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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
- * of those above. If you wish to allow use of your version of this file only
- * under the terms of either the GPL or the LGPL, and not to allow others to
- * use your version of this file under the terms of the MPL, indicate your
- * decision by deleting the provisions above and replace them with the notice
- * and other provisions required by the GPL or the LGPL. If you do not delete
- * the provisions above, a recipient may use your version of this file under
- * the terms of any one of the MPL, the GPL or the LGPL.
- *
- * ***** END LICENSE BLOCK ***** */
- #ifndef nsHTMLReflowState_h___
- #define nsHTMLReflowState_h___
-
- #include "nsMargin.h"
- #include "nsStyleCoord.h"
-
- class nsIFrame;
- class nsPresContext;
- class nsReflowPath;
- class nsIRenderingContext;
- class nsSpaceManager;
- class nsLineLayout;
- class nsIPercentHeightObserver;
-
- struct nsStyleDisplay;
- struct nsStyleVisibility;
- struct nsStylePosition;
- struct nsStyleBorder;
- struct nsStyleMargin;
- struct nsStylePadding;
- struct nsStyleText;
- struct nsHypotheticalBox;
-
- /**
- * Constant used to indicate an unconstrained size.
- *
- * @see #Reflow()
- */
- #define NS_UNCONSTRAINEDSIZE NS_MAXSIZE
-
- /**
- * The reason the frame is being reflowed.
- *
- * XXX Should probably be a #define so it can be extended for specialized
- * reflow interfaces...
- *
- * @see nsHTMLReflowState
- */
- enum nsReflowReason {
- eReflowReason_Initial = 0, // initial reflow of a newly created frame
- eReflowReason_Incremental = 1, // an incremental change has occured. see the reflow command for details
- eReflowReason_Resize = 2, // general request to determine a desired size
- eReflowReason_StyleChange = 3, // request to reflow because of a style change. Note: you must reflow
- // all your child frames
- eReflowReason_Dirty = 4 // request to reflow because you and/or your children are dirty
- };
-
- /**
- * CSS Frame type. Included as part of the reflow state.
- */
- typedef PRUint32 nsCSSFrameType;
-
- #define NS_CSS_FRAME_TYPE_UNKNOWN 0
- #define NS_CSS_FRAME_TYPE_INLINE 1
- #define NS_CSS_FRAME_TYPE_BLOCK 2 /* block-level in normal flow */
- #define NS_CSS_FRAME_TYPE_FLOATING 3
- #define NS_CSS_FRAME_TYPE_ABSOLUTE 4
- #define NS_CSS_FRAME_TYPE_INTERNAL_TABLE 5 /* row group frame, row frame, cell frame, ... */
-
- /**
- * Bit-flag that indicates whether the element is replaced. Applies to inline,
- * block-level, floating, and absolutely positioned elements
- */
- #define NS_CSS_FRAME_TYPE_REPLACED 0x8000
-
- /**
- * Helper macros for telling whether items are replaced
- */
- #define NS_FRAME_IS_REPLACED(_ft) \
- (NS_CSS_FRAME_TYPE_REPLACED == ((_ft) & NS_CSS_FRAME_TYPE_REPLACED))
-
- #define NS_FRAME_REPLACED(_ft) \
- (NS_CSS_FRAME_TYPE_REPLACED | (_ft))
-
- /**
- * A macro to extract the type. Masks off the 'replaced' bit-flag
- */
- #define NS_FRAME_GET_TYPE(_ft) \
- ((_ft) & ~NS_CSS_FRAME_TYPE_REPLACED)
-
- #define NS_INTRINSICSIZE NS_UNCONSTRAINEDSIZE
- #define NS_SHRINKWRAPWIDTH NS_UNCONSTRAINEDSIZE
- #define NS_AUTOHEIGHT NS_UNCONSTRAINEDSIZE
- #define NS_AUTOMARGIN NS_UNCONSTRAINEDSIZE
- #define NS_AUTOOFFSET NS_UNCONSTRAINEDSIZE
- // NOTE: there are assumptions all over that these have the same value, namely NS_UNCONSTRAINEDSIZE
- // if any are changed to be a value other than NS_UNCONSTRAINEDSIZE
- // at least update AdjustComputedHeight/Width and test ad nauseum
-
- /**
- * Reflow state passed to a frame during reflow.
- *
- * @see nsIFrame#Reflow()
- */
- struct nsHTMLReflowState {
- // the reflow states are linked together. this is the pointer to the
- // parent's reflow state
- const nsHTMLReflowState* parentReflowState;
-
- // the frame being reflowed
- nsIFrame* frame;
-
- // the reason for the reflow
- nsReflowReason reason;
-
- // the incremental reflow path, when the reflow reason is
- // eReflowReason_Incremental. Specifically, this corresponds to the
- // portion of the incremental reflow path from `frame' down. Note
- // that it is safe to assume that this is non-null: we maintain the
- // invariant that it contains a valid nsReflowPath pointer when
- // reason == eReflowReason_Incremental.
