gecko-dev/layout/generic/nsPageContentFrame.cpp

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla 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/MPL/
*
* 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 the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
*
* 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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* ***** END LICENSE BLOCK ***** */
#include "nsPageContentFrame.h"
#include "nsPageFrame.h"
#include "nsPlaceholderFrame.h"
#include "nsCSSFrameConstructor.h"
#include "nsHTMLContainerFrame.h"
#include "nsHTMLParts.h"
#include "nsIContent.h"
#include "nsPresContext.h"
#include "nsIRenderingContext.h"
#include "nsGkAtoms.h"
#include "nsIPresShell.h"
#include "nsIDeviceContext.h"
#include "nsReadableUtils.h"
#include "nsSimplePageSequence.h"
#include "nsDisplayList.h"
nsIFrame*
NS_NewPageContentFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)
{
return new (aPresShell) nsPageContentFrame(aContext);
}
/* virtual */ nsSize
nsPageContentFrame::ComputeSize(nsIRenderingContext *aRenderingContext,
nsSize aCBSize, nscoord aAvailableWidth,
nsSize aMargin, nsSize aBorder, nsSize aPadding,
PRBool aShrinkWrap)
{
NS_ASSERTION(mPD, "Pages are supposed to have page data");
nscoord height = (!mPD || mPD->mReflowSize.height == NS_UNCONSTRAINEDSIZE)
? NS_UNCONSTRAINEDSIZE
: (mPD->mReflowSize.height - mPD->mReflowMargin.TopBottom());
return nsSize(aAvailableWidth, height);
}
/**
* Returns true if aFrame is a placeholder for one of our fixed frames.
*/
inline PRBool
nsPageContentFrame::IsFixedPlaceholder(nsIFrame* aFrame)
{
if (!aFrame || nsGkAtoms::placeholderFrame != aFrame->GetType())
return PR_FALSE;
return static_cast<nsPlaceholderFrame*>(aFrame)->GetOutOfFlowFrame()
->GetParent() == this;
}
/**
* Steals replicated fixed placeholder frames from aDocRoot so they don't
* get in the way of reflow.
*/
inline nsFrameList
nsPageContentFrame::StealFixedPlaceholders(nsIFrame* aDocRoot)
{
nsPresContext* presContext = PresContext();
nsFrameList list;
if (GetPrevInFlow()) {
for (nsIFrame* f = aDocRoot->GetFirstChild(nsnull);
IsFixedPlaceholder(f); f = aDocRoot->GetFirstChild(nsnull)) {
nsresult rv = static_cast<nsContainerFrame*>(aDocRoot)
->StealFrame(presContext, f);
NS_ENSURE_SUCCESS(rv, list);
list.AppendFrame(nsnull, f);
}
}
return list;
}
/**
* Restores stolen replicated fixed placeholder frames to aDocRoot.
*/
static inline nsresult
ReplaceFixedPlaceholders(nsIFrame* aDocRoot,
nsFrameList& aPlaceholderList)
{
nsresult rv = NS_OK;
if (aPlaceholderList.NotEmpty()) {
rv = static_cast<nsContainerFrame*>(aDocRoot)
->AddFrames(aPlaceholderList.FirstChild(), nsnull);
}
return rv;
}
NS_IMETHODIMP
nsPageContentFrame::Reflow(nsPresContext* aPresContext,
nsHTMLReflowMetrics& aDesiredSize,
const nsHTMLReflowState& aReflowState,
nsReflowStatus& aStatus)
{
DO_GLOBAL_REFLOW_COUNT("nsPageContentFrame");
DISPLAY_REFLOW(aPresContext, this, aReflowState, aDesiredSize, aStatus);
aStatus = NS_FRAME_COMPLETE; // initialize out parameter
nsresult rv = NS_OK;
// A PageContentFrame must always have one child: the doc root element's frame.
// We only need to get overflow frames if we don't already have that child;
// Also we need to avoid repeating the call to ReplicateFixedFrames.
nsPageContentFrame* prevPageContentFrame = static_cast<nsPageContentFrame*>
(GetPrevInFlow());
if (mFrames.IsEmpty() && prevPageContentFrame) {
// Pull the doc root frame's continuation and copy fixed frames.
nsIFrame* overflow = prevPageContentFrame->GetOverflowFrames(aPresContext, PR_TRUE);
NS_ASSERTION(overflow && !overflow->GetNextSibling(),
"must have doc root as pageContentFrame's only child");
nsHTMLContainerFrame::ReparentFrameView(aPresContext, overflow, prevPageContentFrame, this);
// Prepend overflow to the page content frame. There may already be
// children placeholders which don't get reflowed but must not be
// lost until the page content frame is destroyed.
