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 "nsIDOMFocusListener.h"
#include "nsIFrame.h"
#include "nsIImageMap.h"

class nsIDOMHTMLAreaElement;
class nsIDOMHTMLMapElement;
class nsPresContext;
class nsIRenderingContext;
class nsIURI;
class nsString;
class nsIDOMEvent;
class Area;

class nsImageMap : public nsStubMutationObserver, public nsIDOMFocusListener,
                   public nsIImageMap
{
public:
  nsImageMap();

  nsresult Init(nsIPresShell* aPresShell, nsIFrame* aImageFrame, nsIDOMHTMLMapElement* aMap);

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

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

  // nsIMutationObserver
  NS_DECL_NSIMUTATIONOBSERVER_ATTRIBUTECHANGED
  NS_DECL_NSIMUTATIONOBSERVER_CONTENTAPPENDED
  NS_DECL_NSIMUTATIONOBSERVER_CONTENTINSERTED
  NS_DECL_NSIMUTATIONOBSERVER_CONTENTREMOVED

  //nsIDOMFocusListener
  NS_IMETHOD Focus(nsIDOMEvent* aEvent);
  NS_IMETHOD Blur(nsIDOMEvent* aEvent);
  NS_IMETHOD HandleEvent(nsIDOMEvent* aEvent);

  //nsIImageMap
  NS_IMETHOD GetBoundsForAreaContent(nsIContent *aContent, 
                                     nsRect& aBounds);

protected:
  virtual ~nsImageMap();

  void FreeAreas();

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

  nsresult AddArea(nsIContent* aArea);
 
  nsresult ChangeFocus(nsIDOMEvent* aEvent, PRBool aFocus);

  void MaybeUpdateAreas(nsIContent *aContent);

  nsIPresShell* mPresShell; // WEAK - owns the frame that owns us
  nsIFrame* mImageFrame;  // the frame that owns us
  nsCOMPtr<nsIContent> mMap;
  nsAutoTArray<Area*, 8> mAreas; // almost always has some entries
  PRBool mContainsBlockContents;
};

#endif /* nsImageMap_h___ */