layout/mathml/base/src/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 "nsPresContext.h"
  44 #include "nsStyleContext.h"
  45 #include "nsStyleConsts.h"
  46 #include "nsINameSpaceManager.h"
  47 #include "nsIRenderingContext.h"
  48 #include "nsIFontMetrics.h"
  49
  50 #include "nsMathMLmstyleFrame.h"
  51
  52 //
  53 // <mstyle> -- style change
  54 //
  55
  56 nsIFrame*
  57 NS_NewMathMLmstyleFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)
  58 {
  59   return new (aPresShell) nsMathMLmstyleFrame(aContext);
  60 }
  61
  62 nsMathMLmstyleFrame::~nsMathMLmstyleFrame()
  63 {
  64 }
  65
  66 // mstyle needs special care for its scriptlevel and displaystyle attributes
  67 NS_IMETHODIMP
  68 nsMathMLmstyleFrame::InheritAutomaticData(nsIFrame* aParent)
  69 {
  70   // let the base class get the default from our parent
  71   nsMathMLContainerFrame::InheritAutomaticData(aParent);
  72
  73   // sync with our current state
  74   mPresentationData.flags |= NS_MATHML_STRETCH_ALL_CHILDREN_VERTICALLY;
  75   mPresentationData.mstyle = this;
  76
  77   // see if the displaystyle attribute is there
  78   nsMathMLFrame::FindAttrDisplaystyle(mContent, mPresentationData);
  79
  80   return NS_OK;
  81 }
  82
  83 NS_IMETHODIMP
  84 nsMathMLmstyleFrame::TransmitAutomaticData()
  85 {
  86   // Nothing particular to do here, the values that we computed in
  87   // InheritAutomaticData() are the values that we wanted to pass to
  88   // our children. Our children would have inherited these values in
  89   // their own InheritAutomaticData() as we descended the frame tree.
  90
  91   return NS_OK;
  92 }
  93
  94 // displaystyle and scriptlevel are special in <mstyle>...
  95 // Since UpdatePresentation() and UpdatePresentationDataFromChildAt() can be called
  96 // by a parent, ensure that the explicit attributes of <mstyle> take precedence
  97 NS_IMETHODIMP
  98 nsMathMLmstyleFrame::UpdatePresentationData(PRUint32        aFlagsValues,
  99                                             PRUint32        aWhichFlags)
 100 {
 101   if (NS_MATHML_HAS_EXPLICIT_DISPLAYSTYLE(mPresentationData.flags)) {
 102     // our current state takes precedence, disallow updating the displastyle
 103     aWhichFlags &= ~NS_MATHML_DISPLAYSTYLE;
 104     aFlagsValues &= ~NS_MATHML_DISPLAYSTYLE;
 105   }
 106
 107   return nsMathMLContainerFrame::UpdatePresentationData(aFlagsValues, aWhichFlags);
 108 }
 109
 110 NS_IMETHODIMP
 111 nsMathMLmstyleFrame::UpdatePresentationDataFromChildAt(PRInt32         aFirstIndex,
 112                                                        PRInt32         aLastIndex,
 113                                                        PRUint32        aFlagsValues,
 114                                                        PRUint32        aWhichFlags)
 115 {
 116   if (NS_MATHML_HAS_EXPLICIT_DISPLAYSTYLE(mPresentationData.flags)) {
 117     // our current state takes precedence, disallow updating the displastyle
 118     aWhichFlags &= ~NS_MATHML_DISPLAYSTYLE;
 119     aFlagsValues &= ~NS_MATHML_DISPLAYSTYLE;
 120   }
 121
 122   // let the base class worry about the update
 123   return
 124     nsMathMLContainerFrame::UpdatePresentationDataFromChildAt(
 125       aFirstIndex, aLastIndex, aFlagsValues, aWhichFlags);
 126 }
 127
 128 NS_IMETHODIMP
 129 nsMathMLmstyleFrame::AttributeChanged(PRInt32         aNameSpaceID,
 130                                       nsIAtom*        aAttribute,
 131                                       PRInt32         aModType)
 132 {
 133   // Other attributes can affect too many things, ask our parent to re-layout
 134   // its children so that we can pick up changes in our attributes & transmit
 135   // them in our subtree. However, our siblings will be re-laid too. We used
 136   // to have a more speedier but more verbose alternative that didn't re-layout
 137   // our siblings. See bug 114909 - attachment 67668.
 138   return ReLayoutChildren(mParent, NS_FRAME_IS_DIRTY);
 139 }