gecko-dev/layout/generic/nsIScrollableFrame.h
Benjamin Smedberg 3498a5f86e Bug 396185 - Make nsIFrame derivatives and helper abstract classes use a different dynamic-cast system than nsISupports:
* we know all types frames may be cast to at compile time, so instead of extensible GUID IIDs, use a big enum (see nsQueryFrame::FrameIID)
* eliminate all vestiges of refcounting, since frames aren't refcounted

Some frames (SVG frames in particular) still implement nsISupports-derived interfaces, for example nsISVGValue. There is a FrameIID for nsISVGValue that lets you go from a frame to the XPCOM interface, but you can't query back.

r+sr=roc

nsITextControlFrame didn't have an IID the first time around, but this wasn't a compile error because nsITextControlFrame::kFrameIID inherited from nsIFormControlFrame::kFrameIID. I've added a static analysis pass to verify the correct behavior, since I can't figure out a way to make the compiler do it.

--HG--
extra : rebase_source : 4894a2ca0278e2ab92f27459db77165f8348cf41
2009-01-12 14:20:59 -05:00

125 lines
4.5 KiB
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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
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* The Original Code is mozilla.org code.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
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* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* either of the GNU General Public License Version 2 or later (the "GPL"),
* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
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* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
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* ***** END LICENSE BLOCK ***** */
/*
* interface for rendering objects that wrap rendering objects that should
* be scrollable
*/
#ifndef nsIScrollFrame_h___
#define nsIScrollFrame_h___
#include "nsISupports.h"
#include "nsCoord.h"
#include "nsIViewManager.h"
#include "nsIScrollableViewProvider.h"
#include "nsPresContext.h"
#include "nsIFrame.h" // to get nsIBox, which is a typedef
class nsBoxLayoutState;
class nsIScrollableFrame : public nsIScrollableViewProvider {
public:
NS_DECLARE_FRAME_ACCESSOR(nsIScrollableFrame)
/**
* Get the frame that we are scrolling within the scrollable frame.
* @result child frame
*/
virtual nsIFrame* GetScrolledFrame() const = 0;
typedef nsPresContext::ScrollbarStyles ScrollbarStyles;
virtual ScrollbarStyles GetScrollbarStyles() const = 0;
/**
* Return the actual sizes of all possible scrollbars. Returns 0 for scrollbar
* positions that don't have a scrollbar or where the scrollbar is not visible.
* Do not call this while this frame's descendants are being reflowed, it won't be
* accurate.
*/
virtual nsMargin GetActualScrollbarSizes() const = 0;
/**
* Return the sizes of all scrollbars assuming that any scrollbars that could
* be visible due to overflowing content, are.
*/
virtual nsMargin GetDesiredScrollbarSizes(nsBoxLayoutState* aState) = 0;
virtual nsMargin GetDesiredScrollbarSizes(nsPresContext* aPresContext,
nsIRenderingContext* aRC) = 0;
/**
* Get the position of the scrolled view.
*/
virtual nsPoint GetScrollPosition() const = 0;
/**
* Scroll the view to the given x,y, update's the scrollbar's thumb
* positions and the view's offset. Clamps the values to be
* legal. Updates the display based on aUpdateFlags.
* @param aX left edge to scroll to
* @param aY top edge to scroll to
* @param aUpdateFlags indicate smooth or async scrolling
* @return error status
*/
virtual void ScrollTo(nsPoint aScrollPosition, PRUint32 aFlags = 0)=0;
virtual nsIScrollableView* GetScrollableView() = 0;
/**
* Set information about whether the vertical and horizontal scrollbars
* are currently visible
*/
virtual void SetScrollbarVisibility(PRBool aVerticalVisible, PRBool aHorizontalVisible) = 0;
virtual nsIBox* GetScrollbarBox(PRBool aVertical) = 0;
virtual void CurPosAttributeChanged(nsIContent* aChild, PRInt32 aModType) = 0;
/**
* This tells the scroll frame to try scrolling to the scroll
* position that was restored from the history. This must be called
* at least once after state has been restored. It is called by the
* scrolled frame itself during reflow, but sometimes state can be
* restored after reflows are done...
*/
virtual void ScrollToRestoredPosition() = 0;
};
#endif