1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/layout/generic/nsAbsoluteContainingBlock.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,145 @@
1.4 +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.6 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.7 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.8 +
1.9 +/*
1.10 + * code for managing absolutely positioned children of a rendering
1.11 + * object that is a containing block for them
1.12 + */
1.13 +
1.14 +#ifndef nsAbsoluteContainingBlock_h___
1.15 +#define nsAbsoluteContainingBlock_h___
1.16 +
1.17 +#include "nsFrameList.h"
1.18 +#include "nsIFrame.h"
1.19 +
1.20 +class nsContainerFrame;
1.21 +class nsHTMLReflowState;
1.22 +class nsPresContext;
1.23 +
1.24 +/**
1.25 + * This class contains the logic for being an absolute containing block. This
1.26 + * class is used within viewport frames (for frames representing content with
1.27 + * fixed position) and blocks (for frames representing absolutely positioned
1.28 + * content), since each set of frames is absolutely positioned with respect to
1.29 + * its parent.
1.30 + *
1.31 + * There is no principal child list, just a named child list which contains
1.32 + * the absolutely positioned frames (kAbsoluteList or kFixedList).
1.33 + *
1.34 + * All functions include as the first argument the frame that is delegating
1.35 + * the request.
1.36 + */
1.37 +class nsAbsoluteContainingBlock
1.38 +{
1.39 +public:
1.40 + typedef nsIFrame::ChildListID ChildListID;
1.41 +
1.42 + nsAbsoluteContainingBlock(ChildListID aChildListID)
1.43 +#ifdef DEBUG
1.44 + : mChildListID(aChildListID)
1.45 +#endif
1.46 + {
1.47 + MOZ_ASSERT(mChildListID == nsIFrame::kAbsoluteList ||
1.48 + mChildListID == nsIFrame::kFixedList,
1.49 + "should either represent position:fixed or absolute content");
1.50 + }
1.51 +
1.52 + const nsFrameList& GetChildList() const { return mAbsoluteFrames; }
1.53 + void AppendChildList(nsTArray<nsIFrame::ChildList>* aLists,
1.54 + ChildListID aListID) const
1.55 + {
1.56 + NS_ASSERTION(aListID == mChildListID, "wrong list ID");
1.57 + GetChildList().AppendIfNonempty(aLists, aListID);
1.58 + }
1.59 +
1.60 + nsresult SetInitialChildList(nsIFrame* aDelegatingFrame,
1.61 + ChildListID aListID,
1.62 + nsFrameList& aChildList);
1.63 + nsresult AppendFrames(nsIFrame* aDelegatingFrame,
1.64 + ChildListID aListID,
1.65 + nsFrameList& aFrameList);
1.66 + nsresult InsertFrames(nsIFrame* aDelegatingFrame,
1.67 + ChildListID aListID,
1.68 + nsIFrame* aPrevFrame,
1.69 + nsFrameList& aFrameList);
1.70 + void RemoveFrame(nsIFrame* aDelegatingFrame,
1.71 + ChildListID aListID,
1.72 + nsIFrame* aOldFrame);
1.73 +
1.74 + /**
1.75 + * Called by the delegating frame after it has done its reflow first. This
1.76 + * function will reflow any absolutely positioned child frames that need to
1.77 + * be reflowed, e.g., because the absolutely positioned child frame has
1.78 + * 'auto' for an offset, or a percentage based width or height.
1.79 + *
1.80 + * @param aOverflowAreas, if non-null, is unioned with (in the local
1.81 + * coordinate space) the overflow areas of the absolutely positioned
1.82 + * children.
1.83 + *
1.84 + * @param aReflowStatus is assumed to be already-initialized, e.g. with the
1.85 + * status of the delegating frame's main reflow. This function merges in the
1.86 + * statuses of the absolutely positioned children's reflows.
1.87 + */
1.88 + nsresult Reflow(nsContainerFrame* aDelegatingFrame,
1.89 + nsPresContext* aPresContext,
1.90 + const nsHTMLReflowState& aReflowState,
1.91 + nsReflowStatus& aReflowStatus,
1.92 + const nsRect& aContainingBlock,
1.93 + bool aConstrainHeight,
1.94 + bool aCBWidthChanged,
1.95 + bool aCBHeightChanged,
1.96 + nsOverflowAreas* aOverflowAreas);
1.97 +
1.98 + void DestroyFrames(nsIFrame* aDelegatingFrame,
1.99 + nsIFrame* aDestructRoot);
1.100 +
1.101 + bool HasAbsoluteFrames() const { return mAbsoluteFrames.NotEmpty(); }
1.102 +
1.103 + /**
1.104 + * Mark our size-dependent absolute frames with NS_FRAME_HAS_DIRTY_CHILDREN
1.105 + * so that we'll make sure to reflow them.
1.106 + */
1.107 + void MarkSizeDependentFramesDirty();
1.108 +
1.109 + /**
1.110 + * Mark all our absolute frames with NS_FRAME_IS_DIRTY.
1.111 + */
1.112 + void MarkAllFramesDirty();
1.113 +
1.114 +protected:
1.115 + /**
1.116 + * Returns true if the position of aFrame depends on the position of
1.117 + * its placeholder or if the position or size of aFrame depends on a
1.118 + * containing block dimension that changed.
1.119 + */
1.120 + bool FrameDependsOnContainer(nsIFrame* aFrame, bool aCBWidthChanged,
1.121 + bool aCBHeightChanged);
1.122 +
1.123 + nsresult ReflowAbsoluteFrame(nsIFrame* aDelegatingFrame,
1.124 + nsPresContext* aPresContext,
1.125 + const nsHTMLReflowState& aReflowState,
1.126 + const nsRect& aContainingBlockRect,
1.127 + bool aConstrainHeight,
1.128 + nsIFrame* aKidFrame,
1.129 + nsReflowStatus& aStatus,
1.130 + nsOverflowAreas* aOverflowAreas);
1.131 +
1.132 + /**
1.133 + * Mark our absolute frames dirty.
1.134 + * @param aMarkAllDirty if true, all will be marked with NS_FRAME_IS_DIRTY.
1.135 + * Otherwise, the size-dependant ones will be marked with
1.136 + * NS_FRAME_HAS_DIRTY_CHILDREN.
1.137 + */
1.138 + void DoMarkFramesDirty(bool aMarkAllDirty);
1.139 +
1.140 +protected:
1.141 + nsFrameList mAbsoluteFrames; // additional named child list
1.142 +
1.143 +#ifdef DEBUG
1.144 + ChildListID const mChildListID; // kFixedList or kAbsoluteList
1.145 +#endif
1.146 +};
1.147 +
1.148 +#endif /* nsnsAbsoluteContainingBlock_h___ */
