зеркало из https://github.com/mozilla/gecko-dev.git
136 строки
5.2 KiB
C++
136 строки
5.2 KiB
C++
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
|
|
/* ***** BEGIN LICENSE BLOCK *****
|
|
* Version: NPL 1.1/GPL 2.0/LGPL 2.1
|
|
*
|
|
* The contents of this file are subject to the Netscape 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/NPL/
|
|
*
|
|
* 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
|
|
* Boris Zbarsky <bzbarsky@mit.edu>.
|
|
* Portions created by the Initial Developer are Copyright (C) 2002
|
|
* the Initial Developer. All Rights Reserved.
|
|
*
|
|
* Contributor(s):
|
|
*
|
|
* Alternatively, the contents of this file may be used under the terms of
|
|
* either 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 NPL, 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 NPL, the GPL or the LGPL.
|
|
*
|
|
* ***** END LICENSE BLOCK ***** */
|
|
|
|
#ifndef nsLayoutUtils_h__
|
|
#define nsLayoutUtils_h__
|
|
|
|
class nsIFrame;
|
|
class nsIPresContext;
|
|
class nsIContent;
|
|
class nsIAtom;
|
|
|
|
#include "prtypes.h"
|
|
#include "nsStyleContext.h"
|
|
#include "nsAutoPtr.h"
|
|
|
|
/**
|
|
* nsLayoutUtils is a namespace class used for various helper
|
|
* functions that are useful in multiple places in layout. The goal
|
|
* is not to define multiple copies of the same static helper.
|
|
*/
|
|
class nsLayoutUtils
|
|
{
|
|
public:
|
|
/**
|
|
* GetBeforeFrame returns the :before frame of the given frame, if
|
|
* one exists. This is typically O(1). The frame passed in must be
|
|
* the first-in-flow.
|
|
*
|
|
* @param aFrame the frame whose :before is wanted
|
|
* @param aPresContext the prescontext
|
|
* @return the :before frame or nsnull if there isn't one
|
|
*/
|
|
static nsIFrame* GetBeforeFrame(nsIFrame* aFrame, nsIPresContext* aPresContext);
|
|
|
|
/**
|
|
* GetAfterFrame returns the :after frame of the given frame, if one
|
|
* exists. This will walk the in-flow chain to the last-in-flow if
|
|
* needed. This function is typically O(N) in the number of child
|
|
* frames, following in-flows, etc.
|
|
*
|
|
* @param aFrame the frame whose :after is wanted
|
|
* @param aPresContext the prescontext
|
|
* @return the :after frame or nsnull if there isn't one
|
|
*/
|
|
static nsIFrame* GetAfterFrame(nsIFrame* aFrame, nsIPresContext* aPresContext);
|
|
|
|
/**
|
|
* Given a frame, search up the frame tree until we find an
|
|
* ancestor "Page" frame, if any.
|
|
*
|
|
* @param the frame to start at
|
|
* @return a frame of type nsLayoutAtoms::pageFrame or nsnull if no
|
|
* such ancestor exists
|
|
*/
|
|
static nsIFrame* GetPageFrame(nsIFrame* aFrame);
|
|
|
|
/**
|
|
* IsGeneratedContentFor returns PR_TRUE if aFrame is generated
|
|
* content of type aPseudoElement for aContent
|
|
*
|
|
* @param aContent the content node we're looking at. If this is
|
|
* null, then we just assume that aFrame has the right content
|
|
* pointer.
|
|
* @param aFrame the frame we're looking at
|
|
* @param aPseudoElement the pseudo type we're interested in
|
|
* @return whether aFrame is the generated aPseudoElement frame for aContent
|
|
*/
|
|
static PRBool IsGeneratedContentFor(nsIContent* aContent, nsIFrame* aFrame,
|
|
nsIAtom* aPseudoElement);
|
|
|
|
/**
|
|
* HasPseudoStyle returns PR_TRUE if aContent (whose primary style
|
|
* context is aStyleContext) has the aPseudoElement pseudo-style
|
|
* attached to it; returns PR_FALSE otherwise.
|
|
*
|
|
* @param aContent the content node we're looking at
|
|
* @param aStyleContext aContent's style context
|
|
* @param aPseudoElement the name of the pseudo style we care about
|
|
* @param aPresContext the presentation context
|
|
* @return whether aContent has aPseudoElement style attached to it
|
|
*/
|
|
static PRBool HasPseudoStyle(nsIContent* aContent,
|
|
nsStyleContext* aStyleContext,
|
|
nsIAtom* aPseudoElement,
|
|
nsIPresContext* aPresContext)
|
|
{
|
|
NS_PRECONDITION(aPresContext, "Must have a prescontext");
|
|
NS_PRECONDITION(aPseudoElement, "Must have a pseudo name");
|
|
|
|
nsRefPtr<nsStyleContext> pseudoContext;
|
|
if (aContent) {
|
|
pseudoContext = aPresContext->ProbePseudoStyleContextFor(aContent,
|
|
aPseudoElement,
|
|
aStyleContext);
|
|
}
|
|
return pseudoContext != nsnull;
|
|
}
|
|
|
|
};
|
|
|
|
#endif // nsLayoutUtils_h__
|