layout/generic/nsPageContentFrame.cpp

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* ***** BEGIN LICENSE BLOCK *****
   3  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   4  *
   5  * The contents of this file are subject to the Mozilla Public License Version
   6  * 1.1 (the "License"); you may not use this file except in compliance with
   7  * the License. You may obtain a copy of the License at
   8  * http://www.mozilla.org/MPL/
   9  *
  10  * Software distributed under the License is distributed on an "AS IS" basis,
  11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  12  * for the specific language governing rights and limitations under the
  13  * License.
  14  *
  15  * The Original Code is mozilla.org code.
  16  *
  17  * The Initial Developer of the Original Code is
  18  * Netscape Communications Corporation.
  19  * Portions created by the Initial Developer are Copyright (C) 1998
  20  * the Initial Developer. All Rights Reserved.
  21  *
  22  * Contributor(s):
  23  *
  24  * Alternatively, the contents of this file may be used under the terms of
  25  * either of the GNU General Public License Version 2 or later (the "GPL"),
  26  * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
  27  * in which case the provisions of the GPL or the LGPL are applicable instead
  28  * of those above. If you wish to allow use of your version of this file only
  29  * under the terms of either the GPL or the LGPL, and not to allow others to
  30  * use your version of this file under the terms of the MPL, indicate your
  31  * decision by deleting the provisions above and replace them with the notice
  32  * and other provisions required by the GPL or the LGPL. If you do not delete
  33  * the provisions above, a recipient may use your version of this file under
  34  * the terms of any one of the MPL, the GPL or the LGPL.
  35  *
  36  * ***** END LICENSE BLOCK ***** */
  37 #include "nsPageContentFrame.h"
  38 #include "nsPageFrame.h"
  39 #include "nsPlaceholderFrame.h"
  40 #include "nsCSSFrameConstructor.h"
  41 #include "nsHTMLContainerFrame.h"
  42 #include "nsHTMLParts.h"
  43 #include "nsIContent.h"
  44 #include "nsPresContext.h"
  45 #include "nsIRenderingContext.h"
  46 #include "nsGkAtoms.h"
  47 #include "nsIPresShell.h"
  48 #include "nsIDeviceContext.h"
  49 #include "nsReadableUtils.h"
  50 #include "nsSimplePageSequence.h"
  51 #include "nsDisplayList.h"
  52
  53 nsIFrame*
  54 NS_NewPageContentFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)
  55 {
  56   return new (aPresShell) nsPageContentFrame(aContext);
  57 }
  58
  59 /* virtual */ nsSize
  60 nsPageContentFrame::ComputeSize(nsIRenderingContext *aRenderingContext,
  61                                 nsSize aCBSize, nscoord aAvailableWidth,
  62                                 nsSize aMargin, nsSize aBorder, nsSize aPadding,
  63                                 PRBool aShrinkWrap)
  64 {
  65   NS_ASSERTION(mPD, "Pages are supposed to have page data");
  66   nscoord height = (!mPD || mPD->mReflowSize.height == NS_UNCONSTRAINEDSIZE)
  67                    ? NS_UNCONSTRAINEDSIZE
  68                    : (mPD->mReflowSize.height - mPD->mReflowMargin.TopBottom());
  69   return nsSize(aAvailableWidth, height);
  70 }
  71
  72 NS_IMETHODIMP
  73 nsPageContentFrame::Reflow(nsPresContext*           aPresContext,
  74                            nsHTMLReflowMetrics&     aDesiredSize,
  75                            const nsHTMLReflowState& aReflowState,
  76                            nsReflowStatus&          aStatus)
  77 {
  78   DO_GLOBAL_REFLOW_COUNT("nsPageContentFrame");
  79   DISPLAY_REFLOW(aPresContext, this, aReflowState, aDesiredSize, aStatus);
  80   aStatus = NS_FRAME_COMPLETE;  // initialize out parameter
  81   nsresult rv = NS_OK;
  82
  83   if (GetPrevInFlow() && (GetStateBits() & NS_FRAME_FIRST_REFLOW)) {
  84     nsresult rv = aPresContext->PresShell()->FrameConstructor()
  85                     ->ReplicateFixedFrames(this);
  86     NS_ENSURE_SUCCESS(rv, rv);
  87   }
  88
  89   // A PageContentFrame must always have one child: the canvas frame.
