gecko-dev/layout/generic/nsInlineFrame.h

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/* rendering object for CSS display:inline objects */

#ifndef nsInlineFrame_h___
#define nsInlineFrame_h___

#include "nsHTMLContainerFrame.h"
#include "nsAbsoluteContainingBlock.h"
#include "nsLineLayout.h"

class nsAnonymousBlockFrame;

#define NS_INLINE_FRAME_CID \
 { 0x88b298af, 0x8b0e, 0x4592,{0x9e, 0xc6, 0xea, 0x4c, 0x4b, 0x3f, 0xf7, 0xa4}}

#define nsInlineFrameSuper nsHTMLContainerFrame

// NS_INLINE_FRAME_HARD_TEXT_OFFSETS is used for access keys, where what
// would normally be 1 text frame is split into 3 sets of an inline parent 
// and text child (the pre access key text, the underlined key text, and
// the post access key text). The offsets of the 3 text frame children
// are set in nsCSSFrameConstructor

#define NS_INLINE_FRAME_HARD_TEXT_OFFSETS            0x00100000

/**  In Bidi left (or right) margin/padding/border should be applied to left
 *  (or right) most frame (or a continuation frame).
 *  This state value shows if this frame is left (or right) most continuation
 *  or not.
 */
#define NS_INLINE_FRAME_BIDI_VISUAL_STATE_IS_SET     0x00200000

#define NS_INLINE_FRAME_BIDI_VISUAL_IS_LEFT_MOST     0x00400000

#define NS_INLINE_FRAME_BIDI_VISUAL_IS_RIGHT_MOST    0x00800000

/**
 * Inline frame class.
 *
 * This class manages a list of child frames that are inline frames. Working with
 * nsLineLayout, the class will reflow and place inline frames on a line.
 */
class nsInlineFrame : public nsInlineFrameSuper
{
public:
  friend nsIFrame* NS_NewInlineFrame(nsIPresShell* aPresShell, nsStyleContext* aContext);

  // nsISupports overrides
  NS_IMETHOD QueryInterface(const nsIID& aIID, void** aInstancePtr);

  // nsIFrame overrides
  NS_IMETHOD BuildDisplayList(nsDisplayListBuilder*   aBuilder,
                              const nsRect&           aDirtyRect,
                              const nsDisplayListSet& aLists);

  virtual void Destroy();

#ifdef ACCESSIBILITY
  NS_IMETHODIMP GetAccessible(nsIAccessible** aAccessible);
#endif

#ifdef DEBUG
  NS_IMETHOD GetFrameName(nsAString& aResult) const;
#endif
  virtual nsIAtom* GetType() const;

  virtual PRBool IsFrameOfType(PRUint32 aFlags) const
  {
    return nsInlineFrameSuper::IsFrameOfType(aFlags &
      ~(nsIFrame::eBidiInlineContainer));
  }

  virtual PRBool IsEmpty();
  virtual PRBool IsSelfEmpty();

  virtual PRBool PeekOffsetCharacter(PRBool aForward, PRInt32* aOffset);
  
  // nsIHTMLReflow overrides
  virtual void AddInlineMinWidth(nsIRenderingContext *aRenderingContext,
                                 InlineMinWidthData *aData);
  virtual void AddInlinePrefWidth(nsIRenderingContext *aRenderingContext,
                                  InlinePrefWidthData *aData);
  virtual nsSize ComputeSize(nsIRenderingContext *aRenderingContext,
                             nsSize aCBSize, nscoord aAvailableWidth,
                             nsSize aMargin, nsSize aBorder, nsSize aPadding,
                             PRBool aShrinkWrap);
  NS_IMETHOD Reflow(nsPresContext* aPresContext,
                    nsHTMLReflowMetrics& aDesiredSize,
                    const nsHTMLReflowState& aReflowState,
                    nsReflowStatus& aStatus);

  virtual PRBool CanContinueTextRun() const;

  // Take all of the frames away from this frame. The caller is
  // presumed to keep them alive.
  void StealAllFrames() {
    mFrames.SetFrames(nsnull);
  }

  /**
   * Return true if the frame is leftmost frame or continuation.
   */
  PRBool IsLeftMost() const {
    // If the frame's bidi visual state is set, return is-leftmost state
    // else return true if it's the first continuation.
    return (GetStateBits() & NS_INLINE_FRAME_BIDI_VISUAL_STATE_IS_SET)
             ? (GetStateBits() & NS_INLINE_FRAME_BIDI_VISUAL_IS_LEFT_MOST)
             : (!GetPrevInFlow());
  }

