gecko-dev/layout/generic/nsPlaceholderFrame.cpp

/* -*- 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): 
 */
#include "nsPlaceholderFrame.h"
#include "nsLineLayout.h"
#include "nsHTMLIIDs.h"
#include "nsIContent.h"
#include "nsIPresContext.h"
#include "nsIRenderingContext.h"
#include "nsIStyleContext.h"
#include "nsLayoutAtoms.h"

nsresult
NS_NewPlaceholderFrame(nsIPresShell* aPresShell, nsIFrame** aNewFrame)
{
  NS_PRECONDITION(aNewFrame, "null OUT ptr");
  if (nsnull == aNewFrame) {
    return NS_ERROR_NULL_POINTER;
  }
  nsPlaceholderFrame* it = new (aPresShell) nsPlaceholderFrame;
  if (nsnull == it) {
    return NS_ERROR_OUT_OF_MEMORY;
  }
  *aNewFrame = it;
  return NS_OK;
}

NS_IMETHODIMP
nsPlaceholderFrame::Reflow(nsIPresContext*          aPresContext,
                           nsHTMLReflowMetrics&     aDesiredSize,
                           const nsHTMLReflowState& aReflowState,
                           nsReflowStatus&          aStatus)
{
  DO_GLOBAL_REFLOW_COUNT("nsPlaceholderFrame", aReflowState.reason);
  aDesiredSize.width = 0;
  aDesiredSize.height = 0;
  aDesiredSize.ascent = 0;
  aDesiredSize.descent = 0;
  if (nsnull != aDesiredSize.maxElementSize) {
    aDesiredSize.maxElementSize->width = 0;
    aDesiredSize.maxElementSize->height = 0;
  }

  aStatus = NS_FRAME_COMPLETE;
  return NS_OK;
}

NS_IMETHODIMP
nsPlaceholderFrame::GetFrameType(nsIAtom** aType) const
{
  NS_PRECONDITION(nsnull != aType, "null OUT parameter pointer");
  *aType = nsLayoutAtoms::placeholderFrame; 
  NS_ADDREF(*aType);
  return NS_OK;
}

#ifdef DEBUG
NS_IMETHODIMP
nsPlaceholderFrame::Paint(nsIPresContext* aPresContext,
                          nsIRenderingContext& aRenderingContext,
                          const nsRect& aDirtyRect,
                          nsFramePaintLayer aWhichLayer)
{
  if ((NS_FRAME_PAINT_LAYER_DEBUG == aWhichLayer) && GetShowFrameBorders()) {
    float p2t;
    aPresContext->GetPixelsToTwips(&p2t);
    aRenderingContext.SetColor(NS_RGB(0, 255, 255));
    nscoord x = NSIntPixelsToTwips(-5, p2t);
    aRenderingContext.FillRect(x, 0, NSIntPixelsToTwips(13, p2t),
                               NSIntPixelsToTwips(3, p2t));
    nscoord y = NSIntPixelsToTwips(-10, p2t);
    aRenderingContext.FillRect(0, y, NSIntPixelsToTwips(3, p2t),
                               NSIntPixelsToTwips(10, p2t));
  }
  return NS_OK;
}

NS_IMETHODIMP
nsPlaceholderFrame::GetFrameName(nsString& aResult) const
{
  return MakeFrameName("Placeholder", aResult);
}

NS_IMETHODIMP
nsPlaceholderFrame::List(nsIPresContext* aPresContext, FILE* out, PRInt32 aIndent) const
{
  IndentBy(out, aIndent);
  ListTag(out);
#ifdef DEBUG_waterson
  fprintf(out, " [parent=%p]", mParent);
#endif
  nsIView* view;
  GetView(aPresContext, &view);
  if (nsnull != view) {
    fprintf(out, " [view=%p]", view);
  }
  fprintf(out, " {%d,%d,%d,%d}", mRect.x, mRect.y, mRect.width, mRect.height);
  if (0 != mState) {
    fprintf(out, " [state=%08x]", mState);
  }
  if (mOutOfFlowFrame) {
    fprintf(out, " outOfFlowFrame=");
    nsFrame::ListTag(out, mOutOfFlowFrame);
  }
  fputs("\n", out);
  return NS_OK;
}

NS_IMETHODIMP
nsPlaceholderFrame::SizeOf(nsISizeOfHandler* aHandler, PRUint32* aResult) const
{
  if (!aResult) {
    return NS_ERROR_NULL_POINTER;
  }
  *aResult = sizeof(*this);
  return NS_OK;
}
#endif