  90   // Resize our frame allowing it only to be as big as we are
  91   // XXX Pay attention to the page's border and padding...
  92   if (mFrames.NotEmpty()) {
  93     nsIFrame* frame = mFrames.FirstChild();
  94     nsSize  maxSize(aReflowState.availableWidth, aReflowState.availableHeight);
  95     nsHTMLReflowState kidReflowState(aPresContext, aReflowState, frame, maxSize);
  96     kidReflowState.SetComputedHeight(aReflowState.availableHeight);
  97
  98     mPD->mPageContentSize  = aReflowState.availableWidth;
  99
 100     // Reflow the page content area
 101     rv = ReflowChild(frame, aPresContext, aDesiredSize, kidReflowState, 0, 0, 0, aStatus);
 102     NS_ENSURE_SUCCESS(rv, rv);
 103
 104     // The document element's background should cover the entire canvas, so
 105     // take into account the combined area and any space taken up by
 106     // absolutely positioned elements
 107     nsMargin padding(0,0,0,0);
 108
 109     // XXXbz this screws up percentage padding (sets padding to zero
 110     // in the percentage padding case)
 111     kidReflowState.mStylePadding->GetPadding(padding);
 112
 113     // First check the combined area
 114     if (NS_FRAME_OUTSIDE_CHILDREN & frame->GetStateBits()) {
 115       // The background covers the content area and padding area, so check
 116       // for children sticking outside the child frame's padding edge
 117       if (aDesiredSize.mOverflowArea.XMost() > aDesiredSize.width) {
 118         mPD->mPageContentXMost =
 119           aDesiredSize.mOverflowArea.XMost() +
 120           kidReflowState.mStyleBorder->GetActualBorderWidth(NS_SIDE_RIGHT) +
 121           padding.right;
 122       }
 123     }
 124
 125     // Place and size the child
 126     FinishReflowChild(frame, aPresContext, &kidReflowState, aDesiredSize, 0, 0, 0);
 127
 128     NS_ASSERTION(aPresContext->IsDynamic() || !NS_FRAME_IS_FULLY_COMPLETE(aStatus) ||
 129                   !frame->GetNextInFlow(), "bad child flow list");
 130   }
 131   // Reflow our fixed frames
 132   nsReflowStatus fixedStatus = NS_FRAME_COMPLETE;
 133   mFixedContainer.Reflow(this, aPresContext, aReflowState, fixedStatus,
 134                          aReflowState.availableWidth,
 135                          aReflowState.availableHeight,
 136                          PR_FALSE, PR_TRUE, PR_TRUE); // XXX could be optimized
 137   NS_ASSERTION(NS_FRAME_IS_COMPLETE(fixedStatus), "fixed frames can be truncated, but not incomplete");
 138
 139   // Return our desired size
 140   aDesiredSize.width = aReflowState.availableWidth;
 141   if (aReflowState.availableHeight != NS_UNCONSTRAINEDSIZE) {
 142     aDesiredSize.height = aReflowState.availableHeight;
 143   }
 144
 145   NS_FRAME_SET_TRUNCATION(aStatus, aReflowState, aDesiredSize);
 146   return NS_OK;
 147 }
 148
 149 nsIAtom*
 150 nsPageContentFrame::GetType() const
 151 {
 152   return nsGkAtoms::pageContentFrame;
 153 }
 154
 155 #ifdef DEBUG
 156 NS_IMETHODIMP
 157 nsPageContentFrame::GetFrameName(nsAString& aResult) const
 158 {
 159   return MakeFrameName(NS_LITERAL_STRING("PageContent"), aResult);
 160 }
 161 #endif
 162
 163 /* virtual */ PRBool
 164 nsPageContentFrame::IsContainingBlock() const
 165 {
 166   return PR_TRUE;
 167 }