mFrames.InsertFrames(this, nsnull, overflow);
nsresult rv = aPresContext->PresShell()->FrameConstructor()
->ReplicateFixedFrames(this);
NS_ENSURE_SUCCESS(rv, rv);
}
// Resize our frame allowing it only to be as big as we are
// XXX Pay attention to the page's border and padding...
if (mFrames.NotEmpty()) {
nsIFrame* frame = mFrames.FirstChild();
nsSize maxSize(aReflowState.availableWidth, aReflowState.availableHeight);
nsHTMLReflowState kidReflowState(aPresContext, aReflowState, frame, maxSize);
mPD->mPageContentSize = aReflowState.availableWidth;
// Get replicated fixed frames' placeholders out of the way
nsFrameList stolenPlaceholders = StealFixedPlaceholders(frame);
// Reflow the page content area
rv = ReflowChild(frame, aPresContext, aDesiredSize, kidReflowState, 0, 0, 0, aStatus);
NS_ENSURE_SUCCESS(rv, rv);
// Put removed fixed placeholders back
rv = ReplaceFixedPlaceholders(frame, stolenPlaceholders);
NS_ENSURE_SUCCESS(rv, rv);
if (!NS_FRAME_IS_FULLY_COMPLETE(aStatus)) {
nsIFrame* nextFrame = frame->GetNextInFlow();
NS_ASSERTION(nextFrame || aStatus & NS_FRAME_REFLOW_NEXTINFLOW,
"If it's incomplete and has no nif yet, it must flag a nif reflow.");
if (!nextFrame) {
nsresult rv = nsHTMLContainerFrame::CreateNextInFlow(aPresContext,
this, frame, nextFrame);
NS_ENSURE_SUCCESS(rv, rv);
frame->SetNextSibling(nextFrame->GetNextSibling());
nextFrame->SetNextSibling(nsnull);
SetOverflowFrames(aPresContext, nextFrame);
// Root overflow containers will be normal children of
// the pageContentFrame, but that's ok because there
// aren't any other frames we need to isolate them from
// during reflow.
}
if (NS_FRAME_OVERFLOW_IS_INCOMPLETE(aStatus)) {
nextFrame->AddStateBits(NS_FRAME_IS_OVERFLOW_CONTAINER);
}
}
// The document element's background should cover the entire canvas, so
// take into account the combined area and any space taken up by
// absolutely positioned elements
nsMargin padding(0,0,0,0);
// XXXbz this screws up percentage padding (sets padding to zero
// in the percentage padding case)
kidReflowState.mStylePadding->GetPadding(padding);
// First check the combined area
if (NS_FRAME_OUTSIDE_CHILDREN & frame->GetStateBits()) {
// The background covers the content area and padding area, so check
// for children sticking outside the child frame's padding edge
if (aDesiredSize.mOverflowArea.XMost() > aDesiredSize.width) {
mPD->mPageContentXMost =
aDesiredSize.mOverflowArea.XMost() +
kidReflowState.mStyleBorder->GetBorderWidth(NS_SIDE_RIGHT) +
padding.right;
}
}
// Place and size the child
FinishReflowChild(frame, aPresContext, &kidReflowState, aDesiredSize, 0, 0, 0);
NS_ASSERTION(aPresContext->IsDynamic() || !NS_FRAME_IS_FULLY_COMPLETE(aStatus) ||
!frame->GetNextInFlow(), "bad child flow list");
}
// Reflow our fixed frames
nsReflowStatus fixedStatus = NS_FRAME_COMPLETE;
mFixedContainer.Reflow(this, aPresContext, aReflowState, fixedStatus,
aReflowState.availableWidth,
aReflowState.availableHeight,
PR_FALSE, PR_TRUE, PR_TRUE); // XXX could be optimized
NS_ASSERTION(NS_FRAME_IS_COMPLETE(fixedStatus), "fixed frames can be truncated, but not incomplete");
// Return our desired size
aDesiredSize.width = aReflowState.availableWidth;
if (aReflowState.availableHeight != NS_UNCONSTRAINEDSIZE) {
aDesiredSize.height = aReflowState.availableHeight;
}
NS_FRAME_SET_TRUNCATION(aStatus, aReflowState, aDesiredSize);
return NS_OK;
}
nsIAtom*
nsPageContentFrame::GetType() const
{
return nsGkAtoms::pageContentFrame;
}
#ifdef DEBUG
NS_IMETHODIMP
nsPageContentFrame::GetFrameName(nsAString& aResult) const
{
return MakeFrameName(NS_LITERAL_STRING("PageContent"), aResult);
}
#endif
/* virtual */ PRBool
nsPageContentFrame::IsContainingBlock() const
{
return PR_TRUE;
}