layout/mathml/nsMathMLmsqrtFrame.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 nsMathMLmsqrtFrame_h___
   7 #define nsMathMLmsqrtFrame_h___
   8
   9 #include "mozilla/Attributes.h"
  10 #include "nsMathMLmencloseFrame.h"
  11
  12 //
  13 // <msqrt> -- form a radical
  14 //
  15
  16 /*
  17 The MathML REC describes:
  18
  19 The <msqrt> element is used to display square roots.
  20 The syntax for <msqrt> is:
  21   <msqrt> base </msqrt>
  22
  23 Attributes of <msqrt> and <mroot>:
  24
  25 None (except the attributes allowed for all MathML elements, listed in Section
  26 2.3.4).
  27
  28 The <mroot> element increments scriptlevel by 2, and sets displaystyle to
  29 "false", within index, but leaves both attributes unchanged within base. The
  30 <msqrt> element leaves both attributes unchanged within all its arguments.
  31 These attributes are inherited by every element from its rendering environment,
  32 but can be set explicitly only on <mstyle>. (See Section 3.3.4.)
  33 */
  34
  35 class nsMathMLmsqrtFrame : public nsMathMLmencloseFrame {
  36 public:
  37   NS_DECL_FRAMEARENA_HELPERS
  38
  39   friend nsIFrame* NS_NewMathMLmsqrtFrame(nsIPresShell*   aPresShell,
  40                                           nsStyleContext* aContext);
  41
  42   virtual void
  43   Init(nsIContent*       aContent,
  44        nsContainerFrame* aParent,
  45        nsIFrame*         aPrevInFlow) override;
  46
  47   NS_IMETHOD
  48   InheritAutomaticData(nsIFrame* aParent) override;
  49
  50   virtual nsresult
  51   AttributeChanged(int32_t         aNameSpaceID,
  52                    nsIAtom*        aAttribute,
  53                    int32_t         aModType) override;
  54
  55   virtual bool
  56   IsMrowLike() override
  57   {
  58     return mFrames.FirstChild() != mFrames.LastChild() ||
  59            !mFrames.FirstChild();
  60   }
  61
  62 protected:
  63   explicit nsMathMLmsqrtFrame(nsStyleContext* aContext);
  64   virtual ~nsMathMLmsqrtFrame();
  65 };
  66
  67 #endif /* nsMathMLmsqrtFrame_h___ */
  68