gecko/content/smil/nsSMILCSSProperty.h

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 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
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 * The Original Code is the Mozilla SMIL module.
 *
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 * Contributor(s):
 *   Daniel Holbert <dholbert@mozilla.com>
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/* representation of a SMIL-animatable CSS property on an element */

#ifndef NS_SMILCSSPROPERTY_H_
#define NS_SMILCSSPROPERTY_H_

#include "nsISMILAttr.h"
#include "nsIAtom.h"
#include "nsCSSProperty.h"
#include "nsCSSValue.h"

class nsIContent;
class nsCSSDeclaration;

/**
 * nsSMILCSSProperty: Implements the nsISMILAttr interface for SMIL animations
 * that target CSS properties.  Represents a particular animation-targeted CSS
 * property on a particular element.
 */
class nsSMILCSSProperty : public nsISMILAttr
{
public:
  /**
   * Constructs a new nsSMILCSSProperty.
   * @param  aPropID   The CSS property we're interested in animating.
   * @param  aElement  The element whose CSS property is being animated.
   */
  nsSMILCSSProperty(nsCSSProperty aPropID, nsIContent* aElement);

  // nsISMILAttr methods
  virtual nsresult ValueFromString(const nsAString& aStr,
                                   const nsISMILAnimationElement* aSrcElement,
                                   nsSMILValue& aValue,
                                   PRBool& aCanCache) const;
  virtual nsSMILValue GetBaseValue() const;
  virtual nsresult    SetAnimValue(const nsSMILValue& aValue);
  virtual void        ClearAnimValue();

  /**
   * Utility method - returns PR_TRUE if the given property is supported for
   * SMIL animation.
   *
   * @param   aProperty  The property to check for animation support.
   * @return  PR_TRUE if the given property is supported for SMIL animation, or
   *          PR_FALSE otherwise
   */
  static PRBool IsPropertyAnimatable(nsCSSProperty aPropID);

protected:
  nsCSSProperty mPropID;
  // Using non-refcounted pointer for mElement -- we know mElement will stay
  // alive for my lifetime because a nsISMILAttr (like me) only lives as long
  // as the Compositing step, and DOM elements don't get a chance to die during
  // that time.
  nsIContent*   mElement;
};

#endif // NS_SMILCSSPROPERTY_H_