gecko-dev/layout/generic/nsPlaceholderFrame.h

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#ifndef nsPlaceholderFrame_h___
#define nsPlaceholderFrame_h___

#include "nsSplittableFrame.h"

nsresult NS_NewPlaceholderFrame(nsIPresShell* aPresShell, nsIFrame**  aInstancePtrResult);

/**
 * Implementation of a frame that's used as a placeholder for a frame that
 * has been moved out of the flow
 */
class nsPlaceholderFrame : public nsSplittableFrame {
public:
  /**
   * Create a new placeholder frame
   */
  friend nsresult NS_NewPlaceholderFrame(nsIPresShell* aPresShell, nsIFrame**  aInstancePtrResult);
  nsPlaceholderFrame();
  virtual ~nsPlaceholderFrame();

  // Get/Set the associated out of flow frame
  nsIFrame*  GetOutOfFlowFrame() const {return mOutOfFlowFrame;}
  void       SetOutOfFlowFrame(nsIFrame* aFrame) {mOutOfFlowFrame = aFrame;}

  // nsIHTMLReflow overrides
  NS_IMETHOD Reflow(nsPresContext* aPresContext,
                    nsHTMLReflowMetrics& aDesiredSize,
                    const nsHTMLReflowState& aReflowState,
                    nsReflowStatus& aStatus);

  // nsIFrame overrides
#ifdef DEBUG
  NS_IMETHOD Paint(nsPresContext*      aPresContext,
                   nsIRenderingContext& aRenderingContext,
                   const nsRect&        aDirtyRect,
                   nsFramePaintLayer    aWhichLayer,
                   PRUint32             aFlags = 0);
  NS_IMETHOD List(nsPresContext* aPresContext, FILE* out, PRInt32 aIndent) const;
#endif

  /**
   * Get the "type" of the frame
   *
   * @see nsLayoutAtoms::placeholderFrame
   */
  virtual nsIAtom* GetType() const;

#ifdef DEBUG
  NS_IMETHOD GetFrameName(nsAString& aResult) const;
#endif

  virtual PRBool IsEmpty() { return PR_TRUE; }
  virtual PRBool IsFrameEmpty() { return PR_TRUE; }

protected:
  nsIFrame* mOutOfFlowFrame;
};

#endif /* nsPlaceholderFrame_h___ */