- nsReflowPath *path;
-
- // the available width in which to reflow the frame. The space
- // represents the amount of room for the frame's border, padding,
- // and content area (not the margin area. The parent frame deals
- // with the child frame's margins). The frame size you choose should
- // fit within the available width.
- nscoord availableWidth;
-
- // A value of NS_UNCONSTRAINEDSIZE for the available height means
- // you can choose whatever size you want. In galley mode the
- // available height is always NS_UNCONSTRAINEDSIZE, and only page
- // mode involves a constrained height. The element's the top border
- // and padding, and content, must fit. If the element is complete
- // after reflow then its bottom border, padding and margin (and
- // similar for its complete ancestors) will need to fit in this
- // height.
- nscoord availableHeight;
-
- // rendering context to use for measurement
- nsIRenderingContext* rendContext;
-
- // The type of frame, from css's perspective. This value is
- // initialized by the Init method below.
- nsCSSFrameType mFrameType;
-
- // pointer to the space manager associated with this area
- nsSpaceManager* mSpaceManager;
-
- // LineLayout object (only for inline reflow; set to NULL otherwise)
- nsLineLayout* mLineLayout;
-
- // The appropriate reflow state for the containing block (for
- // percentage widths, etc.) of this reflow state's frame.
- const nsHTMLReflowState *mCBReflowState;
-
- // The computed width specifies the frame's content area width, and it does
- // not apply to inline non-replaced elements
- //
- // For replaced inline frames, a value of NS_INTRINSICSIZE means you should
- // use your intrinsic width as the computed width
- //
- // For block-level frames, the computed width is based on the width of the
- // containing block, the margin/border/padding areas, and the min/max width.
- // A value of NS_SHRINKWRAPWIDTH means that you should choose a width based
- // on your content. The width may be as large as the specified maximum width
- // (see mComputedMaxWidth).
- nscoord mComputedWidth;
-
- // The computed height specifies the frame's content height, and it does
- // not apply to inline non-replaced elements
- //
- // For replaced inline frames, a value of NS_INTRINSICSIZE means you should
- // use your intrinsic height as the computed height
- //
- // For non-replaced block-level frames in the flow and floated, a value of
- // NS_AUTOHEIGHT means you choose a height to shrink wrap around the normal
- // flow child frames. The height must be within the limit of the min/max
- // height if there is such a limit
- //
- // For replaced block-level frames, a value of NS_INTRINSICSIZE
- // means you use your intrinsic height as the computed height
- nscoord mComputedHeight;
-
- // Computed margin values
- nsMargin mComputedMargin;
-
- // Cached copy of the border values
- nsMargin mComputedBorderPadding;
-
- // Computed padding values
- nsMargin mComputedPadding;
-
- // Computed values for 'left/top/right/bottom' offsets. Only applies to
- // 'positioned' elements
- nsMargin mComputedOffsets;
-
- // Computed values for 'min-width/max-width' and 'min-height/max-height'
- nscoord mComputedMinWidth, mComputedMaxWidth;
- nscoord mComputedMinHeight, mComputedMaxHeight;
-
- // Compact margin available space
- nscoord mCompactMarginWidth;
-
- // Cached pointers to the various style structs used during intialization
- const nsStyleDisplay* mStyleDisplay;
- const nsStyleVisibility* mStyleVisibility;
- const nsStylePosition* mStylePosition;
- const nsStyleBorder* mStyleBorder;
- const nsStyleMargin* mStyleMargin;
- const nsStylePadding* mStylePadding;
- const nsStyleText* mStyleText;
-
- // a frame (e.g. nsTableCellFrame) which may need to generate a special
- // reflow for percent height calculations
- nsIPercentHeightObserver* mPercentHeightObserver;
-
- // a frame (e.g. nsTableFrame) which initiates a special reflow for percent height calculations
- nsIFrame* mPercentHeightReflowInitiator;
-
- // CSS margin collapsing sometimes requires us to reflow
- // optimistically assuming that margins collapse to see if clearance
- // is required. When we discover that clearance is required, we
- // store the frame in which clearance was discovered to the location
- // requested here.
- nsIFrame** mDiscoveredClearance;
-
- // This value keeps track of how deeply nested a given reflow state
- // is from the top of the frame tree.
