layout/mathml/nsMathMLmrowFrame.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #ifndef nsMathMLmrowFrame_h___
   7 #define nsMathMLmrowFrame_h___
   8
   9 #include "mozilla/Attributes.h"
  10 #include "nsMathMLContainerFrame.h"
  11
  12 //
  13 // <mrow> -- horizontally group any number of subexpressions
  14 // <mphantom> -- make content invisible but preserve its size
  15 // <mstyle> -- make style changes that affect the rendering of its contents
  16 //
  17
  18 class nsMathMLmrowFrame : public nsMathMLContainerFrame {
  19 public:
  20   NS_DECL_FRAMEARENA_HELPERS
  21
  22   friend nsIFrame* NS_NewMathMLmrowFrame(nsIPresShell* aPresShell, nsStyleContext* aContext);
  23
  24   virtual nsresult
  25   AttributeChanged(int32_t  aNameSpaceID,
  26                    nsIAtom* aAttribute,
  27                    int32_t  aModType) override;
  28
  29   NS_IMETHOD
  30   InheritAutomaticData(nsIFrame* aParent) override;
  31
  32   NS_IMETHOD
  33   TransmitAutomaticData() override {
  34     return TransmitAutomaticDataForMrowLikeElement();
  35   }
  36
  37   virtual eMathMLFrameType
  38   GetMathMLFrameType() override;
  39
  40   bool
  41   IsMrowLike() override {
  42     // <mrow> elements with a single child are treated identically to the case
  43     // where the child wasn't within an mrow, so we pretend the mrow isn't an
  44     // mrow in that situation.
  45     return mFrames.FirstChild() != mFrames.LastChild() ||
  46            !mFrames.FirstChild();
  47   }
  48
  49 protected:
  50   explicit nsMathMLmrowFrame(nsStyleContext* aContext) : nsMathMLContainerFrame(aContext) {}
  51   virtual ~nsMathMLmrowFrame();
  52 };
  53
  54 #endif /* nsMathMLmrowFrame_h___ */