELEMENT_HAS_PENDING_ANIMATION_RESTYLE,
// Remaining bits are for subclasses
ELEMENT_TYPE_SPECIFIC_BITS_OFFSET = NODE_TYPE_SPECIFIC_BITS_OFFSET + 4
};
namespace mozilla {
namespace dom {
class Link;
class Element : public nsIContent
{
public:
#ifdef MOZILLA_INTERNAL_API
Element(already_AddRefed<nsINodeInfo> aNodeInfo) :
nsIContent(aNodeInfo),
mState(NS_EVENT_STATE_MOZ_READONLY)
{}
#endif // MOZILLA_INTERNAL_API
NS_DECL_AND_IMPL_DOM_MEMORY_REPORTER_SIZEOF(Element, nsIContent)
/**
* Method to get the full state of this element. See nsEventStates.h for
* the possible bits that could be set here.
*/
nsEventStates State() const {
// mState is maintained by having whoever might have changed it
// call UpdateState() or one of the other mState mutators.
return mState;
}
/**
* Request an update of the link state for this element. This will
* make sure that if the element is a link at all then either
* NS_EVENT_STATE_VISITED or NS_EVENT_STATE_UNVISITED is set in
* mState, and a history lookup kicked off if needed to find out
* whether the link is really visited. This method will NOT send any
* state change notifications. If you want them to happen for this
* call, you need to handle them yourself.
*/
virtual void RequestLinkStateUpdate();
/**
* Ask this element to update its state. If aNotify is false, then
* state change notifications will not be dispatched; in that
* situation it is the caller's responsibility to dispatch them.
*
* In general, aNotify should only be false if we're guaranteed that
* the element can't have a frame no matter what its style is
* (e.g. if we're in the middle of adding it to the document or
* removing it from the document).
*/
void UpdateState(bool aNotify);
protected:
/**
* Method to get the _intrinsic_ content state of this element. This is the
* state that is independent of the element's presentation. To get the full
* content state, use State(). See nsEventStates.h for
* the possible bits that could be set here.
*/
virtual nsEventStates IntrinsicState() const;
/**
* Method to update mState with link state information. This does not notify.
*/
void UpdateLinkState(nsEventStates aState);
/**
* Method to add state bits. This should be called from subclass
* constructors to set up our event state correctly at construction
* time and other places where we don't want to notify a state
* change.
*/
void AddStatesSilently(nsEventStates aStates) {
mState |= aStates;
}
/**
* Method to remove state bits. This should be called from subclass
* constructors to set up our event state correctly at construction
* time and other places where we don't want to notify a state
* change.
*/
void RemoveStatesSilently(nsEventStates aStates) {
mState &= ~aStates;
}
private:
// Need to allow the ESM, nsGlobalWindow, and the focus manager to
// set our state
friend class ::nsEventStateManager;
friend class ::nsGlobalWindow;
friend class ::nsFocusManager;
// Also need to allow Link to call UpdateLinkState.
friend class Link;
void NotifyStateChange(nsEventStates aStates);
// Methods for the ESM to manage state bits. These will handle
// setting up script blockers when they notify, so no need to do it
// in the callers unless desired.
void AddStates(nsEventStates aStates) {
NS_PRECONDITION(!aStates.HasAtLeastOneOfStates(INTRINSIC_STATES),
"Should only be adding ESM-managed states here");
AddStatesSilently(aStates);
NotifyStateChange(aStates);
}
void RemoveStates(nsEventStates aStates) {
NS_PRECONDITION(!aStates.HasAtLeastOneOfStates(INTRINSIC_STATES),
"Should only be removing ESM-managed states here");
RemoveStatesSilently(aStates);
NotifyStateChange(aStates);
}
nsEventStates mState;
};
} // namespace dom
} // namespace mozilla
inline mozilla::dom::Element* nsINode::AsElement() {
NS_ASSERTION(IsElement(), "Not an element?");
return static_cast<mozilla::dom::Element*>(this);
}
#endif // mozilla_dom_Element_h__