gecko-dev/layout/generic/nsImageMap.h

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/* code for HTML client-side image maps */

#ifndef nsImageMap_h
#define nsImageMap_h

#include "nsISupports.h"
#include "nsCoord.h"
#include "nsTArray.h"
#include "nsStubMutationObserver.h"
#include "nsIDOMEventListener.h"
#include "nsIFrame.h"

class Area;
class nsIDOMEvent;
class nsRenderingContext;
class nsImageFrame;

class nsImageMap : public nsStubMutationObserver,
                   public nsIDOMEventListener
{
public:
  nsImageMap();

  nsresult Init(nsImageFrame* aImageFrame, nsIContent* aMap);

  /**
   * See if the given aX,aY <b>pixel</b> coordinates are in the image
   * map. If they are then true is returned and aContent points to the
   * found area. If the coordinates are not in the map then false
   * is returned.
   */
  bool IsInside(nscoord aX, nscoord aY,
                  nsIContent** aContent) const;

  void Draw(nsIFrame* aFrame, nsRenderingContext& aRC);
  
  /** 
   * Called just before the nsImageFrame releases us. 
   * Used to break the cycle caused by the DOM listener.
   */
  void Destroy();
  
  // nsISupports
  NS_DECL_ISUPPORTS

  // nsIMutationObserver
  NS_DECL_NSIMUTATIONOBSERVER_ATTRIBUTECHANGED
  NS_DECL_NSIMUTATIONOBSERVER_CONTENTAPPENDED
  NS_DECL_NSIMUTATIONOBSERVER_CONTENTINSERTED
  NS_DECL_NSIMUTATIONOBSERVER_CONTENTREMOVED
  NS_DECL_NSIMUTATIONOBSERVER_PARENTCHAINCHANGED  

  //nsIDOMEventListener
  NS_DECL_NSIDOMEVENTLISTENER

  nsresult GetBoundsForAreaContent(nsIContent *aContent,
                                   nsRect& aBounds);

protected:
  virtual ~nsImageMap();

  void FreeAreas();

  nsresult UpdateAreas();
  nsresult SearchForAreas(nsIContent* aParent, bool& aFoundArea,
                          bool& aFoundAnchor);

  nsresult AddArea(nsIContent* aArea);
 
  void MaybeUpdateAreas(nsIContent *aContent);

  nsImageFrame* mImageFrame;  // the frame that owns us
  nsCOMPtr<nsIContent> mMap;
  nsAutoTArray<Area*, 8> mAreas; // almost always has some entries
  bool mContainsBlockContents;
};

#endif /* nsImageMap_h */