- PRInt16 mReflowDepth;
-
- struct ReflowStateFlags {
- PRUint16 mSpecialHeightReflow:1; // used by tables to communicate special reflow (in process) to handle
- // percent height frames inside cells which may not have computed heights
- PRUint16 mNextInFlowUntouched:1; // nothing in the frame's next-in-flow (or its descendants)
- // is changing
- PRUint16 mIsTopOfPage:1; // is the current context at the top of a page?
- PRUint16 mBlinks:1; // Keep track of text-decoration: blink
- PRUint16 mVisualBidiFormControl:1; // Keep track of descendants of form controls on Visual Bidi pages
- PRUint16 mHasClearance:1; // Block has clearance
- PRUint16 mAssumingHScrollbar:1; // parent frame is an nsIScrollableFrame and it
- // is assuming a horizontal scrollbar
- PRUint16 mAssumingVScrollbar:1; // parent frame is an nsIScrollableFrame and it
- // is assuming a vertical scrollbar
- } mFlags;
-
- #ifdef IBMBIDI
- nscoord mRightEdge;
- #endif
-
- #ifdef DEBUG
- // hook for attaching debug info (e.g. tables may attach a timer during reflow)
- void* mDebugHook;
-
- static const char* ReasonToString(nsReflowReason aReason);
- #endif
-
- // Note: The copy constructor is written by the compiler automatically. You
- // can use that and then override specific values if you want, or you can
- // call Init as desired...
-
- // Initialize a <b>root</b> reflow state with a rendering context to
- // use for measuring things.
- nsHTMLReflowState(nsPresContext* aPresContext,
- nsIFrame* aFrame,
- nsReflowReason aReason,
- nsIRenderingContext* aRenderingContext,
- const nsSize& aAvailableSpace);
-
- // Initialize a <b>root</b> reflow state for an <b>incremental</b>
- // reflow.
- nsHTMLReflowState(nsPresContext* aPresContext,
- nsIFrame* aFrame,
- nsReflowPath* aReflowPath,
- nsIRenderingContext* aRenderingContext,
- const nsSize& aAvailableSpace);
-
- // Initialize a reflow state for a child frames reflow. Some state
- // is copied from the parent reflow state; the remaining state is
- // computed.
- nsHTMLReflowState(nsPresContext* aPresContext,
- const nsHTMLReflowState& aParentReflowState,
- nsIFrame* aFrame,
- const nsSize& aAvailableSpace,
- nsReflowReason aReason,
- PRBool aInit = PR_TRUE);
-
- // Same as the previous except that the reason is taken from the
- // parent's reflow state.
- nsHTMLReflowState(nsPresContext* aPresContext,
- const nsHTMLReflowState& aParentReflowState,
- nsIFrame* aFrame,
- const nsSize& aAvailableSpace);
-
- // Used when you want to override the default containing block
- // width and height. Used by absolute positioning code
- nsHTMLReflowState(nsPresContext* aPresContext,
- const nsHTMLReflowState& aParentReflowState,
- nsIFrame* aFrame,
- const nsSize& aAvailableSpace,
- nscoord aContainingBlockWidth,
- nscoord aContainingBlockHeight,
- nsReflowReason aReason);
-
- // This method initializes various data members. It is automatically
- // called by the various constructors
- void Init(nsPresContext* aPresContext,
- nscoord aContainingBlockWidth = -1,
- nscoord aContainingBlockHeight = -1,
- nsMargin* aBorder = nsnull,
- nsMargin* aPadding = nsnull);
- /**
- * Find the content width of the containing block of aReflowState
- */
- static nscoord
- GetContainingBlockContentWidth(const nsHTMLReflowState* aReflowState);
-
- /**
- * Adjust content MEW take into account the settings of the CSS
- * 'width', 'min-width' and 'max-width' properties.
- */
- nscoord AdjustIntrinsicMinContentWidthForStyle(nscoord aWidth) const;
- /**
- * Adjust content maximum-width take into account the settings of
- * the CSS 'width', 'min-width' and 'max-width' properties.
- */
- nscoord AdjustIntrinsicContentWidthForStyle(nscoord aWidth) const;
-
- /**
- * Find the containing block of aFrame. This may return null if
- * there isn't one (but that should really only happen for root
- * frames).
- */
- static nsIFrame* GetContainingBlockFor(const nsIFrame* aFrame);
-
- /**
- * Get the page box reflow state, starting from a frames
- * <B>parent</B> reflow state (the parent reflow state may or may not end
- * up being the containing block reflow state)
- */
- static const nsHTMLReflowState*
- GetPageBoxReflowState(const nsHTMLReflowState* aParentRS);
-
- /**
- * Compute the border plus padding for <TT>aFrame</TT>. If a
- * percentage needs to be computed it will be computed by finding
- * the containing block, use GetContainingBlockReflowState.
- * aParentReflowState is aFrame's
- * parent's reflow state. The resulting computed border plus padding
- * is returned in aResult.
