layout/generic/nsImageMap.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 /* code for HTML client-side image maps */
   7
   8 #ifndef nsImageMap_h
   9 #define nsImageMap_h
  10
  11 #include "mozilla/gfx/2D.h"
  12 #include "nsCOMPtr.h"
  13 #include "nsCoord.h"
  14 #include "nsTArray.h"
  15 #include "nsStubMutationObserver.h"
  16 #include "nsIDOMEventListener.h"
  17
  18 class Area;
  19 class nsImageFrame;
  20 class nsIFrame;
  21 class nsIContent;
  22 struct nsRect;
  23
  24 class nsImageMap MOZ_FINAL : public nsStubMutationObserver,
  25                              public nsIDOMEventListener
  26 {
  27   typedef mozilla::gfx::DrawTarget DrawTarget;
  28   typedef mozilla::gfx::ColorPattern ColorPattern;
  29   typedef mozilla::gfx::StrokeOptions StrokeOptions;
  30
  31 public:
  32   nsImageMap();
  33
  34   nsresult Init(nsImageFrame* aImageFrame, nsIContent* aMap);
  35
  36   /**
  37    * Return the first area element (in content order) for the given aX,aY pixel
  38    * coordinate or nullptr if the coordinate is outside all areas.
  39    */
  40   nsIContent* GetArea(nscoord aX, nscoord aY) const;
  41
  42   /**
  43    * Return area elements count associated with the image map.
  44    */
  45   uint32_t AreaCount() const { return mAreas.Length(); }
  46
  47   /**
  48    * Return area element at the given index.
  49    */
  50   nsIContent* GetAreaAt(uint32_t aIndex) const;
  51
  52   void Draw(nsIFrame* aFrame, DrawTarget& aDrawTarget,
  53             const ColorPattern& aColor,
  54             const StrokeOptions& aStrokeOptions = StrokeOptions());
  55
  56   /**
  57    * Called just before the nsImageFrame releases us.
  58    * Used to break the cycle caused by the DOM listener.
  59    */
  60   void Destroy();
  61
  62   // nsISupports
  63   NS_DECL_ISUPPORTS
  64
  65   // nsIMutationObserver
  66   NS_DECL_NSIMUTATIONOBSERVER_ATTRIBUTECHANGED
  67   NS_DECL_NSIMUTATIONOBSERVER_CONTENTAPPENDED
  68   NS_DECL_NSIMUTATIONOBSERVER_CONTENTINSERTED
  69   NS_DECL_NSIMUTATIONOBSERVER_CONTENTREMOVED
  70   NS_DECL_NSIMUTATIONOBSERVER_PARENTCHAINCHANGED
  71
  72   //nsIDOMEventListener
  73   NS_DECL_NSIDOMEVENTLISTENER
  74
  75   nsresult GetBoundsForAreaContent(nsIContent *aContent,
  76                                    nsRect& aBounds);
  77
  78 protected:
  79   virtual ~nsImageMap();
  80
  81   void FreeAreas();
  82
  83   nsresult UpdateAreas();
  84   nsresult SearchForAreas(nsIContent* aParent, bool& aFoundArea,
  85                           bool& aFoundAnchor);
  86
  87   nsresult AddArea(nsIContent* aArea);
  88
  89   void MaybeUpdateAreas(nsIContent *aContent);
  90
  91   nsImageFrame* mImageFrame;  // the frame that owns us
  92   nsCOMPtr<nsIContent> mMap;
  93   nsAutoTArray<Area*, 8> mAreas; // almost always has some entries
  94   bool mContainsBlockContents;
  95 };
  96
  97 #endif /* nsImageMap_h */