layout/mathml/nsMathMLmstyleFrame.cpp

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* ***** BEGIN LICENSE BLOCK *****
   3  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   4  *
   5  * The contents of this file are subject to the Mozilla Public License Version
   6  * 1.1 (the "License"); you may not use this file except in compliance with
   7  * the License. You may obtain a copy of the License at
   8  * http://www.mozilla.org/MPL/
   9  *
  10  * Software distributed under the License is distributed on an "AS IS" basis,
  11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  12  * for the specific language governing rights and limitations under the
  13  * License.
  14  *
  15  * The Original Code is Mozilla MathML Project.
  16  *
  17  * The Initial Developer of the Original Code is
  18  * The University Of Queensland.
  19  * Portions created by the Initial Developer are Copyright (C) 1999
  20  * the Initial Developer. All Rights Reserved.
  21  *
  22  * Contributor(s):
  23  *   Roger B. Sidje <rbs@maths.uq.edu.au>
  24  *   David J. Fiddes <D.J.Fiddes@hw.ac.uk>
  25  *
  26  * Alternatively, the contents of this file may be used under the terms of
  27  * either of the GNU General Public License Version 2 or later (the "GPL"),
  28  * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
  29  * in which case the provisions of the GPL or the LGPL are applicable instead
  30  * of those above. If you wish to allow use of your version of this file only
  31  * under the terms of either the GPL or the LGPL, and not to allow others to
  32  * use your version of this file under the terms of the MPL, indicate your
  33  * decision by deleting the provisions above and replace them with the notice
  34  * and other provisions required by the GPL or the LGPL. If you do not delete
  35  * the provisions above, a recipient may use your version of this file under
  36  * the terms of any one of the MPL, the GPL or the LGPL.
  37  *
  38  * ***** END LICENSE BLOCK ***** */
  39
  40
  41 #include "nsCOMPtr.h"
  42 #include "nsFrame.h"
  43 #include "nsStyleContext.h"
  44 #include "nsStyleConsts.h"
  45 #include "nsINameSpaceManager.h"
  46 #include "nsIRenderingContext.h"
  47 #include "nsIFontMetrics.h"
  48
  49 #include "nsMathMLmstyleFrame.h"
  50
  51 //
  52 // <mstyle> -- style change
  53 //
  54
  55 nsIFrame*
  56 NS_NewMathMLmstyleFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)
  57 {
  58   return new (aPresShell) nsMathMLmstyleFrame(aContext);
  59 }
  60
  61 NS_IMPL_FRAMEARENA_HELPERS(nsMathMLmstyleFrame)
  62
  63 nsMathMLmstyleFrame::~nsMathMLmstyleFrame()
  64 {
  65 }
  66
  67 // mstyle needs special care for its scriptlevel and displaystyle attributes
  68 NS_IMETHODIMP
  69 nsMathMLmstyleFrame::InheritAutomaticData(nsIFrame* aParent)
  70 {
  71   // let the base class get the default from our parent
  72   nsMathMLContainerFrame::InheritAutomaticData(aParent);
  73
  74   // sync with our current state
  75   mPresentationData.flags |= NS_MATHML_STRETCH_ALL_CHILDREN_VERTICALLY;
  76   mPresentationData.mstyle = this;
  77
  78   // see if the displaystyle attribute is there
  79   nsMathMLFrame::FindAttrDisplaystyle(mContent, mPresentationData);
  80
  81   return NS_OK;
  82 }
  83
  84 NS_IMETHODIMP
  85 nsMathMLmstyleFrame::TransmitAutomaticData()
  86 {
  87   // Nothing particular to do here, the values that we computed in
  88   // InheritAutomaticData() are the values that we wanted to pass to
  89   // our children. Our children would have inherited these values in
  90   // their own InheritAutomaticData() as we descended the frame tree.
  91
  92   return NS_OK;
  93 }
  94
  95 // displaystyle and scriptlevel are special in <mstyle>...
  96 // Since UpdatePresentation() and UpdatePresentationDataFromChildAt() can be called
  97 // by a parent, ensure that the explicit attributes of <mstyle> take precedence
  98 NS_IMETHODIMP
  99 nsMathMLmstyleFrame::UpdatePresentationData(PRUint32        aFlagsValues,
 100                                             PRUint32        aWhichFlags)
 101 {
 102   if (NS_MATHML_HAS_EXPLICIT_DISPLAYSTYLE(mPresentationData.flags)) {
 103     // our current state takes precedence, disallow updating the displastyle
 104     aWhichFlags &= ~NS_MATHML_DISPLAYSTYLE;
 105     aFlagsValues &= ~NS_MATHML_DISPLAYSTYLE;
 106   }
 107
 108   return nsMathMLContainerFrame::UpdatePresentationData(aFlagsValues, aWhichFlags);
 109 }
 110
 111 NS_IMETHODIMP
 112 nsMathMLmstyleFrame::UpdatePresentationDataFromChildAt(PRInt32         aFirstIndex,
 113                                                        PRInt32         aLastIndex,
 114                                                        PRUint32        aFlagsValues,
 115                                                        PRUint32        aWhichFlags)
 116 {
 117   if (NS_MATHML_HAS_EXPLICIT_DISPLAYSTYLE(mPresentationData.flags)) {
 118     // our current state takes precedence, disallow updating the displastyle
 119     aWhichFlags &= ~NS_MATHML_DISPLAYSTYLE;
 120     aFlagsValues &= ~NS_MATHML_DISPLAYSTYLE;
 121   }
 122
 123   // let the base class worry about the update
 124   return
 125     nsMathMLContainerFrame::UpdatePresentationDataFromChildAt(
 126       aFirstIndex, aLastIndex, aFlagsValues, aWhichFlags);
 127 }
 128
 129 NS_IMETHODIMP
 130 nsMathMLmstyleFrame::AttributeChanged(PRInt32         aNameSpaceID,
 131                                       nsIAtom*        aAttribute,
 132                                       PRInt32         aModType)
 133 {
 134   // Other attributes can affect too many things, ask our parent to re-layout
 135   // its children so that we can pick up changes in our attributes & transmit
 136   // them in our subtree. However, our siblings will be re-laid too. We used
 137   // to have a more speedier but more verbose alternative that didn't re-layout
 138   // our siblings. See bug 114909 - attachment 67668.
 139   return ReLayoutChildren(mParent);
 140 }