- */
- static void ComputeBorderPaddingFor(nsIFrame* aFrame,
- const nsHTMLReflowState* aParentRS,
- nsMargin& aResult);
-
- /**
- * Calculate the raw line-height property for the given frame. The return
- * value, if line-height was applied and is valid will be >= 0. Otherwise,
- * the return value will be <0 which is illegal (CSS2 spec: section 10.8.1).
- */
- static nscoord CalcLineHeight(nsPresContext* aPresContext,
- nsIRenderingContext* aRenderingContext,
- nsIFrame* aFrame);
-
- void InitFrameType();
-
- void ComputeContainingBlockRectangle(nsPresContext* aPresContext,
- const nsHTMLReflowState* aContainingBlockRS,
- nscoord& aContainingBlockWidth,
- nscoord& aContainingBlockHeight);
-
- void CalculateBlockSideMargins(nscoord aAvailWidth,
- nscoord aComputedWidth);
-
- /**
- * Apply the mComputed(Min/Max)(Width/Height) values to the content
- * size computed so far. If a passed-in pointer is null, we skip
- * adjusting that dimension.
- */
- void ApplyMinMaxConstraints(nscoord* aContentWidth, nscoord* aContentHeight) const;
-
- protected:
-
- void InitCBReflowState();
-
- void InitConstraints(nsPresContext* aPresContext,
- nscoord aContainingBlockWidth,
- nscoord aContainingBlockHeight,
- nsMargin* aBorder,
- nsMargin* aPadding);
-
- void CalculateHypotheticalBox(nsPresContext* aPresContext,
- nsIFrame* aPlaceholderFrame,
- nsIFrame* aBlockFrame,
- nsMargin& aBlockContentArea,
- const nsHTMLReflowState* cbrs,
- nsHypotheticalBox& aHypotheticalBox);
-
- void InitAbsoluteConstraints(nsPresContext* aPresContext,
- const nsHTMLReflowState* cbrs,
- nscoord aContainingBlockWidth,
- nscoord aContainingBlockHeight);
-
- void ComputeRelativeOffsets(const nsHTMLReflowState* cbrs,
- nscoord aContainingBlockWidth,
- nscoord aContainingBlockHeight);
-
- void ComputeBlockBoxData(nsPresContext* aPresContext,
- const nsHTMLReflowState* cbrs,
- nsStyleUnit aWidthUnit,
- nsStyleUnit aHeightUnit,
- nscoord aContainingBlockWidth,
- nscoord aContainingBlockHeight);
-
- void ComputeHorizontalValue(nscoord aContainingBlockWidth,
- nsStyleUnit aUnit,
- const nsStyleCoord& aCoord,
- nscoord& aResult);
-
- void ComputeVerticalValue(nscoord aContainingBlockHeight,
- nsStyleUnit aUnit,
- const nsStyleCoord& aCoord,
- nscoord& aResult);
-
- // Computes margin values from the specified margin style information, and
- // fills in the mComputedMargin member
- void ComputeMargin(nscoord aContainingBlockWidth,
- const nsHTMLReflowState* aContainingBlockRS);
-
- // Computes padding values from the specified padding style information, and
- // fills in the mComputedPadding member
- void ComputePadding(nscoord aContainingBlockWidth,
- const nsHTMLReflowState* aContainingBlockRS);
-
- // Calculates the computed values for the 'min-Width', 'max-Width',
- // 'min-Height', and 'max-Height' properties, and stores them in the assorted
- // data members
- void ComputeMinMaxValues(nscoord aContainingBlockWidth,
- nscoord aContainingBlockHeight,
- const nsHTMLReflowState* aContainingBlockRS);
-
- nscoord CalculateHorizBorderPaddingMargin(nscoord aContainingBlockWidth);
-
- // Adjust Computed sizes for Min/Max Width and box-Sizing (if
- // aAdjustForBoxSizing is true)
- // - guarantees that the computed height/width will be non-negative
- // If the value goes negative (because the padding or border is greater than
- // the width/height and it is removed due to box sizing) then it is driven to 0
- void AdjustComputedHeight(PRBool aAdjustForBoxSizing);
- void AdjustComputedWidth(PRBool aAdjustForBoxSizing);
-
- #ifdef IBMBIDI
- /**
- * Test whether the frame is a form control in a visual Bidi page.
- * This is necessary for backwards-compatibility, because most visual
- * pages use logical order for form controls so that they will
- * display correctly on native widgets in OSs with Bidi support
- * @param aPresContext the pres context
- * @return whether the frame is a BIDI form control
- */
- PRBool IsBidiFormControl(nsPresContext* aPresContext);
- #endif
- };
-
- #endif /* nsHTMLReflowState_h___ */
-
-