  /**
   * Return true if the frame is rightmost frame or continuation.
   */
  PRBool IsRightMost() const {
    // If the frame's bidi visual state is set, return is-rightmost state
    // else return true if it's the last continuation.
    return (GetStateBits() & NS_INLINE_FRAME_BIDI_VISUAL_STATE_IS_SET)
             ? (GetStateBits() & NS_INLINE_FRAME_BIDI_VISUAL_IS_RIGHT_MOST)
             : (!GetNextInFlow());
  }

protected:
  // Additional reflow state used during our reflow methods
  struct InlineReflowState {
    nsIFrame* mPrevFrame;
    nsInlineFrame* mNextInFlow;
    PRPackedBool mSetParentPointer;  // when reflowing child frame first set its
                                     // parent frame pointer

    InlineReflowState()  {
      mPrevFrame = nsnull;
      mNextInFlow = nsnull;
      mSetParentPointer = PR_FALSE;
    };
  };

  nsInlineFrame(nsStyleContext* aContext) : nsInlineFrameSuper(aContext) {}

  virtual PRIntn GetSkipSides() const;

  nsresult ReflowFrames(nsPresContext* aPresContext,
                        const nsHTMLReflowState& aReflowState,
                        InlineReflowState& rs,
                        nsHTMLReflowMetrics& aMetrics,
                        nsReflowStatus& aStatus);

  nsresult ReflowInlineFrame(nsPresContext* aPresContext,
                             const nsHTMLReflowState& aReflowState,
                             InlineReflowState& rs,
                             nsIFrame* aFrame,
                             nsReflowStatus& aStatus);

  virtual nsIFrame* PullOneFrame(nsPresContext* aPresContext,
                                 InlineReflowState& rs,
                                 PRBool* aIsComplete);

  virtual void PushFrames(nsPresContext* aPresContext,
                          nsIFrame* aFromChild,
                          nsIFrame* aPrevSibling);

};

//----------------------------------------------------------------------

/**
 * Variation on inline-frame used to manage lines for line layout in
 * special situations (:first-line style in particular).
 */
class nsFirstLineFrame : public nsInlineFrame {
public:
  friend nsIFrame* NS_NewFirstLineFrame(nsIPresShell* aPresShell, nsStyleContext* aContext);

#ifdef DEBUG
  NS_IMETHOD GetFrameName(nsAString& aResult) const;
#endif
  virtual nsIAtom* GetType() const;
  NS_IMETHOD Reflow(nsPresContext* aPresContext,
                    nsHTMLReflowMetrics& aDesiredSize,
                    const nsHTMLReflowState& aReflowState,
                    nsReflowStatus& aStatus);

  // Take frames starting at aFrame until the end of the frame-list
  // away from this frame. The caller is presumed to keep them alive.
  void StealFramesFrom(nsIFrame* aFrame);

protected:
  nsFirstLineFrame(nsStyleContext* aContext) : nsInlineFrame(aContext) {}

  virtual nsIFrame* PullOneFrame(nsPresContext* aPresContext,
                                 InlineReflowState& rs,
                                 PRBool* aIsComplete);
};

//----------------------------------------------------------------------

// Derived class created for relatively positioned inline-level elements
// that acts as a containing block for child absolutely positioned
// elements

class nsPositionedInlineFrame : public nsInlineFrame
{
public:
  nsPositionedInlineFrame(nsStyleContext* aContext) : nsInlineFrame(aContext) {}

  virtual ~nsPositionedInlineFrame() { } // useful for debugging

  virtual void Destroy();

  NS_IMETHOD SetInitialChildList(nsIAtom*        aListName,
                                 nsIFrame*       aChildList);
  NS_IMETHOD AppendFrames(nsIAtom*        aListName,
                          nsIFrame*       aFrameList);
  NS_IMETHOD InsertFrames(nsIAtom*        aListName,
                          nsIFrame*       aPrevFrame,
                          nsIFrame*       aFrameList);
  NS_IMETHOD RemoveFrame(nsIAtom*        aListName,
                         nsIFrame*       aOldFrame);

  NS_IMETHOD BuildDisplayList(nsDisplayListBuilder*   aBuilder,
                              const nsRect&           aDirtyRect,
                              const nsDisplayListSet& aLists);

  virtual nsIAtom* GetAdditionalChildListName(PRInt32 aIndex) const;

  virtual nsIFrame* GetFirstChild(nsIAtom* aListName) const;

  NS_IMETHOD Reflow(nsPresContext*          aPresContext,
                    nsHTMLReflowMetrics&     aDesiredSize,
                    const nsHTMLReflowState& aReflowState,
                    nsReflowStatus&          aStatus);
  
  virtual nsIAtom* GetType() const;

protected:
  nsAbsoluteContainingBlock mAbsoluteContainer;
};

#endif /* nsInlineFrame_h___ */