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

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

//
// nsScrollbarFrame
//

#ifndef nsScrollbarFrame_h__
#define nsScrollbarFrame_h__

#include "mozilla/Attributes.h"
#include "nsBoxFrame.h"

class nsIScrollbarMediator;

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

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

  NS_DECL_QUERYFRAME_TARGET(nsScrollbarFrame)

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

  // nsIFrame overrides
  NS_IMETHOD AttributeChanged(int32_t aNameSpaceID,
                              nsIAtom* aAttribute,
                              int32_t aModType) MOZ_OVERRIDE;

  NS_DECL_QUERYFRAME
  NS_DECL_FRAMEARENA_HELPERS

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

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

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

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

  virtual void Init(nsIContent*      aContent,
                    nsIFrame*        aParent,
                    nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;

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

  virtual nsIAtom* GetType() const MOZ_OVERRIDE;  

  void SetScrollbarMediatorContent(nsIContent* aMediator);
  nsIScrollbarMediator* GetScrollbarMediator();

  // nsBox methods

  /**
   * Treat scrollbars as clipping their children; overflowing children
   * will not be allowed to set an overflow rect 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 bool DoesClipChildren() MOZ_OVERRIDE { return true; }

  NS_IMETHOD GetMargin(nsMargin& aMargin) MOZ_OVERRIDE;

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

#endif