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