gecko-dev/layout/generic/nsHTMLContainerFrame.h

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 *
 * The contents of this file are subject to the Netscape Public
 * License Version 1.1 (the "License"); you may not use this file
 * except in compliance with the License. You may obtain a copy of
 * the License at http://www.mozilla.org/NPL/
 *
 * Software distributed under the License is distributed on an "AS
 * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
 * implied. See the License for the specific language governing
 * rights and limitations under the License.
 *
 * The Original Code is mozilla.org code.
 *
 * The Initial Developer of the Original Code is Netscape
 * Communications Corporation.  Portions created by Netscape are
 * Copyright (C) 1998 Netscape Communications Corporation. All
 * Rights Reserved.
 *
 * Contributor(s): 
 */
#ifndef nsHTMLContainerFrame_h___
#define nsHTMLContainerFrame_h___

#include "nsContainerFrame.h"
class nsString;
class nsAbsoluteFrame;
class nsPlaceholderFrame;
struct nsStyleDisplay;
struct nsStylePosition;

// Some macros for container classes to do sanity checking on
// width/height/x/y values computed during reflow.
#ifdef DEBUG
#define CRAZY_W 500000

// 100000 lines, approximately. Assumes p2t is 15 and 15 pixels per line
#define CRAZY_H 22500000

#define CRAZY_WIDTH(_x) (((_x) < -CRAZY_W) || ((_x) > CRAZY_W))
#define CRAZY_HEIGHT(_y) (((_y) < -CRAZY_H) || ((_y) > CRAZY_H))
#endif

// Base class for html container frames that provides common
// functionality.
class nsHTMLContainerFrame : public nsContainerFrame {
public:
  NS_IMETHOD  Paint(nsIPresContext* aPresContext,
                    nsIRenderingContext& aRenderingContext,
                    const nsRect& aDirtyRect,
                    nsFramePaintLayer aWhichLayer);

  /**
   * Helper method to create next-in-flows if necessary. If aFrame
   * already has a next-in-flow then this method does
   * nothing. Otherwise, a new continuation frame is created and
   * linked into the flow. In addition, the new frame becomes the
   * next-sibling of aFrame.
   */
  static nsresult CreateNextInFlow(nsIPresContext* aPresContext,
                                   nsIFrame* aOuterFrame,
                                   nsIFrame* aFrame,
                                   nsIFrame*& aNextInFlowResult);

  /**
   * Helper method to wrap views around frames. Used by containers
   * under special circumstances (can be used by leaf frames as well)
   * @param aContentParentFrame
   *         if non-null, this is the frame 
   *         which would have held aFrame except that aFrame was reparented
   *         to an alternative geometric parent. This is necessary
   *         so that aFrame can remember to get its Z-order from 
   *         aContentParentFrame.
   */
  static nsresult CreateViewForFrame(nsIPresContext* aPresContext,
                                     nsIFrame* aFrame,
                                     nsIStyleContext* aStyleContext,
                                     nsIFrame* aContentParentFrame,
                                     PRBool aForce);

  static nsresult ReparentFrameView(nsIPresContext* aPresContext,
                                    nsIFrame*       aChildFrame,
                                    nsIFrame*       aOldParentFrame,
                                    nsIFrame*       aNewParentFrame);
  
  static nsresult ReparentFrameViewList(nsIPresContext* aPresContext,
                                        nsIFrame*       aChildFrameList,
                                        nsIFrame*       aOldParentFrame,
                                        nsIFrame*       aNewParentFrame);

protected:
  virtual PRIntn GetSkipSides() const = 0;
};

#endif /* nsHTMLContainerFrame_h___ */