layout/base/nsStyleChangeList.h

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  37
  38 /*
  39  * a list of the recomputation that needs to be done in response to a
  40  * style change
  41  */
  42
  43 #ifndef nsStyleChangeList_h___
  44 #define nsStyleChangeList_h___
  45
  46 #include "nsError.h"
  47 #include "nsChangeHint.h"
  48
  49 class nsIFrame;
  50 class nsIContent;
  51
  52 // XXX would all platforms support putting this inside the list?
  53 struct nsStyleChangeData {
  54   nsIFrame*   mFrame;
  55   nsIContent* mContent;
  56   nsChangeHint mHint;
  57 };
  58
  59 static const PRUint32 kStyleChangeBufferSize = 10;
  60
  61 // Note:  nsStyleChangeList owns a reference to
  62 //  nsIContent pointers in its list.
  63 class nsStyleChangeList {
  64 public:
  65   nsStyleChangeList();
  66   ~nsStyleChangeList();
  67
  68   PRInt32 Count(void) const {
  69     return mCount;
  70   }
  71
  72   /**
  73    * Fills in pointers without reference counting.
  74    */
  75   nsresult ChangeAt(PRInt32 aIndex, nsIFrame*& aFrame, nsIContent*& aContent,
  76                     nsChangeHint& aHint) const;
  77
  78   /**
  79    * Fills in a pointer to the list entry storage (no reference counting
  80    * involved).
  81    */
  82   nsresult ChangeAt(PRInt32 aIndex, const nsStyleChangeData** aChangeData) const;
  83
  84   nsresult AppendChange(nsIFrame* aFrame, nsIContent* aContent, nsChangeHint aHint);
  85
  86   void Clear(void);
  87
  88 protected:
  89   nsStyleChangeList&  operator=(const nsStyleChangeList& aCopy);
  90   PRBool              operator==(const nsStyleChangeList& aOther) const;
  91
  92   nsStyleChangeData*  mArray;
  93   PRInt32             mArraySize;
  94   PRInt32             mCount;
  95   nsStyleChangeData   mBuffer[kStyleChangeBufferSize];
  96
  97 private:
  98   nsStyleChangeList(const nsStyleChangeList&); // not implemented
  99 };
 100
 101
 102 #endif /* nsStyleChangeList_h___ */