gecko-dev/layout/xul/base/src/nsScrollbarFrame.h

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//
// nsScrollbarFrame
//

#ifndef nsScrollbarFrame_h__
#define nsScrollbarFrame_h__


#include "nsBoxFrame.h"
#include "nsIScrollbarFrame.h"

class nsISupportsArray;
class nsIScrollbarMediator;

nsIFrame* NS_NewScrollbarFrame(nsIPresShell* aPresShell, nsStyleContext* aContext);

class nsScrollbarFrame : public nsBoxFrame, public nsIScrollbarFrame
{
public:
    nsScrollbarFrame(nsIPresShell* aShell, nsStyleContext* aContext):
      nsBoxFrame(aShell, aContext), mScrollbarMediator(nsnull) {}

#ifdef DEBUG
  NS_IMETHOD GetFrameName(nsAString& aResult) const {
    return MakeFrameName(NS_LITERAL_STRING("ScrollbarFrame"), aResult);
  }
#endif

  // nsIFrame overrides
  NS_IMETHOD AttributeChanged(PRInt32 aNameSpaceID,
                              nsIAtom* aAttribute,
                              PRInt32 aModType);

  NS_IMETHOD QueryInterface(const nsIID& aIID, void** aInstancePtr);
  NS_IMETHOD_(nsrefcnt) AddRef() { return NS_OK; }
  NS_IMETHOD_(nsrefcnt) Release() { return NS_OK; }

   NS_IMETHOD HandlePress(nsPresContext* aPresContext,
                         nsGUIEvent *    aEvent,
                         nsEventStatus*  aEventStatus);

  NS_IMETHOD HandleMultiplePress(nsPresContext* aPresContext,
                         nsGUIEvent *    aEvent,
                         nsEventStatus*  aEventStatus);

  NS_IMETHOD HandleDrag(nsPresContext* aPresContext,
                        nsGUIEvent *    aEvent,
                        nsEventStatus*  aEventStatus);

  NS_IMETHOD HandleRelease(nsPresContext* aPresContext,
                           nsGUIEvent *    aEvent,
                           nsEventStatus*  aEventStatus);

  NS_IMETHOD Init(nsIContent*      aContent,
                  nsIFrame*        aParent,
                  nsIFrame*        aPrevInFlow);

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

  virtual PRBool IsContainingBlock() const;

  virtual nsIAtom* GetType() const;  

  // nsIScrollbarFrame
  virtual void SetScrollbarMediatorContent(nsIContent* aMediator);
  virtual nsIScrollbarMediator* GetScrollbarMediator();

  // nsBox methods

  /**
   * Treat scrollbars as clipping their children; overflowing children
   * will not be allowed to make NS_FRAME_OUTSIDE_CHILDREN on this
   * frame. This means that when the scroll code decides to hide a
   * scrollframe by setting its height or width to zero, that will
   * hide the children too.
   */
  virtual PRBool DoesClipChildren() { return PR_TRUE; }

private:
  nsCOMPtr<nsIContent> mScrollbarMediator;
}; // class nsScrollbarFrame

#endif