gecko-dev/accessible/src/base/nsAccessible.h

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#ifndef _nsAccessible_H_
#define _nsAccessible_H_

#include "nsAccessNodeWrap.h"
#include "nsIAccessible.h"
#include "nsPIAccessible.h"
#include "nsWeakReference.h"
#include "nsIDOMNodeList.h"
#include "nsString.h"

struct nsRect;
class nsIContent;
class nsIFrame;
class nsIPresShell;
class nsIDOMNode;
class nsIAtom;

// When mNextSibling is set to this, it indicates there ar eno more siblings
#define DEAD_END_ACCESSIBLE NS_STATIC_CAST(nsIAccessible*, (void*)1)

struct nsStateMapEntry
{
  const char* attributeName;  // magic value of nsnull means last entry in map
  const char* attributeValue; // magic value of nsnull means any value
  PRUint32 state;       // OR state with this
};

struct nsRoleMapEntry
{
  const char *roleString; // such as "button"
  PRUint32 role;   // use this role
  PRUint32 state;  // always OR state with this
  // For this role with a DOM attribute/value match definined in
  // nsStateMapEntry.attributeName && .attributeValue, OR accessible state with
  // nsStateMapEntry.state
  // Currently you can have up to 3 DOM attributes with accessible state mappings.
  // A variable sized array would not allow use of C++'s struct initialization feature.
  nsStateMapEntry attributeMap1;
  nsStateMapEntry attributeMap2;
  nsStateMapEntry attributeMap3;
};

class nsAccessible : public nsAccessNodeWrap, 
                     public nsIAccessible, 
                     public nsPIAccessible
{
public:
  // to eliminate the confusion of "magic numbers" -- if ( 0 ){ foo; }
  enum { eAction_Switch=0, eAction_Jump=0, eAction_Click=0, eAction_Select=0, eAction_Expand=1 };
  // how many actions
  enum { eNo_Action=0, eSingle_Action=1, eDouble_Action=2 }; 

  nsAccessible(nsIDOMNode* aNode, nsIWeakReference* aShell);
  virtual ~nsAccessible();

  NS_DECL_ISUPPORTS_INHERITED
  NS_DECL_NSIACCESSIBLE
  NS_DECL_NSPIACCESSIBLE

  // nsIAccessNode
  NS_IMETHOD Init();
  NS_IMETHOD Shutdown();

  // Support GetFinalState(), GetFinalValue()
  NS_IMETHOD GetState(PRUint32 *aState);
  NS_IMETHOD GetValue(nsAString & aValue);

#ifdef MOZ_ACCESSIBILITY_ATK
  static nsresult GetParentBlockNode(nsIPresShell *aPresShell, nsIDOMNode *aCurrentNode, nsIDOMNode **aBlockNode);
  static nsIFrame* GetParentBlockFrame(nsIFrame *aFrame);
  static PRBool FindTextFrame(PRInt32 &index, nsPresContext *aPresContext, nsIFrame *aCurFrame, 
                                   nsIFrame **aFirstTextFrame, const nsIFrame *aTextFrame);
#endif

  static PRBool IsCorrectFrameType(nsIFrame* aFrame, nsIAtom* aAtom);

protected:
  PRUint32 MappedAttrState(nsIContent *aContent, nsStateMapEntry *aStateMapEntry);
  virtual nsIFrame* GetBoundsFrame();
  virtual void GetBoundsRect(nsRect& aRect, nsIFrame** aRelativeFrame);
  PRBool IsPartiallyVisible(PRBool *aIsOffscreen); 
  static nsIContent *GetLabelForId(nsIContent *aLookContent, nsIAtom *forAttrib,
                                const nsAString *aId);
  static nsIContent *GetXULLabelContent(nsIContent *aForNode);
  static nsIContent *GetHTMLLabelContent(nsIContent *aForNode);
  nsresult GetHTMLName(nsAString& _retval);
  nsresult GetXULName(nsAString& _retval);
  // For accessibles that are not lists of choices, the name of the subtree should be the 
  // sum of names in the subtree
  nsresult AppendFlatStringFromSubtree(nsIContent *aContent, nsAString *aFlatString);
  nsresult AppendFlatStringFromContentNode(nsIContent *aContent, nsAString *aFlatString);
  nsresult AppendStringWithSpaces(nsAString *aFlatString, const nsAString& textEquivalent);

  // helper method to verify frames
  static nsresult GetFullKeyName(const nsAString& aModifierName, const nsAString& aKeyName, nsAString& aStringOut);
  static nsresult GetTranslatedString(const nsAString& aKey, nsAString& aStringOut);
  void GetScreenOrigin(nsPresContext *aPresContext, nsIFrame *aFrame, nsRect *aRect);
  nsresult AppendFlatStringFromSubtreeRecurse(nsIContent *aContent, nsAString *aFlatString);
  virtual void CacheChildren(PRBool aWalkAnonContent);

  // Data Members
  nsCOMPtr<nsIAccessible> mParent;
  nsIAccessible *mFirstChild, *mNextSibling;
  nsRoleMapEntry *mRoleMapEntry; // Non-null indicates author-supplied role; possibly state & value as well

  static nsRoleMapEntry gWAIRoleMap[];
  static nsStateMapEntry gDisabledStateMap;
};


#endif