gecko-dev/layout/generic/nsImageMap.h

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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 * The Original Code is mozilla.org code.
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#ifndef nsImageMap_h___
#define nsImageMap_h___

#include "nsISupports.h"
#include "nsCoord.h"
#include "nsVoidArray.h"
#include "nsStubDocumentObserver.h"
#include "nsIDOMFocusListener.h"
#include "nsIFrame.h"
#include "nsIImageMap.h"
#include "nsIHTMLContent.h"

class nsIDOMHTMLAreaElement;
class nsIDOMHTMLMapElement;
class nsIPresContext;
class nsIRenderingContext;
class nsIURI;
class nsString;
class nsIDOMEvent;

class nsImageMap : public nsStubDocumentObserver, 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 NS_OK is returned and aAbsURL, aTarget, and
   * aAltText are filled in with the values from the underlying area
   * element. If the coordinates are not in the map then NS_NOT_INSIDE
   * is returned.
   */
  PRBool IsInside(nscoord aX, nscoord aY,
                  nsIContent** aContent,
                  nsAString& aAbsURL,
                  nsAString& aTarget,
                  nsAString& aAltText) const;

  /**
   * See if the given aX,aY <b>pixel</b> coordinates are in the image
   * map. If they are then NS_OK is returned otherwise NS_NOT_INSIDE
   * is returned.
   */
  PRBool IsInside(nscoord aX, nscoord aY) const;

  void Draw(nsIPresContext* aCX, 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

  // nsIDocumentObserver
  virtual void ContentChanged(nsIDocument* aDocument, nsIContent* aContent,
                              nsISupports* aSubContent);
  virtual void AttributeChanged(nsIDocument* aDocument, nsIContent* aContent,
                                PRInt32 aNameSpaceID, nsIAtom* aAttribute,
                                PRInt32 aModType);
  virtual void ContentAppended(nsIDocument* aDocument, nsIContent* aContainer,
                               PRInt32 aNewIndexInContainer);
  virtual void ContentInserted(nsIDocument* aDocument, nsIContent* aContainer,
                               nsIContent* aChild, PRInt32 aIndexInContainer);
  virtual void ContentReplaced(nsIDocument* aDocument, nsIContent* aContainer,
                               nsIContent* aOldChild, nsIContent* aNewChild,
                               PRInt32 aIndexInContainer);
  virtual void ContentRemoved(nsIDocument* aDocument, nsIContent* aContainer,
                              nsIContent* aChild, PRInt32 aIndexInContainer);

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

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

protected:
  virtual ~nsImageMap();

  void FreeAreas();

  nsresult UpdateAreas();
  nsresult UpdateAreasForBlock(nsIContent* aParent, PRBool* aFoundAnchor);

  static PRBool IsAncestorOf(nsIContent* aContent,
                             nsIContent* aAncestorContent);

  nsresult AddArea(nsIContent* aArea);
 
  nsresult ChangeFocus(nsIDOMEvent* aEvent, PRBool aFocus);
  nsresult Invalidate(nsIPresContext* aPresContext, nsIFrame* aFrame, nsRect& aRect);

  void MaybeUpdateAreas(nsIContent *aContent);

  nsIPresShell* mPresShell; // WEAK - owns the frame that owns us
  nsIFrame* mImageFrame;  // the frame that owns us
  nsIDocument* mDocument; // WEAK - the imagemap will not outlive the document
  nsCOMPtr<nsIHTMLContent> mMap;
  nsAutoVoidArray mAreas; // almost always has some entries
  PRBool mContainsBlockContents;
};

#endif /* nsImageMap_h___ */